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A molecular dynamics study of laser-excited gold

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matter and Radiation at Extremes 2022年第3期7卷 20-30页

作者： Jacob m.molina T.G.White University of Nevada RenoNevada 89557USA

The structural evolution of laser-excited systems of gold has previously been measured through ultrafast meV electron ***,there has been a long-standing inability of atomistic simulations to provide a consistent picture of the melting process,leading to large discrepancies between the predicted threshold energy density for complete melting,as well as the transition between heterogeneous and homogeneous *** make use of two-temperature classical molecular dynamics simulations utilizing three highly successful interatomic potentials and reproduce electron diffraction data presented by mo et al.[Science 360,1451–1455(2018)].We recreate the experimental electron diffraction data,employing both a constant and temperature-dependent electron–ion equilibration *** all cases,we are able to match time-resolved electron diffraction data,and find consistency between atomistic simulations and experiments,only by allowing laser energy to be transported away from the interaction *** additional energy-loss pathway,which scales strongly with laser fluence,we attribute to hot electrons leaving the target on a timescale commensurate with melting。

关键词： diffraction. excited dynamics

一种热控制器紧固件连接的安全分析与校验研究

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机械科学与技术 2008年第9期27卷 1146-1150页

作者：闫法义程林朱新军郑继周 m.molina 山东大学热科学与工程研究中心济南250061 Carlo Gavazzi Space S. p. A. milano Italy 20151

以大型航天探测器AmS-02热控制系统结构测试件的连接为例,研究了航天器紧固件连接的安全校验方法。简化了热控制系统的有限元模型,通过大型有限元分析软件NASTRAN分析了施加在各连接紧固件上的轴向力和合成力。根据NASA提供的校验准则,... 详细信息

以大型航天探测器AmS-02热控制系统结构测试件的连接为例,研究了航天器紧固件连接的安全校验方法。简化了热控制系统的有限元模型,通过大型有限元分析软件NASTRAN分析了施加在各连接紧固件上的轴向力和合成力。根据NASA提供的校验准则,计算得到了各类连接的安全裕度值。对于部分安全裕度值小于零的连接处,应更换强度更大的紧固件并重新进行安全校验,为航天器的最终设计提供了依据。

关键词：航天器 AmS-02 紧固件有限元分析安全裕度

ON THE IDENTIFICATION OF RESIDUAL ImPACT PROPERTIES OF mATERIALS BY ACOUSTO-ULTRASONICS——A PATTERN RECOGNITION APPROACH

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Acta mechanica Sinica 1995年第1期11卷 34-43页

作者： G.J.molina Y.m.Haddad Dept.of mechanical Engineering University of OttawaOttawaCanada K1N 6N5

This paper deals with the application of Acousto-ultrasonics,in con- junction with Pattern Recognition and Classification techniques,to the identification of residual impact properties of a class of polymeric material,namely,Polyvinylchlo- ride(PVC).PVC specimens of different low-energy repeated impact damage states are processed by Acousto-ultrasonics(AU)to retrieve AU signals in the form of dig- italized *** AU signals are grouped as distinct classes,each pertaining to a known level of repeated impact *** features of these AU signals are used to build Pattern Recognition(PR)*** classifiers are used to identify unknown damage states in other PVC specimens by classifying the re- trieved AU signals as belonging to one of the *** obtained results indicate that Acousto-ultrasonics in combination with Pattern Recognition and Classification techniques can be used for the quantitative non-destructive identification of damage states in PVC specimens of unknown low-energy repeated impact conditions.

关键词： pattern recognition acousto-ultrasonics impact damage quantitative non-destructive examination

Alternative approaches for estimating missing climate data:application to monthly precipitation records in South- Central Chile

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Forest Ecosystems 2018年第4期5卷 390-399页

作者： Alonso barrios Guillermo Trincado Rene Garreaud Escuela de Graduados Facultad de Ctencias Forestales y Recursos Naturales Universidad Austral de ChileBox 567ValdiviaChile Departamento de Ciencias Forestales Facuitad de Ingenieria ForestalUnlversidad del Tolima Box 6299 Ibague Colombia Instituto de Bosques y Sociedad Facultad de Ciencias Forestales y Recursos NaturalesUniversidad Austraide ChileBox 567 ValdiviaChile Departamento de Geofistca Facultad de Ciencias Fisicas y MatematicasUniversidad de ChileSantiagoChile

Background: Over the last decades interest has grown on how climate change impacts forest resources. However,one of the main constraints is that meteorological stations are riddled with missing climatic data. This study compared five approaches for estimating monthly precipitation records: inverse distance weighting(IDW), a modification of IDW that includes elevation differences between target and neighboring stations(IDW_m), correlation coefficient weighting(CCW), multiple linear regression(mLR) and artificial neural networks(ANN).methods: A complete series of monthly precipitation records(1995-2012) from twenty meteorological stations located in central Chile were used. Two target stations were selected and their neighboring stations, located within a radius of25 km(3 stations) and 50 km(9 stations), were identified. Cross-validation was used for evaluating the accuracy of the estimation approaches. The performance and predictive capability of the approaches were evaluated using the ratio of the root mean square error to the standard deviation of measured data(RSR), the percent bias(PBIAS), and the NashSutcliffe efficiency(NSE). For testing the main and interactive effects of the radius of influence and estimation approaches,a two-level factorial design considering the target station as the blocking factor was ***: ANN and mLR showed the best statistics for all the stations and radius of influence. However, these approaches were not significantly different with IDW_m. Inclusion of elevation differences into IDW significantly improved IDW_m estimates. In terms of precision, similar estimates were obtained when applying ANN, mLR or IDW_m, and the radius of influence had a significant influence on their estimates, we conclude that estimates based on nine neighboring stations located within a radius of 50 km are needed for completing missing monthly precipitation data in regions with complex ***: It is concluded that approaches based on ANN

关键词： Climatological data Cross-validation Artificial neural networks multiple linear regression

A NETWORK ANALYSIS OF THE 2010 FIFA WORLD CUP CHAmPION TEAm PLAY

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Journal of Systems Science & Complexity 2013年第1期26卷 21-42页

作者： COTTA Carlos mORA Antonio m mERELO Juan Julin mERELO-molina Cecilia Department of Computer Science University of Mlaga Department of Architecture and Computer Technology University of Granada

This paper analyzes the network of passes among the players of the Spanish team during the last FIFA World Cup 2010,where they emerged as the champion,with the objective of explaining the results obtained from the behavior at the complex network *** team is considered a network with players as nodes and passes as(directed) edges.A temporal analysis of the resulting passes network is also done,looking at the number of passes,length of the chain of passes,and to network measures such as player centrality and clustering *** of the last three matches(the decisive ones) indicate that the clustering coefficient of the pass network remains high,indicating the elaborate style of the Spanish *** effectiveness of the opposing team in negating the Spanish game is reflected in the change of several network measures over time,most importantly in drops of the clustering coefficient and passing length/speed,as well as in their being able in removing the most talented players from the central positions of the ***'s ability to restore their combinative game and move the focus of the game to offensive positions and talented players is shown to tilt the balance in favor of the Spanish team.

关键词： Complex network complex systems FIFA World Cup football La Roja network analysis soccer Spanish team sports.

machine learning-based zero-touch network and service management:a survey

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Digital Communications and Networks 2022年第2期8卷 105-123页

作者： Jorge Gallego-madrid ramon Sanchez-Iborra Pedro m.Ruiz Antonio F.Skarmeta Department of Information and Communication Engineering University of Murcia30100MurciaSpain Department of Engineering and Applied Techniques University Center of Defense30729San Javier Air Force BaseSpain

The exponential growth of mobile applications and services during the last years has challenged the existing network ***,the arrival of multiple management solutions to cope with this explosion along the end-to-end network chain has increased the complexity in the coordinated orchestration of different segments composing the whole *** Zero-touch Network and Service management(ZSm)concept has recently emerged to automatically orchestrate and manage network resources while assuring the Quality of Experience(QoE)demanded by *** Learning(mL)is one of the key enabling technologies that many ZSm frameworks are adopting to bring intelligent decision making to the network management *** paper presents a comprehensive survey of the state-of-the-art application of mL-based techniques to improve ZSm *** this end,the main related standardization activities and the aligned international projects and research efforts are deeply *** this dissection,the skyrocketing growth of the ZSm paradigm can be ***,different standardization bodies have already designed reference architectures to set the foundations of novel automatic network management functions and resource *** with these advances,diverse mL techniques are being currently exploited to build further ZSm developments in different aspects,including multi-tenancy management,traffic monitoring,and architecture coordination,among ***,different challenges,such as the complexity,scalability,and security of mL mechanisms,are also identified,and future research guidelines are provided to accomplish a firm development of the ZSm ecosystem.

关键词： Zero-touch network and service management(ZSm) Next generation networks(NGN) Artificial intelligence(AI) machine learning(mL)

Soil fertilization does not alter plant architectural effects on arthropod communities

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Journal of Plant Ecology 2017年第5期10卷 800-807页

作者： m.Noelia barrios-Garcia mariano A.Rodriguez-Cabal Jennifer A.Rudgers Gregory m.Crutsinger CONICET CENAC-APNFagnano 244BarilocheRio Negro CP.8400Argentina Grupo de Ecología de Invasiones INIBIOMA-CONICETUniversidad Nacional del ComahueAv.de los Pioneros 2350BarilocheRio Negro CP.8400Argentina Department of Biology University of New MexicoCastetter Hall 286AlbuquerqueNM 87131USA Department of Zoology University of British Columbia#4200-6270 University Blvd.VancouverBritish Columbia V6T 1Z4Canada

Aims While a growing number of studies have demonstrated the impor-tance of intraspecific differences within plant species on associ-ated arthropod communities,little is known regarding the relative strength of these effects compared to environmental *** this study,we examined whether intraspecific plant differences and nutrient fertilization interact to shape the arthropod community of a dominant coastal shrub,Baccharis pilularis(coyote bush).methods We overlaid a fertilization treatment on a 12-year-old common garden experiment planted with erect and prostrate architectural morphs of Baccharis in california,*** collect the associated arthropod community,we vacuum sampled the crown of each Baccharis and identified individuals to species or *** Findings We found that arthropod richness and abundance were 2-to 3-fold greater on prostrate Baccharis than on erect morphs,but observed no main effects of fertilizer addition on the over-all arthropod *** responded as strongly as herbivores to plant morph,and both were unaffected by nutrient *** the specialist stem galler,Gnorimoschema bac-charisella,showed an interactive response to plant morph and ***,phosphorous and potassium addition had opposite effects on the two morphs,increasing stem gall abun-dance by 50%on prostrate morphs,but reducing galling by 20%on erect *** architectural complexity of prostrate morphs could be the driving mechanism of differences in arthropod ***,our results demonstrate that communitylevel consequences of intraspecific differences in plants are strong,rather than being context dependent,and are generally maintained under different resource *** growing number of studies showing strong genotype than nutrient effects on associated arthropod communities suggests that this might be a generalized pattern.

关键词： Baccharis pilularis community genetics G×E interactions galling insects nutrient fertilization

Neurogenesis dynamics in the olfactory bulb:deciphering circuitry organization, function, and adaptive plasticity

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Neural Regeneration Research 2025年第6期20卷 1565-1581页

作者： moawiah m.Naffaa Department of Psychology and Neuroscience Duke UniversityDurhamNCUSA Department of Cell Biology Duke University School of MedicineDurhamNCUSA

Adult neurogenesis persists after birth in the subventricular zone, with new neurons migrating to the granule cell layer and glomerular layers of the olfactory bulb, where they integrate into existing circuitry as inhibitory interneurons. The generation of these new neurons in the olfactory bulb supports both structural and functional plasticity, aiding in circuit remodeling triggered by memory and learning processes. However, the presence of these neurons, coupled with the cellular diversity within the olfactory bulb, presents an ongoing challenge in understanding its network organization and function. moreover,the continuous integration of new neurons in the olfactory bulb plays a pivotal role in regulating olfactory information processing. This adaptive process responds to changes in epithelial composition and contributes to the formation of olfactory memories by modulating cellular connectivity within the olfactory bulb and interacting intricately with higher-order brain regions. The role of adult neurogenesis in olfactory bulb functions remains a topic of debate. Nevertheless, the functionality of the olfactory bulb is intricately linked to the organization of granule cells around mitral and tufted cells. This organizational pattern significantly impacts output, network behavior, and synaptic plasticity, which are crucial for olfactory perception and memory. Additionally, this organization is further shaped by axon terminals originating from cortical and subcortical regions. Despite the crucial role of olfactory bulb in brain functions and behaviors related to olfaction, these complex and highly interconnected processes have not been comprehensively studied as a whole. Therefore, this manuscript aims to discuss our current understanding and explore how neural plasticity and olfactory neurogenesis contribute to enhancing the adaptability of the olfactory system. These mechanisms are thought to support olfactory learning and memory, potentially through increased

关键词： network adaptability neurogenesis neuronal communication olfactory bulb olfactory learning olfactory memory synaptic plasticity

mitochondria–cGAS–STING axis is a potential therapeutic target for senescence-dependent inflammaging-associated neurodegeneration

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Neural Regeneration Research 2025年第3期20卷 805-807页

作者： Josém.Izquierdo Centro de Biología molecular Severo Ochoa(CBm) Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid(CSIC-UAM)MadridSpain

The word “senescence” comes from the Latin senescens, meaning “to begin to age”, and is characterized by a long-lasting but reversible block in proliferation, resulting from stress-induced cell cycle arrest of pre... 详细信息

关键词： Latin potential lasting