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SMILE soft X-ray Imager flight model CCD370 pre-flight device characterisation

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Earth and Planetary Physics 2024年第1期8卷 25-38页

作者： S.Parsons D.J.Hall O.Hetherington T.W.Buggey T.Arnold M.W.J.hubbard A.Holland Centre for Electronic Imaging the Open UniversityMilton KeynesMK76AAUK

Throughout the SMILE mission the satellite will be bombarded by radiation which gradually damages the focal plane devices and degrades their *** order to understand the changes of the CCD370s within the soft X-ray Imager,an initial characterisation of the devices has been carried out to give a baseline performance *** CCDs have been characterised,the two flight devices and the flight spa *** has been carried out at the Open University in a bespo ke cleanroom measure ment *** results show that there is a cluster of bright pixels in the flight spa re which increases in size with tempe *** at the nominal ope rating tempe rature(-120℃) it is within the procure ment ***,the devices meet the specifications when ope rating at -120℃ in 6 × 6 binned frame transfer science *** se rial charge transfer inefficiency degrades with temperature in full frame *** any charge losses are recovered when binning/frame transfer is implemented.

关键词： CCD soft X-ray imager characterisation SMILE

The CCD instrument background of the SMILE SXI

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Earth and Planetary Physics 2024年第1期8卷 15-24页

作者： M.W.J.hubbard O.Hetherington D.J.Hall T.W.Buggey S.Parsons T.Arnold A.Holland C.Pagani S.Sembay Centre for Electronic Imaging The Open UniversityMilton KeynesMK76AAUK X-ray and Observational Astronomy group Department of Physics&AstronomyUniversity of LeicesterLE17RHUK

The ESA and CAS SMILE mission orbit is highly elliptical and will pass through multiple radiation *** Soft X-ray Imager(SXI)instrument aboard has a radiation shutter door designed to close when the surrounding radiation flux is *** shutter door will close when passing below an altitude threshold to protect against trapped particles in the Earth’s Van Allen ***,two radiation environments can be approximated based on the shutter door position:open and *** instrument background for the CCDs(Charge-Coupled Devices)that form the focal plane array of the SXI were evaluated for the two *** to the correlation of the space environment with the solar cycle,the solar minima and maxima,the background was also evaluated at these two *** results demonstrated that the highest instrument background will occur during solar minima due to the main contributing source being galactic Cosmic Rays(gCRs).It was also found that the open background was highest for solar minima and that the closed background was highest during solar *** is due to the radiation shutter door acting as a scattering centre and the changes in the energy flux distribution of the gCRs between the two solar extremes.

关键词： instrument background X-ray astronomy space radiation

The Soft X-ray Imager(SXI)on the SMILE Mission

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Earth and Planetary Physics 2024年第1期8卷 5-14页

作者： S.Sembay A.L.Alme D.Agnolon T.Arnold A.Beardmore A.Belén Balado Margeli C.Bicknell C.Bouldin g.Branduardi-Raymont T.Crawford J.P.Breuer T.Buggey g.Butcher R.Canchal J.A.Carter A.Cheney Y.Collado-Vega H.Connor T.Crawford N.Eaton C.Feldman C.Forsyth T.Frantzen g.galgóczi J.garcia g.Y.genov C.gordillo H-P.gröbelbauer M.guedel Y.guo M.Hailey D.Hall R.Hampson J.Hasiba O.Hetherington A.Holland S-Y.Hsieh M.W.J.hubbard H.Jeszenszky M.Jones T.kennedy k.koch-Mehrin S.kögl S.krucker k.D.kuntz C.Lakin g.Laky O.Lylund A.Martindale J.Miguel Mas Hesse R.Nakamura k.Oksavik N.Østgaard H.Ottacher R.Ottensamer C.Pagani S.Parsons P.Patel J.Pearson g.Peikert F.S.Porter T.Pouliantis B.H.Qureshi W.Raab g.Randal A.M.Read N.M.M.Roque M.E.Rostad C.Runciman S.Sachdev A.Samsonov M.Soman D.Sibeck S.Smit J.Søndergaard R.Speight S.Stavland M.Steller TianRan Sun J.Thornhill W.Thomas k.Ullaland B.Walsh D.Walton C.Wang S.Yang School of Physics and Astronomy University of LeicesterLeicesterLE17RHUK Space Park Leicester University of LeicesterLeicesterLE17RHUK Mullard Space Science Laboratory University College LondonDorkingRH56NTUK Centre for Electronic Imaging Open UniversityMilton KeynesMK76 AAUK Birkeland Centre for Space Science Department of Physics and TechnologyUniv.of BergenN-5007 BergenNorway University of Vienna A-1010 ViennaAustria Space Research Institute Austrian Academy of SciencesA-8042 GrazAustria National Institute of Aerospace Technology MadridSpain ESTEC European Space Agency2201 AZ NoordwijkNetherlands State key Laboratory of Space Weather National Space Science CentreBeijing 100190China University of Applied Sciences and Arts Northwestern Switzerland CH-5210 WindischSwitzerland koegl Space gmbH CH-8157 DielsdorfSwitzerland Space Acoustics gmbH CH-8157 DielsdorfSwitzerland Zurich University of Applied Sciences 8400 WinterhurSwitzerland genov Solutions N-5172 LoddefjordNorway STM Engineering N-5165 LaksevagNorway John Hopkins University Applied Physics Laboratory MD 20723USA NASA/goddard Space Flight Centre MD 20771USA Center for Space Physics Boston UniversityBostonMA 02215USA Department of Theoretical Physics and Astrophysics Masaryk University60177 BrnoCzech Republic Institute of Physics E¨otvo¨s Lor´and University1053 BudapestHungary Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100045China Centro de Astrobiologia(CAB) CSIC-INTAMadridSpain

The Soft X-ray Imager(SXI)is part of the scientific payload of the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)*** is a joint science mission between the European Space Agency(ESA)and the Chinese Academy of Sciences(CAS)and is due for launch in *** is a compact X-ray telescope with a wide field-of-view(FOV)capable of encompassing large portions of Earth’s magnetosphere from the vantage point of the SMILE *** is sensitive to the soft X-rays produced by the Solar Wind Charge eXchange(SWCX)process produced when heavy ions of solar wind origin interact with neutral particles in Earth’s *** provides a mechanism for boundary detection within the magnetosphere,such as the position of Earth’s magnetopause,because the solar wind heavy ions have a very low density in regions of closed magnetic field *** sensitivity of the SXI is such that it can potentially track movements of the magnetopause on timescales of a few minutes and the orbit of SMILE will enable such movements to be tracked for segments lasting many *** is led by the University of Leicester in the United kingdom(Uk)with collaborating organisations on hardware,software and science support within the Uk,Europe,China and the United States.

关键词： Soft X-ray Imaging micropore optics large area CCD

Velocity-Based Moving Mesh Methods for Nonlinear Partial Differential Equations

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Communications in Computational Physics 2011年第8期10卷 509-576页

作者： M.J.Baines M.E.hubbard P.k.Jimack Department of Mathematics The University of ReadingRG66AXUK. School of Computing University of LeedsLS29JTUK

This article describes a number of velocity-based moving mesh numerical methods for multidimensional nonlinear time-dependent partial differential equations(PDEs).It consists of a short historical review followed by a detailed description of a recently developed multidimensional moving mesh finite element method based on *** element algorithms are derived for both mass-conserving and non mass-conserving problems,and results shown for a number of multidimensional nonlinear test problems,including the second order porous medium equation and the fourth order thin film equation as well as a two-phase *** applications and extensions are referenced.

关键词： Time-dependent nonlinear diffusion moving boundaries finite element method Lagrangian meshes conservation of mass

A Moving-Mesh Finite Element Method and its Application to the Numerical Solution of Phase-Change Problems

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Communications in Computational Physics 2009年第8期6卷 595-624页

作者： M.J.Baines M.E.hubbard P.k.Jimack R.Mahmood Department of Mathematics The University of ReadingUK School of Computing University of LeedsUK Computer Division Pakistan Institute of Nuclear Science and Technology(PINSTECH)IslamabadPakistan

A distributed Lagrangian moving-mesh finite element method is applied to problems involving changes of *** algorithm uses a distributed conservation principle to determine nodal mesh velocities,which are then used to move the *** nodal values are obtained from an ALE(Arbitrary Lagrangian-Eulerian)equation,which represents a generalization of the original algorithm presented in Applied Numerical Mathematics,54:450–469(2005).Having described the details of the generalized algorithm it is validated on two test cases from the original paper and is then applied to one-phase and,for the first time,two-phase Stefan problems in one and two space dimensions,paying particular attention to the implementation of the interface boundary *** are presented to demonstrate the accuracy and the effectiveness of the method,including comparisons against analytical solutions where available.

关键词： Moving mesh method finite elements multiphase flows interface tracking

Acknowledgment of Libraries in the Journal Literature: An Exploratory Study

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Journal of Data and Information Science 2020年第3期5卷 178-186页

作者： David E.hubbard Sierra Laddusaw Texas A&M University University LibrariesTAMU 5000 College StationTexas 77843USA

Purpose: This study examines acknowledgments to libraries in the journal literature, as well as the efficacy of using Web of Science(WoS) to locate general acknowledgment ***/methodology/approach: This mixed-methods approach quantifies and characterizes acknowledgments to libraries in the journal literature. Using WoS's Funding Text field, the acknowledgments for six peer universities were identified and then characterized. The efficacy of using WoS to locate library acknowledgments was assessed by comparing the WoS Funding Text search results to the actual acknowledgment text found in the ***: Acknowledgments to libraries were found in articles at all six peer universities, though the absolute and relative numbers were quite low(knowledgments were for resources(collections, funding, etc.), and many were concentrated in natural history(e.g. zoology). Examination of Texas A&M University zoology articles found that 91.7% of the funding information came from "acknowledgments" and not specifically a funding acknowledgment section. The WoS Funding Text search found 56% of the library acknowledgments compared to a search of the actual acknowledgment text in the *** limitations: Limiting publications to journals, using a single truncated search term, and including only six research universities in the United *** implications: This study examined library acknowledgments, but the same approach could be applied to searches of other keywords, institutions/organizations, individuals, etc. While not specifically designed to search general acknowledgments, WoS's Funding Text field can be used as an exploratory tool to search acknowledgments beyond funding. Originality/value: There are a few studies that have examined library acknowledgments in the scholarly literature, though to date none of those studies have examined the efficacy of using the WoS Funding Text field to locate those library acknowledg

关键词： Acknowledgment Bibliometric analysis Libraries Web of Science

A Comparison of Elementary Foreign Language Programs in China and the USA

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Fudan Journal of the Humanities and Social Sciences 2021年第3期14卷 319-344页

作者： Qi Si Janie hubbard Department of Curriculum and Instruction The University of AlabamaBox 870232TuscaloosaAlabama 35487USA

This study presents comparisons regarding current elementary foreign language programs in China and the *** design features a comparative analysis approach combined with deductive thematic analysis to collect,analyze,and compare relevant *** were collected from samples such as governmental documents,organizational guidelines,national statistical reports,published scholarly works,audiovisual materials,and *** the research,primary categories were identified,used to group data,and then look for similarities and *** for comparison were:(a)program types,(b)curriculum standards,(c)instructional methods,and(d)*** indicated US programs could benefit from consistency,widespread support and demand,state-to-state organization and/or alignment,equitable teaching materials,and attention to all student ***'s program,while organized,could benefit from more authentic,real-life-context,other-culture-oriented practices,flexibility,and deeper,genuine information about English-speaking countries’*** research contributes to scholarly conversations regarding comparisons of elementary foreign language teaching in China and the USA,while also supporting worldwide comparisons and exchange of ideas.

关键词： Elementary education Foreign language programs global comparison China and US education

Assessment of widely used methods to derive depositional ages from detrital zircon populations

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geoscience Frontiers 2019年第4期10卷 1421-1435页

作者： Daniel S.Coutts William A.Matthews Stephen M.hubbard Department of geoscience University of Calgary

The calculation of a maximum depositional age(MDA)from a detrital zircon sample can provide insight into a variety of geological ***,the impact of sample size and calculation method on the accuracy of a resulting MDA has not been *** use large populations of synthetic zircon dates(N≈25,000)to analyze the impact of varying sample size(n),measurement uncertainty,and the abundance of neardepositional-age zircons on the accuracy and uncertainty of 9 commonly used MDA calculation ***,a new method,the youngest statistical population is *** each method,500 samples of n synthetic dates were drawn from the parent population and MDAs were *** mean and standard deviation of each method ove r the 500 trials at each n-value(50-1000,in increments of 50)were compa red to the known depositional age of the synthetic population and used to compare the methods quantitatively in two simulation *** first simulation scenario varied the proportion of near-depositional-age grains in the synthetic *** second scenario varied the uncertainty of the dates used to calculate the *** sample size initially decreased the mean residual error and standard deviation calculated by each *** higher n-values(>~300 grains),calculated MDAs changed more slowly and the mean resid ual error increased or decreased depending on the method *** the p roportion of near-depositional-age grains and lowering measurement uncertainty decreased the number of measurements required for the calculated MDAs to stabilize and decreased the standard deviation in calculated MDAs of the 500 *** of the two simulation scenarios show that the most successful way to increase the accuracy of a calculated M DA is by acquiring a large number of low-uncertainty measurements(300300)approach is used if the calculation of accurate MDAs are key to research *** acquisition method s,such as high-to moderate-precision m

关键词： Detrital zircon Maximum depositional age geochronology Basin chronology LA-ICP-MS

Money, the financial system, and the economy / 4th ed.

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