检索结果-南通市图书馆

Dynamic stall control over an airfoil by NS-DBD actuation

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2020年第10期29卷 370-379页

作者： He-Sen Yang Guang-yin Zhao hua liang Biao Wei Science and Technology on Plasma Dynamics Laboratory Air Force Engineering UniversityXi'an 710038China State Key Laboratory of Aerodynamics China Aerodynamics Research and Development CenterMianyang 621000China

The wind tunnel test was conducted with an NACA 0012 airfoil to explore the flow control effects on airfoil dynamic stall by NS-DBD plasma actuation. Firstly, light and deep dynamic stall states were set, based on the static stall characteristics of airfoil at a Reynolds number of 5.8 × 105. Then, the flow control effect of NS-DBD on dynamic stall was studied and the influence law of three typical reduced frequencies (k = 0.05, k = 0.05, and k = 0.15) was examined at various dimensionless actuation frequencies (F+ = 1, F+ = 2, and F+ = 3). For both light and deep dynamic stall states, NS-DBD had almost no effect on upstroke. However, the lift coefficients on downstroke were increased significantly and the flow control effect at F+ = 1 is the best. The flow control effect of the light stall state is more obvious than that of deep stall state under the same actuation conditions. For the same stall state, with the reduced frequency increasing, the control effect became worse. Based on the in being principles of flow separation control by NS-DBD, the mechanism of dynamic stall control was discussed and the influence of reduced frequency on the dynamic flow control was analyzed. Different from the static airfoil flow separation control, the separated angle of leading-edge shear layer for the airfoil in dynamic stall state is larger and flow control with dynamic oscillation is more difficult. The separated angle is closely related to the effective angle of attack, so the effect of dynamic stall control is greatly dependent on the history of angles of attack.

关键词： flow control dynamic stall dielectric barrier discharge(DBD) nanosecond pulse reduced frequency

Josephson Current in f-Wave Superconductor/f-Wave Superconductor Junctions

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2009年第10期52卷 715-720页

作者： LIAO Yan-hua DONG Zheng-Chao liang Zhi-Peng yin Zai-Feng School of Mathematics and Physics Huangshi Institute of Technology Huangshi 435100 China School of Science Nantong University Nantong 226000 China Department of Physics Suzhou University Suzhou 215006 China Department of Physics College of Science Yanbian University Yanji 133002 China

We study the temperature T and the phase of the Josephson critical current I（Ф） by taking into account the roughness scattering effect at inerface in an f-wave superconductor （S）/Insulator layer （I）/f-wave superconductor （S） junction. It is found that the Josephson critical currents in f-wave Sir-wave S, the barrier strength and the roughness strength at inerface always suppress the Andreev reflection. When α=β, the phase dependence of the Josephson current I（Ф） between two f-wave S is predicted to be sin Ф; particularly, when a α≠ β, the phase dependence of the Josephson current I（Ф） between two f-wave superconductors is not predicted to be sin Ф and with the barrier strength increasing, the period of the I（Ф） turns decrease.

关键词： f-wave S/f-wave S junction f-wave superconductor (f S) Josephson current

血清尿酸水平与帕金森病不同运动亚型之间的关系

在线全文

学校读者我要写书评

暂无评论

蚌埠医学院学报 2017年第7期42卷 852-853,857页

作者：张丽娜屈洪党陈育华殷亮李倩倩蚌埠医学院第一附属医院神经内科安徽蚌埠233004

目的:探讨血清尿酸(UA)水平与帕金森病(PD)不同运动亚型及临床分期之间的关系。方法:入选PD病人(PD组)及年龄、性别相匹配的健康对照组(HC组)各50例,PD病人根据运动障碍症状分为震颤为主型(TD组)和姿势异常及步态障碍为主型(PIGD组);病... 详细信息

目的:探讨血清尿酸(UA)水平与帕金森病(PD)不同运动亚型及临床分期之间的关系。方法:入选PD病人(PD组)及年龄、性别相匹配的健康对照组(HC组)各50例,PD病人根据运动障碍症状分为震颤为主型(TD组)和姿势异常及步态障碍为主型(PIGD组);病情严重程度采用Hoehn-Yahr(H-Y)分级评定为早期(H-Y0.05)。结论:UA水平的变化可能参与了PD不同运动亚型的发病机制,并可能成为预测PD发病风险、判断病情严重程度及运动分型的生物学标志物。

关键词：帕金森病尿酸运动亚型

On a Problem of Potentially Pancyclic-graphic Sequences Due to S.B. Rao

在线全文

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2019年第2期35卷 465-474页

作者： Jian-hua yin Department of Mathematics College of Information Science and TechnologyHainan University

A non-increasing sequenceπ=(d_1,d_2,···,d_n)of nonnegative integers is said to be potentially hamiltonian-graphic(*** pancyclic-graphic)if it is realizable by a simple graph on n vertices containing a hamiltonian cycle(*** cycles of every length from 3 to n).*** and ***(*** Ser.B,13(1972),185–191)and Kundu(Discrete Math.,6(1973),367–376)presented a characterization ofπ=(d_1,d_2,···,d_n)that is potentially ***(Lecture Notes in Math.,No.855,Springer Verlag,1981,417–440,Unsolved Problem 2)further posed the following problem:present a characterization ofπ=(d_1,d_2,···,d_n)that is potentially *** this paper,we first give solution to this problem for the case of 4≤n≤***,we also show that a near regular graphic sequenceπ=(d_1,d_2,···,d_n)with dn≥3 is potentially pancyclic-graphic.

关键词： graphic sequence potentially hamiltonian-graphic sequence potentially pancyclic-graphic sequence

A Rao-type Characterization for a Sequence to Have a Realization Containing an Arbitrary Subgraph H

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2014年第3期30卷 389-394页

作者： Jian hua yin Department of Mathematics College of Information Science and TechnologyHainan University

Let G be an arbitrary spanning subgraph of the complete graph Kr＋1 on r＋1 vertices and Kr＋1-E（G） be the graph obtained from Kr＋1 by deleting all edges of G.A non-increasing sequence π=（d1,d2,...,dn） of nonnegative integers is said to be potentially Kr＋1-E（G）-graphic if there is a graph on n vertices that has π as its degree sequence and contains Kr＋1-E（G） as a *** this paper,a characterization of π that is potentially Kr＋1-E（G）-graphic is given,which is analogous to the Erdo s–Gallai characterization of graphic sequences using a system of *** is a solution to an open problem due to Lai and *** a corollary,a characterization of π that is potentially Ks,tgraphic can also be obtained,where Ks,t is the complete bipartite graph with partite sets of size s and *** is a solution to an open problem due to Li and yin.

关键词： Degree sequence potentially Kr+1--E(G)-graphic sequence potentially Ks,t-graphicsequence

Cycloaddition reactions of benzyne with olefins

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2014年第12期25卷 1535-1539页

作者： Zhao Chen Xie Han Jin-hua liang Jun yin Guang-Ao Yu Sheng-hua Liu Key Laboratory of Pesticide and Chemical Biology Ministry of EducationCollege of ChemistryCentral China Normal University

Some novel cycloaddition reactions based on benzyne and olefins have been *** reactions were performed in the absence of a transition metal catalyst,and they displayed good *** cycloaddition reactions of benzyne with olefins provide effective routes for synthesizing benzocyclobutenes,biaryl compounds and 9,10-dihydrophenanthrene derivatives.

关键词： Cycloaddition Benzyne Olefins Benzocyclobutenes Biaryl 9 10-Dihydrophenanthrene

Reactive oxygen species and nitric oxide scavenging nanoparticles alleviating rheumatoid arthritis through adjusting the seeds and growing soils

在线全文

学校读者我要写书评

暂无评论

Acta Pharmaceutica Sinica B 2023年第12期13卷 5016-5029页

作者： Peng hua Ruifeng liang Yanbei Tu Yuying yin Man-Kay Law Meiwan Chen State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoMacao SARChina State Key Laboratory of Analog and Mixed-Signal VLSI IME and FST-ECEUniversity of MacaoMacao SARChina

Normalizing inflamed soils including reactive oxygen species(ROS),nitric oxide(NO),cellfree DNA,and regulating infammation-related seeds such as macrophages,neutrophils,fibroblasts,represent a promising strategy to maintain synovial tissue homeostasis for rheumatoid arthritis(RA)***,ROS scavenging amphiphilic block copolymer PEGylated bilirubin and NO-scavenging PEGylated o-phenylenediamine were fabricated to self-assemble into a dually responsive nanoparticle loaded with JAK inhibitor notopterol(Not@BR/oPDA-PEG,NBOP NPs).The simultaneous ROS and NO depletion combined with JAK-STAT pathway inhibition could not only promote M2 polarization to reduce further ROS and NO generation,but also decrease cytokines and chemokines to prevent immune cell ***,NBOP NPs responded to high level ROS and NO,and disintegrated to release notopterol in inflamed joints as the hydrophobic heads BR and oPDA were transformed into hydrophilic *** released notopterol could inhibit the JAK-STAT pathway of infammatory cells to reduce the secretion of pro-inflammatory cytokines and *** strategy represented an effective way to regulate RA soils and seeds through breaking the positive feedback loop of inflammation aggravation,achieving an excellent anti-RA efficacy in a collagen-induced arthritis rat *** together,our work offered a reference to adjust RA soils and seeds for enhanced RA treatment.

关键词： Bilirubin o-Phenylenediamine Notopterol ROS and NO scavenging JAK-STATpathway Anti-inflammatory Cartilage protection Rheumatoid arthritis

Searching Activity Tra jectories with Semantics

在线全文

学校读者我要写书评

暂无评论

Journal of Computer Science & Technology 2019年第4期34卷 775-794页

作者： Li-hua yin Huiwen Liu Cyberspace Institute of Advanced Technology Guangzhou UniversityGuangzhou 510006China School of Information System Singapore Management UniversitySingapore 188065Singapore

With the widespread use of smart phones and mobile Internet,social network users have generated massive geo-tagged tweets,photos and videos to form lots of informative trajectories which reveal not only their spatio-temporal dynamics,but also their activities in the physical *** spatial trajectory query studies mainly focus on analyzing the spatio-temporal properties of the users'trajectories,while leaving the understanding of their activities largely *** this paper,we incorporate the semantics of the activity information embedded in trajectories into query modelling and processing,with the aim of providing end users more informative and meaningful *** this end,we propose a novel trajectory query that not only considers the spatio-temporal closeness but also,more importantly,leverages a proven technique in text mining field,probabilistic topic modelling,to capture the semantic relatedness of the activities between the data and *** support efficient query processing,we design a hierarchical grid-based index by integrating the probabilistic topic distribution on the substructures of trajectories and their spatio-temporal extent at the corresponding level of the index *** specialized structure enables a top-down search algorithm to traverse the index while pruning unqualified trajectories in spatial and topical dimensions *** experimental results on real-world datasets demonstrate the good efficiency and scalability performance of the proposed indices and trajectory search methods.

关键词： spatio-temporal database activity trajectory semantic understanding trajectory indexing trajectory query processing

Sliding-mode control for a rolling-missile with input constraints

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2020年第5期31卷 1041-1050页

作者： hua Siyu WANG Xugang ZHU yin The 802 Institute of Shanghai Academy of Space Flight Technology Shanghai 201100China School of Energy and Power Engineering Nanjing University of Science and TechnologyNanjing 210094China

This paper investigates the overload stabilization problem of the rolling-missile subject to parameters uncertainty and actuator saturation. In order to solve this problem, a sliding-mode control(SMC) scheme is technically employed by using the backstepping approach to make the dynamic system stable. In addition,SMC with the tanh-type switching function plays an important role in reducing intrinsic vibration. Furthermore, an auxiliary system(AS) is developed to compensate for nonlinear terms arising from input saturation. Finally, the simulation results provide a solution to demonstrate that the suggested SMC and the AS methodology have advantages of strong tracking capability, anti-interference ability and anti-saturation performance.

关键词： input constraint back-stepping approach sliding-mode control(SMC) auxiliary control system