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international Journal of Digital Earth 2017年第1期10卷 103-120页

作者： Sergio Trilles Òscar Belmonte Sven Schade Joaquìn Huerta institute.of New Imaging Technologies Universitat Jaume ICastellóde la PlanaSpain European Commission–Joint research Centre Institute for Environment and SustainabilityIspraItaly

Pushed by the Internet of Things(IoT)paradigm modern sensor networks monitor a wide range of phenomena,in areas such as environmental monitoring,health care,industrial processes,and smart *** networks provide a continuous pulse of the almost infinite activities that are happening in the physical space and are thus,key enablers for a Digital Earth Nervous ***,the rapid processing of these sensor data streams still continues to challenge traditional data-handling solutions and new approaches are being *** propose a generic answer to this challenge,which has the potential to support any form of distributed real-time *** neutral methodology follows a brokering approach to work with different kinds of data sources and uses web-based standards to achieve *** a proof of concept,we implemented the methodology to detect anomalies in real-time and applied it to the area of environmental *** developed system is capable of detecting anomalies,generating notifications,and displaying the recent situation to the user.

关键词： Big data real-time analysis data streams sensor networks interoperability brokering approach

Liftoff of a New Hovering Oscillating-wing Micro Aerial Vehicle

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Journal of Bionic Engineering 2021年第3期18卷 649-661页

作者： Xiangcong Zhou Deyuan Zhang Zhiyong Huang Xiaogang Song Hao Liu Lin Feng institute.of Bionic and Micro-Nano Systems School of Mechanical Engineering and AutomationBeihang UniversityBeijing 100191China Beijing Advanced Innovation Center for Biomedical Engineering Beihang UniversityBeijing 100191China Graduate School of Engineerings Chiba University Chiba 263-8522Japan Shanghai Jiao Tong University and Chiba University international Cooperative research Center Shanghai 200240China

Hovering ability forms the basis for space operations of Micro Aerial Vehicles(MAVs).The problem of uneven load puts high demands on the wing *** this paper,a new hovering-mode for MAVs,inspired by flapping flight in bees and hummingbirds but using high-aspect-ratio and low-stress wings,is *** from the flapping actuations that occur at the wing roots,the two wings are driven back and forth in a straight *** simplify the design and control the angle of attack,passive wing rotation is *** numerical results and analysis show that the maximum stress of the oscillating wing is approximately 1/6 of that of the flapping wing when the lift of the oscillating wing is twice that of the flapping wing.A theoretical aerodynamic model of the kinematics of the vehicle's driving mechanism was developed to fulfill its *** measurements indicate that the vehicle generates a sufficiently high cycle-averaged vertical thrust(71 g)for liftoff at a maximum frequency of 5.56 Hz,thereby validating the proposed aerodynamic ***,liftoff performance is presented to visually demonstrate the vertical take-off capabilities and hovering potential of the aeromechanical solution.

关键词： bioinspired oscillating-wing high aspect ratio low-stress wings micro aerial vehicles vertical take-off and hovering

Assimilation of Satellite Altimetry into a Western North Pacific Operational Model

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Advances in Atmospheric Sciences 2001年第5期18卷 767-786页

作者： Masafumi Kamachi, Tsurane Kuragano, Noriya Yoshioka, Jiang Zhu, and Francesco Uboldi Meteorological research institute. 1-1 Nagamine, Tsukubo 305-0052 Japan Japan Meteorological Agenry, 1-3-4 Otemachi, Tokyo 100-8122 Japan institute.of Atmospheric Physics Meteorological research institute.Tsukuba Japan Japan Meteorological Agency Tokyo Japan institute.of Atmospheric Physics Chinese Academy of Science Beijing China Magritte SNC Milano Italy

An ocean data assimilation system, COMPASS-K (the Comprehensive Ocean Modeling, Prediction, Analysis and Synthesis System in the Kuroshio-region), has been developed at the Meteorological research institute.(MRI). The purposes of the development are understanding ocean variability in the Kuroshio region as a local response to a global climate change with assimilated four-dimensional data sets, development of an operational system in the Japan Meteorological Agency, and for the GODAE (Global Ocean Data Assimilation Experiment) project. The model is an eddy permitting version of an MRI-OGCM. Space-time decorrelation scales of ocean variability are estimated with TOPEX / POSEIDON (T/P) altimeter data. Subsurface temperature and salinity fields are projected from the T / P altimeter data with a statistical correlation method and are assimilated into the model with a time-retrospective nudging scheme. Seasonal variation in the western North Pacific is investigated. Realistic space-time distribution of the physical quantities, the path of Kuroshio and its separation from Honshu are captured well. The Kuroshio volume transport is well reproduced in a reanalysis experiment of 1993. Preliminary predictability experiments are done in February and March, 1994. Predictability diagram shows the time scale of the predictability for temperature field is about 17 days in the Kuroshio south of Japan. This time scale is smaller than that in the North Atlantic.

关键词： assimilation Kuroshio predictability

Effect of Ni/(La+Mg) Ratio on Structure and Electrochemical Performance of La-Mg-Ni Alloy System

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Journal of Iron and Steel research international 2009年第3期16卷 83-88页

作者： DONG Xiao-ping YANG Li-ying ZHANG Yang-huan WANG Xin-lin College of Quality and Technical Supervision Hebei University Baoding 071002 Hebei China Department ofFunctional Material research China Iron and Steel Research Institute Group Beijing 100081 China

As the alloy with the most suitable Ni/（La＋Mg） ratio has higher capacity and good cycle stability,the effects of Ni/（La＋Mg） ratios on the electrochemical performances of the La0.80Mg0.20Nix （x=3.5 to 5.0） alloys have been investigated to find the most suitable Ni/（La＋Mg） ratio. The results of XRD and SEM observations show that the phase composition of the alloys varies with different Ni/（La＋Mg） ratios. When Ni/（La＋Mg） is not more than 4.25,all the alloys contain LaNi5 and （La,Mg）2Ni7 phases,in addition,the LaMg and （La,Mg）Ni3 phases exist in the x=3.5 and 3.75 alloys,respectively. The LaMg2Ni9 phase exists in the x=4.25 alloy. There are the LaNi5 and LaMg2Ni9 phases in the x=4.5,4.75,and 5.0 alloys. The phase abundance and cell volume change with different Ni content. When the Ni/（La＋Mg） ratio is not more than 4.25,the alloys possess excellent activation capability,however,the activation capabilities of the alloys decrease with a further increase in the Ni/（La＋Mg） ratio. With increasing the Ni/（La＋Mg） ratio,the maximum discharge capacities,the medium voltages,and the cycle stabilities of the alloys first increase and then decrease. When the Ni/（La＋Mg） ratio is 3.75,the corresponding alloy has the maximum discharge capacity among all the alloys. However,the cycle stability of the Ni/（La＋Mg）=4.0 alloy is better than that of the others.

关键词： Ni/(La+Mg) ratio La-Mg-Ni alloy system structure characteristic electrochemical performance

Analysis of Wind Power Assessment Based on the WRF Model

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Atmospheric and Oceanic Science Letters 2014年第2期7卷 126-131页

作者： LI Ji-Hang GUO Zhen-Hai WANG Hui-Jun LI Ji-Hang WANG Hui-Jun Nansen-Zhu international research Centre (NZC) Institute of Atmospheric Physics the Chinese Academy of Sciences Beijing 100029 China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China University of the Chinese Academy of Sciences Beijing 100049 China

Assessing wind energy is a key step in selecting a site for a wind farm. The accuracy of the assessment is essential for the future operation of the wind farm. There are two main methods for assessing wind power: one is based on observational data and the other relies on mesoscale numerical weather prediction(NWP). In this study, the wind power of the Liaoning coastal wind farm was evaluated using observations from an anemometer tower and simulations by the Weather research and Forecasting(WRF) model, to see whether the WRF model can produce a valid assessment of the wind power and whether the downscaling process can provide a better evaluation. The paper presents long-term wind data analysis in terms of annual, seasonal, and diurnal variations at the wind farm, which is located on the east coast of Liaoning Province. The results showed that, in spring and summer, the wind speed, wind direction, wind power density, and other main indicators were consistent between the two methods. However, the values of these parameters from the WRF model were significantly higher than the observations from the anemometer tower. Therefore, the causes of the differences between the two methods were further analyzed. There was much more deviation in the original material, National Centers for Environmental Prediction(NCEP) final(FNL) Operational Global Analysis data, in autumn and winter than in spring and summer. As the region is vulnerable to cold-air outbreaks and windy weather in autumn and winter, and the model usually forecasted stronger high or low systems with a longer duration, the predicted wind speed from the WRF model was too large.

关键词： wind power assessment anemometer tower data WRF model variance analysis

Strategies for the construction of supramolecular assemblies from poly-NHC ligand precursors

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Science China Chemistry 2021年第5期64卷 701-718页

作者： Yang Li Jian-Gang Yu Li-Li Ma Man Li Yuan-Yuan An Ying-Feng Han Key Laboratory of Synthetic and Natural Functional Molecule Chemistry FM&EM International Joint LaboratoryCollege of Chemistry and Materials ScienceNorthwest UniversityXi’an 710127China College of Chemical and Material Engineering Quzhou UniversityQuzhou 324000China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

The field of supramolecular assemblies has developed rapidly in the last few decades,thanks in a large part to their diverse *** assemblies have been mostly based on Werner-type coordination motifs in which metal centres are coordinated by nitrogen or oxygen ***,N-heterocyclic carbene(NHC)ligands have been employed as carbon donors not only because of their appealing structures but also due to the extensive applications in catalysis,biomedicine and material science of the resulting *** the last decade,NHC-based supramolecular assemblies have witnessed rapid growth and extensive application in molecular recognition,luminescent materials and *** different topological systems,a diverse selection of poly-NHC precursors and synthetic strategies is crucial to precisely control the synthesis of supramolecular *** synthetic strategies have been developed to synthesise two-dimensional(2D)molecular metallacycles and three-dimensional(3D)metallacages from a wide range of poly-NHC precursors,including a straightforward one-pot strategy,supramolecular transmetalation,stepwise synthesis,an improved one-pot strategy involving self-sorting behaviour of 3D metallacages and a subtle variation strategy of poly-NHC ligand *** review offers a summary of the synthetic strategies applied for the construction of different poly-NHC-based supramolecular assemblies,particularly emphasizes recent progress in the synthesis of large and complex supramolecular assemblies from poly-NHC precursors,and further attention is given to their application in postsynthetic modifications(PSMs),host-guest chemistry,luminescent properties and biomedical applications.

关键词： N-heterocyclic carbene organometallic chemistry supramolecular chemistry synthetic strategies applications

Preoperative application of combination of portal venous injection of donor spleen cells and intraperitoneal injection of rapamycin prolongs the survival of cardiac allografts in mice

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Asian Pacific Journal of Tropical Medicine 2017年第5期10卷 433-439页

作者： Wen-lin Gong Chuang Sha Gang Du Zhong-gui Shan Zhong-quan Qi Su-fang Zhou Nuo Yang Yong-xiang Zhao National Center for international research of Biological Targeting Diagnosis and Therapy Guangxi Key Laboratory of Biological Targeting Diagnosis and Therapy ResearchCollaborative Innovation Center for Targeting Tumor Diagnosis and TherapyGuangxi Medical University Department of Cardiac Surgery Zhongshan HospitalXiamen University Organ Transplantation institute Xiamen University Department of Cardio-Thoracic Surgery The First Affiliated Hospital of Guang Xi Medical University

Objective:To investigate the effects of preoperative portal venous injection of donor spleen cells(PVIDSC) and intraperitoneal injection of rapamycin in the acute rejection of cardiac allograft in mice and the underlying mechanisms. Methods:Homogenous female B6 mice and BALB/c mice were used as recipients and donors of heart transplantation. These mice were randomly divided into different groups and received PVIDSC alone,rapamycin alone,or PVIDSC and rapamycin combined therapy. In addition,the underlying mechanism was studied by measuring a number of cytokines. Results:Preoperative combination of PVIDSC and intraperitoneal injection of rapamycin significantly prolonged the survival of heterotopic cardiac allograft in mice,but had no effects on the survival time of cardiac allografts in mice pre-sensitized by skin grafting. Preoperative combination of PVIDSC and intraperitoneal injection of rapamycin increased the expression of IL-10 and Foxp3 and reduced the expression of INF-γ. Short-term preoperative administration of rapamycin promotes the expression of CD4^+CD25^+Foxp3^+ regulator T cells. However,preoperative using alone of rapamycin,or combination of PVIDSC and rapamycin had no effects on the inhibition of proliferation of memory T cells. Conclusions:Preoperative application of combination of PVIDSC and rapamycin significantly prolonged the survival time of cardiac allografts in mice but not in mice pre-sensitized by skin grafting. This may be explained by the fact that combination of PVIDSC and rapamycin inhibited the cellular immune response and induced the expression of IL-10 from Tr1 cells and CD4^+CD25^+FoxP3^+ regulatory T cells.

关键词： Heart transplantation tolerance Portal venous injection of donor spleen cells Rapamycin

Corrosion and passive behaviour of duplex stainless steel 2205 at different cooling rates in a simulated marine-environment solution

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Journal of Iron and Steel research international 2018年第9期25卷 943-953页

作者： Shang-lin Lv Zhong-min Yang Bin Zhang Jie Chen Ying Chen Xiao-bin Li National Construction Steel Quality Supervision and Test Centre Central Research Institute of Building and Construction Co. Ltd. Beijing 100088 China Department of Structural Steels Central Iron and Steel Research Institute Beijing 100081 China China University of Pertroleum-Beijing Beijing 102249China

The corrosion and passive behaviour of duplex stainless steel 2205 at six cooling rates （1, 5, 10, 15, 20 ℃ s^-1 and water quenched） in a simulated marine-environment solution was investigated using electrochemical measurements of potentiostatic critical pitting temperature, potentiodynamic polarisation curves, electrochemical impedance spectroscopy and Mott-Schottky curves. The microstructural evolution and pitting morphologies of the specimens were visualised using an optical microscope and scanning electron microscope. The electrochemical responses of the passive film show that passivity of the steel was enhanced as the cooling rate increased; however, the threshold cooling rate was 20 ℃ s^-1, beyond which pitting corrosion resistance remained stable. Based on the analyses of microstructural evolution and pit morphologies, the proportion of the ferrite phase increased with the cooling rate and the ratio of austenite and ferrite was close to 1：1. The pitting size decreased as the cooling rate increased, and most metastable pits on specimens were located in the ferrite phase and on the ferrite-austenite interface. Thus, pitting resistance of steel is governed by the phase that provides the lowest pitting resistance equivalent number. The optimised pitting corrosion resistance for steel 2205 was achieved when it was greater than or equal to 20℃ s^-1.

关键词： Duplex stainless steel Cooling rate Pitting corrosion Passive film Electrochemistry

Slags containing transition metal(chromium and vanadium)oxides——Conversion from ticking bombs to valuable resources:Collaborative studies between KTH and USTB

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international Journal of Minerals,Metallurgy and Materials 2022年第4期29卷 750-757页

作者： Seshadri Seetharaman Lijun Wang Haijuan Wang Royal institute.of Technology(KTH) Stockholm 10044Sweden Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

As the steel industry expands worldwide,slag dumps with transition metals(especially chromium and vanadium)are becoming more common,posing a serious environmental *** the properties of slags containing transition metal oxides,as well as how to use the slags to recover and recycle metal values,is *** this end,the University of Science and Technology Beijing(USTB)and Royal institute.of Technology(KTH)have been collaborating on slags containing transition metals for *** research was carried out from a fundamental viewpoint to get a better understanding of the structure of these slags and their properties,as well as industrial *** research focused on the three“R”s,***,recovery,and *** present paper attempts to highlight some of the important achievements in these joint studies.

关键词： transition metals vanadium chromium recovery collaborative study

ANURBS-Enhanced Finite Volume Method for Steady Euler Equations with Goal-Oriented h-Adaptivity

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Communications in Computational Physics 2022年第7期32卷 490-523页

作者： Xucheng Meng Guanghui Hu research Center for Mathematics Beijing Normal UniversityZhuhai 519087China BNU-HKBU United international College Zhuhai 519087China Department of Mathematics University of MacaoMacao SARChina ZhuhaiUMScience and Technology research institute ZhuhaiGuangdong ProvinceChina Guangdong-Hong Kong-Macao Joint Laboratory for Data-Driven Fluid Dynamics and Engineering Applications University of MacaoMacao SARChina

In[A NURBS-enhanced finite volume solver for steady Euler equations,***,***,***.,Vol.359,pp.77–92],aNURBS-enhanced finite volume method was developed to solve the steady Euler equations,in which the desired high order numerical accuracy was obtained for the equations imposed in the domain with a curved *** this paper,the method is significantly improved in the following ways:(i)a simple and efficient point inversion technique is designed to compute the parameter values of points lying on a NURBS curve,(ii)with this new point inversion technique,the h-adaptive NURBS-enhanced finite volume method is introduced for the steady Euler equations in a complex domain,and(iii)a goal-oriented a posteriori error indicator is designed to further improve the efficiency of the algorithm towards accurately calculating a given quantity of *** results obtained from a variety of numerical experiments with different flow configurations successfully show the effectiveness and robustness of the proposed method.

关键词： Steady Euler equations NURBS-enhanced finite volume method goal-oriented a posteriori error estimation non-oscillatory k-exact reconstruction point inversion