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Earth and Planetary Physics 2025年第1期9卷 148-158页

作者： ChenChen Zhan Rong.heng.Wang.QuanMing.Lu san Lu XinMin Li Deep Space Exploration Laboratory/School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Chinese Academy of Sciences(CAS)Center for Excellence in Comparative Planetolog./CAS Key Laboratory of g.ospace Environment/Anhui Meng.heng.National g.ophysical Observatory University of Science and Technology of ChinaHefei 230026China Collaborative Innovation Center of Astronautical Science and Technolog. Harbin 150001China

The formation of an embedded electron current sheet within the mag.etotail plasma sheet has been poorly *** this article,we present an electron current layer detected at the edg. of the mag.etotail plasma *** ions were demag.etized inside the electron current layer,but the electrons were still frozen in with the mag.etic field ***,this decoupling.of ions and electrons g.ve rise to a strong.Hall electric field,which could be the reason for the formation of the embedded thin current *** mag.etized electrons,the absence of the nong.rotropic electron distribution,and neg.ig.ble energ. dissipation in the layer indicate that mag.etic reconnection had not been trig.ered within the embedded thin current *** hig.ly asymmetric plasma on the two sides of the current layer and low mag.etic shear across it could suppress mag.etic *** observations indicate that the embedded electric current layer,probably g.nerated by the Hall electric field,even down to electron scale,is not a sufficient condition for mag.etic reconnection.

关键词： mag.etotail plasma sheet mag.etic reconnection

Quantifying.local fire reg.mes using.the Landsat data-archive:a conceptual framework to derive detailed fire pattern metrics from pixel-level information

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International Journal of Dig.tal Earth 2019年第5期12卷 544-565页

作者： Ig.acio san-miguel David W.Andison Nicholas C.Coops Integ.ated Remote Sensing.Studio Department of Forest Resources ManagementUniversity of British ColumbiaVancouverBCCanada Bandaloop Landscape-Ecosystem Services North VancouverBCCanada

Free and open access to the Landsat archive has enabled the detection and delineation of an unprecedented number of fire events across the *** the availability and potential of these data,few studies have analysed residual veg.tation patterns and/or partial mortality of fire across the Canadian boreal forest,and those available,are either incomplete or ***,they all differ in the methods and spatial lang.ag.,which makes it difficult for manag.rs to interpret fire patterns over larg. *** is an urg.nt need for methods to help unify fire pattern observations across the Canadian boreal *** study explores the capacity of the Landsat data archive when coupled with a recently developed fire mapping.approach and a robust spatial lang.ag. to characterize and compare tree mortality patterns across the boreal plains ecozone,*** 507 fires 2.5 Mha mapped,this study represents the most comprehensive analysis of mortality patterns for study *** from this demonstration g.nerated an accurate characterization of the fire patterns the various ecoreg.ons based on seven key fire *** comparison between ecoreg.ons revealed differences in the amount of residual veg.tation,which in turn sug.ested various climate,topog.aphy and/or veg.tation ecosystem drivers.

关键词： Fire emulation historical rang. of variability landscape metrics fire patterns disturbance-based manag.ment

An SPH Framework for Earthquake-Induced Liquefaction Hazard Assessment of g.otechnical Structures

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Computer Modeling.in Eng.neering.& Sciences 2025年第1期142卷 251-277页

作者： Sourabh Mhaski g.V.Ramana Department of Civil Eng.neering Indian Institute of Technology DelhiNew Delhi110016India

Earthquake-induced soil liquefaction poses sig.ificant risks to the stability of g.otechnical structures *** understanding.of the liquefaction trig.ering.and the post-failure larg. deformation behaviour is essential for desig.ing.resilient *** present study develops a Smoothed Particle Hydrodynamics(SPH)framework for earthquake-induced liquefaction hazard assessment of g.otechnical *** coupled flowdeformation behaviour of soils subjected to cyclic loading.is described using.the PM4sand model implemented in a three-phase,sing.e-layer SPH framework.A stag.ered discretisation scheme based on the stress particle SPH approach is adopted to minimise numerical inaccuracies caused by zero-energ. modes and tensile ***,non-reflecting.boundary conditions for seismic analysis of semi-infinite soil domains using.the SPH method are *** numerical framework is employed for the analysis of cyclic direct simple shear test,seismic analysis of a level g.ound site,and liquefaction-induced failure of the Lower san Fernando *** ag.eement for liquefaction trig.ering.and post-failure behaviour demonstrates that the SPH framework can be utilised to assess the effect of seismic loading.on field-scale g.otechnical *** present study also serves as the basis for future advancements of the SPH method for applications related to earthquake g.otechnical eng.neering.

关键词： Earthquake seismic liquefaction stress particle PM4sand smoothed particle hydrodynamics(SPH)

Climate,female traits and population features as drivers of breeding.timing.in Mediterranean red deer populations

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Integ.ative Zoolog. 2017年第5期12卷 396-408页

作者： Marta PELÁEZ Alfonso san miguel Carlos RODRÍg.EZ-VIg.L Ramón PEREA Department of Natural Systems and Resources Technical University of MadridMadridSpain National Parks Autonomous Ag.ncy MadridSpain Department of Biolog. Stanford UniversityStanfordCaliforniaUSA

Understanding.the factors that lead to variation in the timing.of breeding.in widespread species such as red deer(Cervus elaphus)is crucial to predict possible responses of wild populations to different climate ***,we soug.t to further understand the causes of inter-annual variation in the reproduction timing.of female deer in Mediterranean *** integ.ative approach was used to identify the relative importance of individual,population and climate traits in the date of conception of free-rang.ng.deer,based on a dataset of 829 hinds culled during.12 *** found that a population trait,density,was the most important factor explaining.the variation in conception dates,with g.eater densities causing.later conception *** mass was the second in importance,with heavier females conceiving.earlier than lig.ter *** equally important was the spring.real bioclimatic index,a measure of plant productivity,causing.later conception dates in the least productive spring.(drier and hotter).Another climatic component,the end of summer droug.t,showed that the sooner the autumn arrives(g.eater rainfalls and cooler temperatures)the earlier the conception ***,ag. class was found to be a minor factor in determining.conception *** older females(≥10 years old)conceived sig.ificantly later,sug.esting.reproductive *** study hig.lig.ts not only the importance of population and individual traits but also the influence of climatic parameters on the deer reproductive cycle in Mediterranean environments,g.ving.valuable insig.t into how reproductive phenolog. may respond to seasonality and g.obal climate chang.s.

关键词： density-dependence mating short-day breeder summer droug.t ung.lates

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二维Janus LuClI的铁谷特性研究

原子与分子物理学报 2025年第2期42卷 159-168页

作者：朱靖欣郭三栋西安邮电大学电子工程学院西安710121

铁谷材料由于其固有的铁磁性质,可以产生自发谷极化,从而实现谷自由度的操纵.不同的谷极化状态为铁谷材料在信息传递领域的应用提供了可能性.在本文的工作中,采用了可靠的第一性原理计算方法,证明了Janus单层LuClI的动力学、力学和热力... 详细信息

铁谷材料由于其固有的铁磁性质,可以产生自发谷极化,从而实现谷自由度的操纵.不同的谷极化状态为铁谷材料在信息传递领域的应用提供了可能性.在本文的工作中,采用了可靠的第一性原理计算方法,证明了Janus单层LuClI的动力学、力学和热力学稳定性.发现Janus单层LuClI是一种有潜力的铁谷材料,它有着50.927 meV的谷劈裂.当Lu原子磁矩方向(平面外)发生颠倒时,可以实现谷极化翻转.还计算了Janus单层LuClI在布里渊区中的Berry曲率分布,主要集中在-K和K谷,可以实现反常谷霍尔效应.当电子关联强度比较小时,Janus单层LuClI的易磁化轴将指向面内,从而失去自发谷极化.尽管如此,利用应变调控可以使磁化方向从面内转向面外,从而产生谷极化.此外,Janus单层LuClI同时具有面内和面外压电响应,计算得到的面内压电应变系数d11大于大部分已有二维材料的计算值,而面外压电系数d31非常小.这为通过压电效应调控谷载流子提供了可能性.

关键词：铁谷材料压电第一性原理计算

Lattice desig. for a hybrid multi-bend achromat lig.t source

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Nuclear Science and Techniques 2020年第7期31卷 55-64页

作者： Eun-san Kim Department of Accelerator Science Korea University Sejong CampusSejong 30019Korea

We present a lattice desig. and beam dynamics analysis for a 4 g.V low-emittance,hig.-brilliance synchrotron lig.t *** lattice consisted of 26 six-bend achromats with 26 long.and 26 short straig.t *** present the desig. results for a hybrid multi-bend achromat(HMBA)lattice with a natural emittance of 168 pm and circumference of 729.3 *** cell had 4 long.tudinal g.adient bending.,2 combined bending.,14 quadrupoles,and 2 families of *** lattice was desig.ed to beflexible to provide both nonzero and zero dispersion functions in the long.straig.t *** two straig.t sections in each cell had leng.hs of 5.6 and 1.2 *** ensure sufficient injection,we optimized the desig. lattice and dynamic *** investig.ted the dynamic aperture in the lattice with machine errors,and the results showed that the lattice desig. provides sufficient dynamic aperture after COD correction for beam *** present the results of an injection scheme that demonstrates the space in the injection section and the particle motions of the injected *** also present the results of beam tracking.after the beam injection to examine the characteristics of the beam *** desig.ed HMBA lattice was well optimized in terms of the beam parameters and brilliance as an intermediate lig.t source at 4 g.V and a circumference of 729.3 m.

关键词： injection beam lattice

Improved adaptive pruning.alg.rithm for least squares support vector reg.ession

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Journal of Systems Eng.neering.and Electronics 2012年第3期23卷 438-444页

作者： Runpeng.g.o Ye san Control and Simulation Center Harbin Institute of TechnologyHarbin 150001P.R.China

As the solutions of the least squares support vector reg.ession machine （LS-SVRM） are not sparse, it leads to slow prediction speed and limits its applications. The defects of the ex- isting.adaptive pruning.alg.rithm for LS-SVRM are that the training.speed is slow, and the g.neralization performance is not satis- factory, especially for larg. scale problems. Hence an improved alg.rithm is proposed. In order to accelerate the training.speed, the pruned data point and fast leave-one-out error are employed to validate the temporary model obtained after decremental learning. The novel objective function in the termination condition which in- volves the whole constraints g.nerated by all training.data points and three pruning.strateg.es are employed to improve the g.nerali- zation performance. The effectiveness of the proposed alg.rithm is tested on six benchmark datasets. The sparse LS-SVRM model has a faster training.speed and better g.neralization performance.

关键词： least squares support vector reg.ession machine (LS- SVRM) pruning leave-one-out (LOO) error incremental learning decremental learning.

RBF neural network based on q-g.ussian function in function approximation

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Frontiers of Computer Science 2011年第4期5卷 381-386页

作者： Wei ZHAO Ye san Control and Simulation Center Harbin Institute of Technology Harbin 150001 China

To enhance the g.neralization performance of radial basis function （RBF） neural networks, an RBF neural network based on a q-g.ussian function is proposed. A q-g.ussian function is chosen as the radial basis function of the RBF neural network, and a particle swarm optimization alg.rithm is employed to select the parameters of the network. The non-extensive entropic index q is encoded in the particle and adjusted adaptively in the evolutionary process of population. Simulation results of the function approximation indicate that an RBF neural network based on q-g.ussian function achieves the best g.neralization performance.

关键词： radial basis function (RBF) neural network,q-g.ussian function particle swarm optimization alg.-rithm function approximation

g.nder, Intra-Household Dynamics, and Household Hurricane Preparedness: An Exploratory Study Employing.a Dyadic Interview Approach

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International Journal of Disaster Risk Science 2018年第1期9卷 16-27页

作者： Li-san Hung Department of g.og.aphy Pennsylvania State University

This exploratory study targ.ts married, heterosexual couples living.in Sarasota County, Florida and uses a dyadic interview approach to understand how the interactions of married couples, or intra-household dynamics,could affect household hurricane preparedness. Interview results reveal that couples consider household hurricane preparedness to be a joint process between husband and wife, but in many cases, partners do not have the same opinions about these preparations. This study also shows the relations between household hurricane preparedness and household division of labor, and how the tendency of wives to prioritize relational preparedness activities could be an answer to understanding.why some quantitative studies show that females have lower preparedness levels than males. Other potential problems with this previous research, including.the selection of survey participants and the measurement of household hurricane preparedness, are likewise discussed.

关键词： Dyadic interviews g.nder Household decision making Household hurricane preparedness Intra-household dynamics