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International Journal of Disaster Risk Science 2016年第3期7卷 245-256页

作者： hang Li Xiao-Bing hu Xiaomei Guo Zhen Xu P.h.A.J.M.van Gelder Academy of Disaster Reduction and Emergency Management Beijing Normal University State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Faculty of Technology Policy and Management Delft University of Technology School of Engineering University of Warwick

As an important infrastructure system, civil aviation network system can be severely affected by natural hazards. Although a natural hazard is usually local, its impact, through the network topology, can become *** by Wilkinson's work in 2012, this article proposes a new quantitative spatial vulnerability model for network systems, which emphasizes the spreading impact of spatially localized hazards on these systems. This model considers hazard location and area covered by a hazard,and spatially spreading impact of the hazard(including direct impact and indirect impact through network topology) and proposes an absolute spatial vulnerability index and a relative spatial vulnerability index to reflect the vulnerability of a network system to local hazards. The model is then applied to study the spatial vulnerability of the Chinese civil aviation network system. The simulation results show that(1) the proposed model is effective and useful to study spatial vulnerability of civil aviation network systems as the results well explain the general situation of the Chinese civil aviation system; and(2) the Chinese civil aviation network system is highly vulnerable to local hazards when indirect impacts through network connections are considered.

关键词： Civil aviation Network system Spatially localized hazards Vulnerability

The Lobster Eye Imager for Astronomy Onboard the SATech-01 Satellite

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Research in Astronomy and Astrophysics 2023年第9期23卷 66-78页

作者： Z.X.Ling X.J.Sun C.Zhang S.L.Sun G.Jin S.N.Zhang X.F.Zhang J.B.Chang F.S.Chen y.F.Chen Z.W.Cheng W.Fu y.X.han h.Li J.F.Li y.Li Z.D.Li P.R.Liu y.h.Lv X.h.Ma y.J.Tang C.B.Wang R.J.Xie y.L.Xue A.L.yan Q.Zhang C.y.Bao h.B.Cai h.Q.Cheng C.Z.Cui y.F.Dai D.W.Fan h.B.hu J.W.hu M.h.huang Z.Q.Jia C.C.Jin D.y.Li J.Q.Li h.y.Liu M.J.Liu y.Liu h.W.Pan y.L.Qiu M.Sugizaki h.Sun W.X.Wang y.L.Wang Q.y.Wu X.P.Xu y.F.Xu h.N.yang X.yang B.Zhang M.Zhang W.D.Zhang Z.Zhang D.h.Zhao X.Q.Cong B.W.Jiang L.h.Li X.B.Qiu J.N.Sun D.T.Su J.Wang C.Wu Z.Xu X.M.yang S.K.Zhang Z.Zhang N.Zhang y.F.Zhu h.y.Ban X.Z.Bi Z.M.Cai W.Chen X.Chen y.h.Chen y.Cui X.L.Duan Z.G Feng y.Gao J.W.he T.he J.J.huang F.Li J.S.Li T.J.Li T.T.Li h.Q.Liu L.Liu R.Liu S.Liu N.Meng Q.Shi A.T.Sun y.M.Wang y.B.Wang h.C.Wu D.X Xu y.Q yang y.yang X.S.yu K.X.Zhang y.L.Zhang y.h.Zhang y.T.Zhang h.Zhou X.C.Zhu J.S.Cheng L.Qin L.Wang Q.L.Wang M.Bai R.L.Gao Z.Ji y.R.Liu F.L.Ma y.J.Shi J.Su y.y.Tan J.Z.Tong h.T.Xu C.B.Xue G.F.Xue W.yuan National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Shanghai Institute of Technical Physics Chinese Academy of SciencesShanghai 200083China North Night Vision Technology Co. LTDNanjing 211106China Institute of high Energy Physics Chinese Academy of SciencesBeijing 100049China Science and Technology on Low-Light-Level Night Vision Laboratory Xi'an 710065China Innovation Academy for Microsatellites Chinese Academy of SciencesShanghai 201204China Institute of Electrical Engineering Chinese Academy of ScienceBeijing 100190China National Space Science Center Chinese Academy of ScienceBeijing 100190China

The Lobster Eye Imager for Astronomy(LEIA),a pathfinder of the Wide-field X-ray Telescope of the Einstein Probe mission,was successfully launched onboard the SATech-01 satellite of the Chinese Academy of Sciences on2022 July *** this paper,we introduce the design and on-ground test results of the LEIA *** stateof-the-art Micro-Pore Optics(MPO),a wide field of view of 346 square degrees(18.6°×18.6°)of the X-ray imager is *** optical assembly composed of 36 MPO chips is used to focus incident X-ray photons,and four large-format complementary metal-oxide semiconductor(CMOS)sensors,each of size 6 cm×6 cm,are used as the focal plane *** instrument has an angular resolution of 4’-8’(in terms of FWhM)for the central focal spot of the point-spread function,and an effective area of 2-3 cm^(2) at 1 keV in essentially all the directions within the field of *** detection passband is 0.5-4 keV in soft X-rays and the sensitivity is2-3×10^(-11) erg s^(-1) cm^(-2)(about 1 milliCrab)with a 1000 s *** total weight of LEIA is 56 kg and the power is 85 *** satellite,with a design lifetime of 2 yr,operates in a Sun-synchronous orbit of 500 km with an orbital period of 95 *** is paving the way for future missions by verifying in flight the technologies of both novel focusing imaging optics and CMOS sensors for X-ray observation,and by optimizing the working setups of the instrumental *** addition,LEIA is able to carry out scientific observations to find new transients and to monitor known sources in the soft X-ray band,albeit with limited useful observing time available.

关键词： instrumentation detectors-space vehicles instruments-telescopes-X-rays genera

AN ERROR ANALySIS METhOD SPP-BEAM AND A CONSTRUCTION GUIDELINE OF NONCONFORMING FINITE ELEMENTS FOR FOURTh ORDER ELLIPTIC PROBLEMS

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Journal of Computational Mathematics 2020年第1期38卷 195-222页

作者： Jun hu Shangyou Zhang LMAM and School of Mathematical Sciences Peking UniversityBeijing 100871China Department of Mathematical Sciences University of DelawareNewarkDE 19716USA

Under two hypotheses of nonconforming finite elements of fourth order elliptic problems,we present a side-patchwise projection based error analysis method(SPP-BEAM for short).Such a method is able to avoid both the regularity condition of exact solutions in the classical error analysis method and the complicated bubble function technique in the recent medius error analysis *** addition,it is universal enough to admit ***,we propose a sufficient condition for these hypotheses by imposing a set of in some sense necessary degrees of freedom of the shape function *** an application,we use the theory to design a P3 second order triangular h2 non-conforming element by enriching two P4 bubble functions and,another P4 second order triangular h2 nonconforming finite element,and a P3 second order tetrahedral h2 non-conforming element by enriching eight P4 bubble functions,adding some more degrees of freedom.

关键词： Nonconforming finite element A priori error analysis Biharmonic equation

Overcoming diffusion-related limitations in semiconductor defect imaging with phonon-plasmon-coupled mode Raman scattering

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Light(Science & Applications) 2018年第1期7卷 854-861页

作者： Changkui hu Qiong Chen Fengxiang Chen T.h.Gfroerer M.W.Wanlass yong Zhang University of North Carolina at Charlotte CharlotteNC 28223USA Wuhan University of Technology WuhanHubei 430070China Davidson College DavidsonNC 28035USA National Renewable Energy Laboratory GoldenCO 80401USA

Carrier diffusion is of paramount importance in many semiconductor devices,such as solar cells,photodetectors,and power *** defects prevent such devices from reaching their full performance *** a large carrier diffusion length indicates high material quality,it also implies increased carrier depletion by an individual extended defect(for instance,a dislocation)and obscures the spatial resolution of neighboring defects using optical *** commonly utilized photoluminescence(PL)imaging,the spatial resolution is dictated by the diffusion length rather than by the laser spot size,no matter the spot is at or below the diffraction ***,we show how Raman imaging of the LO phonon-plasmon-coupled mode can be used to recover the intrinsic spatial resolution of the optical system,and we demonstrate the effectiveness of the technique by imaging defects in GaAs with diffraction-limited optics,achieving a 10-fold improvement in ***,by combining Raman and PL imaging,we can independently and simultaneously determine the spatial dependence of the electron density.h.le density,radiative recombination rate,and non-radiative recombination rate near a dislocation-like defect,which has not been possible using other techniques.

关键词： scattering diffusion defect

Manganese-catalyzed bicyclic annulations of imines and α,β-unsaturated esters via C-h activation

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Science China Chemistry 2016年第10期59卷 1301-1305页

作者： yuanyuan hu Congyang Wang Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and Function Institute of ChemistryChinese Academy of Sciences University of Chinese Academy of Sciences

A manganese-catalyzed bicyclic annulation of imines with α,β-unsaturated esters via C–h activation is described, which provides an expedient access to fused β-lactams in one-step operation with high efficiency and good functional group tolerance. Of note, both ketimines and aldimines are amenable to this transformation. Mechanistic studies have identified a five-membered azamanganacycle as the key reaction intermediate.

关键词： β-lactams imines alkenes manganese C-h activation

Accelerated design and characterization of non-uniform cellular materials via a machine-learning based framework

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npj Computational Materials 2020年第1期6卷 1338-1345页

作者： Chunping Ma Zhiwei Zhang Benjamin Luce Simon Pusateri Binglin Xie Mohammad h.Rafiei Nan hu Department of Mechanical and Aerospace Engineering The Ohio State UniversityColumbusOH 43210USA School of Civil Engineering Harbin Institute of TechnologyHarbinChina School of Civil Engineering and Transportation South China University of TechnologyGuangzhouChina Department of Mechanical Engineering Johns Hopkins UniversityBaltimoreUSA

Cellular materials,widely found in engineered and nature systems,are highly dependent on their geometric arrangement.A nonuniform arrangement could lead to a significant variation of mechanical properties while bringing challenges in material ***,this proof-of-concept study demonstrates a machine-learning based framework with the capability of accelerated characterization and pattern *** showed that the proposed framework is capable of predicting the mechanical response curve of any given geometric pattern within the design domain under appropriate neural network architecture and ***,the framework is capable of generating matching geometric patterns for a targeted response through a databank constructed from our machine learning *** accuracy of the predictions was verified with finite element simulations and the sources of errors were ***,our machine-learning based framework can boost the design efficiency of cellular materials at unit level,and open new avenues for the programmability of function at system level.

关键词： arrangement characterization pattern

STEADy-STATE CREEP OF UNIDIRECTIONAL C/C COMPOSITE WITh PyROLyTIC CARBON MATRIX

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Acta Metallurgica Sinica(English Letters) 1998年第6期11卷 412-416页

作者： R.Shi G.X.hu h.J.Li M.K.Kang Shanghai Jiaotong Univ Shanghai China

The steady-state creep behavior of unidirectional C/C(1-D-C/C) composite with pyrolytic carbon matrix was investigated at high temperatures up to 2160℃ and under tensile stress from 133.83 to 213.46MPa. Based on the creep experiment of single specimen method, the apparent activation energy and the stress exponent for steadystate creep were determined by the use of a self-made apparatus and an auto-testing system. Value of apparent activation volume is provided and the creep mechanism has also been discussed.

关键词： 1-D-C/C steady-state creep thermal activation

Excitation and detection of coherent sub-terahertz magnons in ferromagnetic and antiferromagnetic heterostructures

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npj Computational Materials 2022年第1期8卷 1606-1614页

作者： Shihao Zhuang Jia-Mian hu Department of Materials Science and Engineering University of Wisconsin-MadisonMadisonWI53706USA

Excitation of coherent high-frequency magnons(quanta of spin waves)is critical to the development of high-speed magnonic *** we computationally demonstrate the excitation of coherent sub-terahertz(Thz)magnons in ferromagnetic(FM)and antiferromagnetic(AFM)thin films by a photoinduced picosecond acoustic *** calculations are also performed to reveal the magnon excitation *** spin pumping and spin-charge conversion,these magnons can inject sub-Thz charge current into an adjacent heavy-metal film which in turn emits electromagnetic(EM)*** a dynamical phase-field model that considers the coupled dynamics of acoustic waves,spin waves,and EM waves,we show that the emitted EM wave retains the spectral information of all the sub-Thz magnon modes and has a sufficiently large amplitude for near-field *** predictions indicate that the excitation and detection of sub-Thz magnons can be realized in rationally designed FM or AFM thin-film heterostructures via ultrafast optical-pump Thz-emission-probe spectroscopy.

关键词： pumping pump coherent

MicroRNAs:new players in the DNA damage response

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Journal of Molecular Cell Biology 2011年第3期3卷 151-158页

作者： hailiang hu Richard A.Gatti Department of Pathology and Laboratory Medicine David Geffen School of Medicine at UCLALos AngelesCA 90095-1732USA Department of human Genetics David Geffen School of Medicine at UCLALos AngelesCA 90095-1732USA

The DNA damage response(DDR)is a signal transduction pathway that decides the cell’s fate either to repair DNA damage or to undergo apoptosis if there is too much ***-translational modifications modulate the assembly and activity of protein complexes during the DDR ***(miRNAs)are emerging as a class of endogenous gene modulators that control protein levels,thereby adding a new layer of regulation to the *** this review,we describe a new role for miRNAs in regulating the cellular response to DNA damage with a focus on DNA double-strand break *** also discuss the implications of miRNA’s role in the DDR to stem cells,including embryonic stem cells and cancer stem cells,stressing the potential applications for miRNAs to be used as sensitizers for cancer radiotherapy and chemotherapy.

关键词： microRNA DNA damage response radiosensitivity stem cells

A novel localization and orientation method for an objective embedded with a rectangle magnet

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high Technology Letters 2011年第1期17卷 39-45页

作者：阳万安 hu Chao Max Q. - h. Meng Song Shuang Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 P. R.China Shenzhen Institute of Advanced Integration Technology Chinese Academy of Sciences/The Chinese University of Hong Kong Shenzhen Institute of Advanced Technology CAS Shenzhen 518067 P. R. China Department of Electronic Engineering the Chinese University of Hong Kong Shatin Hong Kong China Graduate University of the Chinese Academy of Sciences Beijing P. R. China Department of Computer and Information Science Yi Bin University Yibin 644000 P. R. China

To wirelessly obtain the accurate location and orientation of an objective and exert an appropriate guidance for the objective, a feasible approach is to enclose a small rectangular permanent mag- net in the objective. The magnetic field, produced by the rectangular magnet can be detected by magnetic sensors outside the objective. With these sensor data, the 3D localization and 3D orienta- tion parameters can be computed based on the mathematic model of the rectangular magnet magnetic field. In this 6D localization and orientation system, we first obtain 5D parameters of the objective by dipole model, then based on these parameters we can obtain 6D parameters by the model of rectangular magnet magnetic field using the particle swarm optimization （PSO） algorithm. Simulation experiments show that the proposed approach achieves ~ood performance.

关键词： index terms -dipole 6D localization and orientation rectangular magnet PSO algorithm