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Positive Solutions for a Class of Fractional p-Laplacian Equation with Critical Sobolev Exponent and Decaying Potentials

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Acta Mathematicae Applicatae Sinica 2022年第2期38卷 463-483页

作者： na LI Xiao-ming HE College of Science Minzu University of ChinaBeijing 100081China

In this paper,we study the existence of positive solution for the p-Laplacian equations with frac-tional critical nonlinearity{-Δ)_(p)^(s)u+V(x)|u|^(p-2)u=K(x)f(u)+P(x)|u|p_(s)^(*)-^(2)u,x∈R^(N),u∈Ds,p(RN),where s∈(0,1),p_(s)^(*)=Np/N-sp,N>sp,p>1 and V(x),K(x)are positive continuous functions which vanish at infinity,f is a function with a subcritical growth,and P(x)is bounded,nonnegative continuous *** using variational method in the weighted spaces,we prove the above problem has at least one positive solution.

关键词： Fractional p-Laplacian Variational methods Mountain Pass Theorem Critical growth Vanishing potential

Enhancing the efectiveness of film cooling

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航空动力学报 2007年第4期22卷 531-539页

作者： Tom I-P Shih Sangkwon na Department of Aerospace Engineering Iowa State University Ames Iowa 50011 U. S. A

Advanced gas turbine stages are designed to operate at increasingly higher inlet temperatures to increase thermal efficiency and specific power *** maintain durability and reasonable life,film cooling is needed in addition to internal cooling,especially for the first *** cooling lowers material temperature by forced convection inside film-cooling holes and by forming a layer of coolant about component surfaces to insulate them from the hot ***,each cooling jet forms a pair of counter-rotating vortices that entrains hot gas and causes the film-cooling jet to lift off from the surface that it is intended to *** paper gives an overview of efforts to enhance the effectiveness of *** paper also describes two new design *** design concept seeks to minimize the entrainment of hot gases underneath of film-cooling jets by using flow-aligned *** other design concept shifts the interaction between the approaching hot gas and the cooling jet to occur further above the surface by using an upstream *** both design concepts,computational fluid dynamics results are presented to examine their usefulness in enhancing film-cooling effectivenes

关键词：航空动力推进系统薄雾冷却冷却效率燃气轮机流体动力学

DESIGN EFFICIENCY FoR MINIMuM PRoJECTIoN uNIFoRMITY DESIGNS WITH TWo LEVELS

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Journal of Systems Science & Complexity 2011年第4期24卷 761-768页

作者： Hong QIN na Z0u Shangli ZHANG Department of Statistics Central China Normal University Wuhan 430079 China. Department of Mathematics Beijing Jiaotong University Beijing 100044 China.

The objective of this paper is to study the issue of design efficiency for minimum projection uniformity designs. The results show that for orthogonal arrays with strength two, the minimum projection uniformity criter... 详细信息

关键词： Generalized minimum aberration minimum projection uniformity orthogonal array uniform design.

Role of N/Z in Pre-scission Neutrons as an observable of Nuclear Friction

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Communications in Theoretical Physics 2009年第8期52卷 329-332页

作者： CHEN na YE Wei School of Applied Mathematics Nanjing University of Finance and Economics Nanjing 210046 China Department of Physics Southeast University Nanjing 210096 China

A dynamical Langevin model is employed to evaluate the excess of the neutron emission in the fission ofheavy nuclei ^(240)Cf,^(246)Cf,^(254)Cf,^(240)u relative to the standard statistical-model prediction at various saddle-to-scissionfriction *** is shown that when the neutron-to-proton ratio N/Z of the system increases,the sensitivityof the excess to the friction decreases substantially,and it almost disappears for ^(240)*** suggest that using thosecompound systems with low N/Z favors an accurate determination for the saddle-to-scission friction strength based onthe measurement of the pre-scission neutron multiplicity.

关键词： pre-scission neutron multiplicity N/Z effect nuclear friction Langevin model

基于无监督深度领域对抗适配的在线剩余寿命预测方法

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郑州大学学报（理学版） 2025年第1期57卷 81-87页

作者：刘可盈张艳娜毛文涛王纳河南师范大学计算机与信息工程学院河南新乡453007 智慧商务与物联网技术河南省工程实验室河南新乡453007

为解决未知工况下旋转设备在线剩余寿命(remaining useful life,RuL)预测时计算代价大和误差累积问题,提出一种基于无监督深度领域对抗适配的在线RuL预测方法。首先,利用离线退化数据和在线早期故障数据,构建深度领域对抗网络作为预训... 详细信息

为解决未知工况下旋转设备在线剩余寿命(remaining useful life,RuL)预测时计算代价大和误差累积问题,提出一种基于无监督深度领域对抗适配的在线RuL预测方法。首先,利用离线退化数据和在线早期故障数据,构建深度领域对抗网络作为预训练模型。其次,将在线贯序数据块输入预训练模型的回归预测器中重新领域适配,得到在线伪标签。最后,将预训练模型的结构和参数迁移到目标域模型,冻结目标域模型的部分参数,并利用在线数据块和伪标签对目标域模型剩余参数进行微调,实现在线数据的RuL动态预测。在IEEE PHM Challenge 2012轴承数据集上进行实验,结果表明,所提方法可以贯序、准确地预测在线轴承RuL值,为在线场景下的轴承RuL预测提供了一种实用化的解决方案。

关键词：剩余寿命预测迁移学习领域适配无监督学习在线学习

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Discordant patterns of genetic variation between mitochondrial and microsatellite markers in Acanthogobius ommaturus across the coastal areas of China

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Acta oceanologica Sinica 2023年第4期42卷 72-80页

作者： Chenyu Song Zhong Tu na Song Key Laboratory of Mariculture(ocean university of China) Ministry of EducationQingdao 266003China Shandong Fisheries Development and Resources Conservation Center Yantai 264003China

Acanthogobius ommaturus, which belongs to the family Gobiidae, is a euryhaline and demersal fish that is widely distributed in the coastal areas, harbors, and estuaries of China, D. P. R. Korea and Japan. In this study, the genetic diversity and genetic structure of five geographical populations of A. ommaturus was assessed using the mitochondrial hypervariable region gene and microsatellite markers. The results of the two genetic markers indicated that the A. ommaturus populations had a high level of genetic diversity. The mitochondrial marker detected weak genetic differentiation among populations, and the Neighbor-Joining tree showed that there was no obvious pedigree branches and geographic structure as well. However, population of Zhoushan showed significant genetic differentiation with other populations by microsatellite markers. The population of *** has not experienced bottleneck effect recently. We speculated that the Pleistocene climate change and juvenile fish dispersal played an important role in the population differentiation of A. ommaturus.

关键词： mitochondrial markers microsatellite markers genetic diversity genetic structure Acanthogobius ommaturus

Facile Construction of Carbon Dots Layer and oxygen Vacancies Simultaneously onto Ti0_(2) to Enhance Photoreduction Activity

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Chinese Journal of Chemistry 2021年第5期39卷 1310-1318页

作者： Jingyu Zhao Yarn Li Ping na School of Chemical Engineering and Technology Tianjin UniversityTianjin 300354China

We reported a facile and green hydrothermal strategy to tailor the carbon dots layer(CDL)and oxygen vacancies(Vo)modified on Ti0_(2),by using ascorbic acid as CDL precursor and Vo *** amorphous CDL was uniformly coated on the surface of the as prepared CDL@Tio_(2-x) composites by Ti-o-C *** the increase of carbon content,the amorphous CDL gradually became thicker,while the Vo concentration first increased and then decreased.1.5 CDL@Tio_(2-x) possessed the highest Vo *** the decoration of CDL and Vo,the photoreduction properties of CDL@Tio_(2-x) composites were significantly *** simulated solar light and visible light,the reaction rates of 1.5 CDL@Tio_(2-x) were 9.6 times and 216 times higher than that of pure Ti0_(2)/***,the results discovered that CDL and Vo influenced the properties of CDL@Tio_(2-x) composites in different *** primary function of CDL was to improve the utilization of solar light,and the enhancement of the charge transfer ability was decided by Vo and CDL *** work provides a new strategy for the modification of Ti0_(2) and sheds new light on the respective role of CDL and Vo when they coexist in the catalyst.

关键词： Carbon oxygen vacancies Titanium dioxide Photocatalysis Chromium

Land use change and its driving factors in the ecological function area:A case study in the Hedong Region of the Gansu Province,China

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Journal of Arid Land 2024年第1期16卷 71-90页

作者： WEI Zhudeng Du na Yu Wenzheng School of Geographical Science Nanjing University of Information Science&TechnologyNanjing 210044China

Land use and cover change(LuCC)is important for the provision of ecosystem *** increasing number of recent studies link LuCC processes to ecosystem services and human well-being at different scales ***,the dynamic of land use and its drivers receive insufficient attention within ecological function areas,particularly in quantifying the dynamic roles of climate change and human activities on land use based on a long time *** study utilizes geospatial analysis and geographical detectors to examine the temporal dynamics of land use patterns and their underlying drivers in the Hedong Region of the Gansu Province from 1990 to *** indicated that grassland,cropland,and forestland collectively accounted for approximately 99% of the total land *** initially increased and then decreased after 2000,while grassland decreased with *** contrast,forestland and construction land were continuously expanded,with net growth areas of 6235.2 and 455.9 km^(2),*** 1990 to 2020,cropland was converted to grassland,and both of them were converted to forestland as a *** expansion of construction land primarily originated from *** 2000 to 2005,land use experienced intensified temporal dynamics and a shift of relatively active zones from the central to the southeastern *** yield,economic factors,and precipitation were the major factors accounting for most land use *** impacts on land use changes were stronger before 1995,succeeded by the impact of animal husbandry during 1995-2000,followed by the impacts of grain production and gross domestic product(GDP)after ***,agricultural and pastoral activities,coupled with climate change,exhibited stronger enhancement effects after 2000 through their interaction with population and economic *** patterns closely correlated with ecological restoration projects in China since *** study implies the importance of synergy be

关键词： land use land type geographic detector driving mechanism Hedong Region

String and Ball-Like Tio_2/rGo Composites with High Photo-catalysis Degradation Capability for Methylene Blue

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Transactions of Tianjin university 2018年第3期24卷 272-281页

作者： Fengyun Xu Ping na School of Chemical Engineering and Technology Tianjin University

Novelthree-dimensionalstring and ball-like titanium dioxide/reduced graphene oxide, Tio_2/rGo(STG) composites were prepared using a one-step hydrolysis process followed by a low-temperature hydrothermaltreatment. The STG composites exhibited excellent photo-catalytic degradation performance for methylene blue owing to a good synergistic effect between Tio_2 and rGo. The STG composites with 1.0 wt% of rGo loading exhibited the highest removalrate of 86.0% for methylene blue and its reaction rate constant(5.27 × 10^(-3) min^(-1)) was much higher than those of pure string and ball-like Tio_2(ST). In addition, the STG composites also showed an outstanding capability for the photo-catalysis degradation of other cationic dyes. In addition, a possible photo-catalytic degradation mechanism for the STG composite was postulated, in which~?o_2^- and~·oH were the main oxidizing groups. This work of fers new insights into a better design and preparation of novelcomposite materials for the removalof organic dyes.

关键词： String and ball-like Tio2 Reduced graphene oxide Synergistic effect Photo-catalytic Methylene blue