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Chinese Journal of Aeronautics 2023年第5期36卷 33-40页

作者： Jörg SCHLÜter Dan ZHAO Abhishek SARKAR School of Engineering Deakin UniversityWaurn Ponds 3216Australia College of Engineering University of CanterburyChristchurch 8041New Zealand School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore

A better understanding of the mixing behavior of excited turbulent mixing layers is critical to a number of aerospace *** studies of excited turbulent mixing layers focused on single frequency excitation or the excitation with fundamental and its second harmonic *** is a lack of detailed studies on applying low and higher frequency *** this study,we have performed large-eddy simulations of periodically excited turbulent mixing *** excitation consists of a fundamental frequency and its third *** have used phase-averaging to identify the vortex structure and strength in the mixing layer,and we have studied the vortex *** different vortex paring mechanisms are observed depending on the phase shift between the two excitation *** influence of these two mechanisms on the mixing of a passive scalar is also *** is found that exciting the mixing layer with these low and high frequencies has initially an adverse influence on the mixing process;however,it improves the mixing further downstream of the splitter plate with the excitation using a phase shift ofΔφ=πshowing the best mixing *** present works shed lights on the fundamental vortex dynamics,and has great potential for aeronautical,automotive and combustion engineering applications.

关键词： Flow control Flow excitation Large eddy simulations Turbulent mixing layer Vortex dynamics

Smooth free-cycle dynamic soaring in unspecified shear wind via quadratic programming

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Chinese Journal of Aeronautics 2022年第7期35卷 19-29页

作者： Haichao HONG Benedikt GRüter Patrick PIPREK Florian HOLZAPFEL Institute of Flight System Dynamics Technical University of MunichGarching D-85748Germany

Harvesting wind energy is promising for extending long-endurance flights,which can be greatly facilitated by a flight technique called dynamic *** presented study is concerned with generating model-based trajectories with smooth control histories for dynamic soaring maneuvers exploiting wind *** desired smoothness is achieved by introducing a trigonometric series parameterization for the controls,which are formulated with respect to the normalized ***,the periodicity of the trigonometric functions is leveraged to facilitate the connection of cycles and streamline the problem *** relying on a specified wind profile,a freefinal-time quadratic programming-based control strategy is developed for the online correction of the flight trajectory,which requires only the instant wind *** and online numerical studies show the trade-off to achieve the smoothness and demonstrate the effectiveness of the proposed method in a varying wind field.

关键词： Dynamic soaring Optimal control Quadratic programming Trajectory generation Trigonometric series

Revealing the topological phase diagram of ZrTe_(5) using the complex strain fields of microbubbles

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npj Computational Materials 2022年第1期8卷 1685-1691页

作者： Zoltán Tajkov Dániel Nagy Konrád Kandrai János Koltai LászlóOroszlány Péter Süle Zsolt EHorváth Péter Vancsó Levente Tapasztó Péter Nemes-Incze Centre for Energy Research Institute of Technical Physics and Materials Science1121BudapestHungary Department of Physics of Complex Systems ELTE Eötvös Loránd University1117BudapestHungary ELTE Eötvös Loránd University Department of Biological Physics1117BudapestHungary Budapest University of Technology and Economics 1111BudapestHungary

Topological materials host robust properties,unaffected by microscopic perturbations,owing to the global topological properties of the bulk electron *** in which the topological invariant can be changed by easily tuning external parameters are especially sought *** pentatelluride(ZrTe_(5))is one of a few experimentally available materials that reside close to the boundary of a topological phase transition,allowing the switching of its invariant by mechanical ***,we unambiguously identify a topological insulator–metal transition as a function of strain,by a combination of ab initio calculations and direct measurements of the local charge *** model quantitatively describes the response to complex strain patterns found in bubbles of few layer ZrTe_(5) without fitting parameters,reproducing the mechanical deformation-dependent closing of the band gap observed using scanning tunneling *** calculate the topological phase diagram of ZrTe_(5) and identify the phase at equilibrium,enabling the design of device architectures,which exploit the topological switching characteristics of the system.

关键词： density topological invariant

WEALTHy KOANS AROUND 200 BC IN THE CONTEXT OF HELLENISTIC SOCIAL HISTORy

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Journal of Ancient Civilizations 2021年第2期36卷 235-267,300,301页

作者： Péter Kató Eötvös Loránd University Budapest

This paper aims to evaluate the data relating to the Koan elite around 200 BC,in the light of general trends of the post-Classical polis’s social *** article first presents prosopographical information regarding the top contributors of the famous wartime subscription list(IG XII 4,1,75–77),their relatives,as well as other contributors with more modest amounts of money who can nevertheless be identified as rich,influential,and prominent members of the local *** paper demonstrates the existence of an influential elite which exercised its power mostly outside the framework of political offices(archai),through religious activities and priesthoods,patronage in associations,and interstate ***,the paper identifies those factors that limited the influence of the elite:the instability of these families,the sustainment of democratic political institutions,and the tendency to emphasize communal efforts over individual benefactions–what is attested primarily by the specific Koan epigraphic habit.

关键词： outside elite religious

Macrophage’s little helper: vitamin A directs alternatively activated monocyte-derived macrophages to tissue-resident macrophages

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Cellular & Molecular Immunology 2017年第10期14卷 805-808页

作者： Dirk Schlüter Florian H Heidel Institute of Medical Microbiology and Hospital Hygiene Otto-von-Guericke University MagdeburgMagdeburg 39120Germany Organ-Specific Immune Regulation Helmholtz-Center for Infection ResearchBraunschweig 38124Germany Innere Medizin II Hämatologie und OnkologieUniversitätsklinikum JenaJena 07745Germany Leibniz-Institute on Aging Fritz-Lipmann-InstituteJenaGermany

Tissue-resident macrophages originate from the yolk sac in a Myb-independent manner and populate all organs during *** macrophages are a heterogeneous self-renewing population that adapt to the organ-specific local environment to contribute to tissue *** on the age,organ and inflammatory conditions,macrophages that are derived from hematopoietic stem cells(HSCs)in a Myb-dependent manner may also infiltrate organs and develop into tissueresident macrophages.

关键词： organs vitamin homeostasis

Hardy spaces on Lie groups of polynomial growth

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Science China Mathematics 2010年第1期53卷 23-40页

作者： ter ELST A F M ROBINSON Derek W Department of Mathematics University of Auckland Center for Mathematics and its Applications Mathematical Science Institute

We give several characterizations of Hardy spaces associated with complex, second-order,subelliptic operators on Lie groups with polynomial growth.

关键词： Lie groups Hardy spaces heat kernel

Subject Area Risk Assessment of Four Hungarian Universities with a View to the QS University Rankings by Subject

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Journal of Data and Information Science 2022年第4期7卷 61-80页

作者： Péter Sasvári Anna Urbanovics Public Governance and International Studies University of Public ServiceHungary University of Miskolc Hungary

Purpose:The aim of our paper is to investigate the role of a mentor leading a research team in the overall scientific performance of an academic institution and the possible risks of their departure with a special attention to their publication ***/methodology/approach:By using SciVal subject area data,we composed a formula describing the level of vulnerability of any given university in the case of losing any of its leading mentors,identifying other risk factors by dividing their careers into separate ***:It turns out that the higher field-weighed citation impact is,the better position universities reach in the rankings by subject and the vulnerability of institutions highly depends on the mentors,especially in view of their contribution to the topic *** limitations:The analysis covers the publication output of leading researchers working at four Hungarian universities,the scope of the analysis is worth being *** implications:Our analysis has the potential to give an applicable systemic approach as well as a data collection scheme to university managements so as to formulate an inclusive and comprehensive research strategy involving the introduction of a reward system aimed at publications and further encouraging national and international research ***/value:The methodology and the principles of risk assessment laid down in our paper are not restricted to measuring the vulnerability level of a limited group of academic institutions,they can be appropriately used for investigating the role of mentors or leading researchers at every university across the globe.

关键词： QS Rankings by Subject Scientific Competitiveness Risk Analysis Subject Area Exposure

Variations of optic properties of water under action of static magnetic field

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Chinese Science Bulletin 2007年第23期52卷 3179-3182页

作者： DENG Bo pang XiaoFeng School of Life Science and Technology University of Electronic Science and Technology of China Chengdu 610054 China

Effects of static magnetic field on optic properties of water are investigated by infrared spectroscopy, ultraviolet spectroscopy and X-ray diffraction, respectively. The ultraviolet spectroscopy experiments show the changes of properties of water under action of static magnetic field, in the region of 191 to 400 nm. The infrared experiment shows that the water exposed in a magnetic field had saturation and memory effects. The magnetized effects increased with increasing exposed time, but were weakened with increasing of time when the magnetic field was removed. In the X-ray experiment, the strength of diffraction increased also, after the water was exposed in magnetic field. Meanwhile, the shift of peak and increase of strength of X-ray diffraction of magnetized water added with nanoFe3O4 occurred as compared with that of pure water added with nano Fe3O4. This result suggests that the magnetized wa- ter has certain magnetism. Finally, these phenomena are simply explained by the molecular structure of water and the theory of magnetization of water.

关键词：红外线光谱学紫外线光谱学 X衍射静力学磁铁

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安大略省猪肉协会简介

国外畜牧学（猪与禽） 2024年第5期44卷 28-28页

作者： Vincent ter Beek 不详

安大略省猪肉协会是将安大略省所有的养猪生产者聚集在一起的组织。据2023年统计显示,安大略省有1919家猪场,共饲养了580万头猪。该省的生猪产量约占加拿大的四分之一,仅次于魁北克省,是加拿大第二大生猪生产地。大多数猪场位于安大略... 详细信息

安大略省猪肉协会是将安大略省所有的养猪生产者聚集在一起的组织。据2023年统计显示,安大略省有1919家猪场,共饲养了580万头猪。该省的生猪产量约占加拿大的四分之一,仅次于魁北克省,是加拿大第二大生猪生产地。大多数猪场位于安大略省西南部。

关键词：生猪生产养猪生产者安大略省魁北克省加拿大猪肉猪场协会

Influence of the Boreal Summer Intraseasonal Oscillation on Extreme Temperature Events in the Northern Hemisphere

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Journal of Meteorological Research 2018年第4期32卷 534-547页

作者： yifei DIAO Tim LI pang-Chi HSU Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environmental ChangeCollaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science &Technology International Pacific Research Center and Department of Atmospheric Sciences School of Ocean and Earth Science and Technology University of Hawaii

The impact of the boreal summer intraseasonal oscillation （BSISO） on extreme hot and cool events was investig-ated, by analyzing the observed and reanalysis data for the period from 1983 to 2012. It is found that the frequency of the extreme events in middle and high latitudes is significantly modulated by the BSISO convection in the tropics, with a 3-9-day lag. During phases 1 and 2 when the BSISO positive rainfall anomaly is primarily located over a northwest-southeast oriented belt extending from India to Maritime Continent and a negative rainfall anomaly ap- pears in western North Pacific, the frequency of extreme hot events is 40% more than the frequency of non-extreme hot events. Most noticeable increase appears in midlatitude North Pacific （north of 40°N） and higher-latitude polar region. Two physical mechanisms are primarily responsible for the change of the extreme frequency. First, an upper-tropo-spheric Rossby wave train （due to the wave energy propagation） is generated in response to a negative heating anom-aly over tropical western North Pacific in phases 1 and 2. This wave train consists of a strong high pressure anomaly center northeast of Japan, a weak low pressure anomaly center over Alaska, and a strong high pressure anomaly cen-ter over the western coast of United States. Easterly anomalies to the south of the two strong midlatitude high pres-sure centers weaken the climatological subtropical jet along 40°N, which is accompanied by anomalous subsidence and warming in North Pacific north of 40°N. Second, an enhanced monsoonal heating over South Asia and East Asia sets up a transverse monsoonal overturning circulation, with large-scale ascending （descending） anomalies over trop-ical Indian （Pacific） Ocean. Both the processes favor more frequent extreme hot events in higher-latitude Northern Hemisphere. An anomalous atmospheric general circulation model is used to confirm the tropical heating effect.

关键词： boreal summer intraseasonal oscillation extreme hot events extreme cool events Rossby wave train monsoonal circulation