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Transfer learning framework for multi-scale crack type classification with sparse microseismic networks

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International Journal of Mining Science and Technology 2024年第2期34卷 167-178页

作者： arnold Yuxuan Xie Bing QLi Department of Civil and Environmental Engineering Western UniversityLondon N6A 3K7Canada

Rock fracture mechanisms can be inferred from moment tensors(MT)inverted from microseismic ***,MT can only be inverted for events whose waveforms are acquired across a network of *** is limiting for underground mines where the microseismic stations often lack azimuthal ***,there is a need for a method to invert fracture mechanisms using waveforms acquired by a sparse microseismic ***,we present a novel,multi-scale framework to classify whether a rock crack contracts or dilates based on a single *** framework consists of a deep learning model that is initially trained on 2400000+manually labelled field-scale seismic and microseismic waveforms acquired across 692 *** learning is then applied to fine-tune the model on 300000+MT-labelled labscale acoustic emission waveforms from 39 individual experiments instrumented with different sensor layouts,loading,and rock types in *** optimal model achieves over 86%F-score on unseen waveforms at both the lab-and *** model outperforms existing empirical methods in classification of rock fracture mechanisms monitored by a sparse microseismic *** facilitates rapid assessment of,and early warning against,various rock engineering hazard such as induced earthquakes and rock bursts.

关键词： Multi-scale Fracture processes Microseismic Acoustic emission Source mechanism Deep learning

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

Predictors of the placebo response in a nutraceutical randomized controlled trial for depression

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Journal of Integrative Medicine 2024年第1期22卷 46-53页

作者： Rosemary arnold Jenifer Murphy-Smith Chee H.Ng David Mischoulon Gerard J.Byrne Chad A.Bousman Con Stough Michael Berk Jerome Sarris Professorial Unit the Melbourne ClinicDepartment of PsychiatryUniversity of MelbourneRichmond 3121Australia Depression Clinical and Research Program Department of PsychiatryMassachusetts General HospitalHarvard Medical SchoolBostonMA 02115USA Faculty of Medicine Discipline of PsychiatryCentre for Clinical ResearchRoyal Brisbane&Women’s HospitalHerstonthe University of QueenslandBrisbane 4006Australia Departments of Medical Genetics PsychiatryPhysiology&Pharmacology and Community Health SciencesUniversity of CalgaryCalgaryAB T2N 1N4Canada Department of Psychiatry the University of MelbourneMelbourne 3052Australia Centre for Human Psychopharmacology Swinburne UniversityMelbourne 3122Australia The Institute for Mental and Physical Health and Clinical Translation School of MedicineBarwon HealthDeakin UniversityGeelong 3220Australia The Centre of Excellence in Youth Mental Health the University of MelbourneParkville 3052Australia Florey Institute of Neuroscience and Mental Health the University of MelbourneParkville 3052Australia NICM Health Research Institute Western Sydney UniversityWestmeadNSW 2145Australia

Objective The placebo response in depression studies is the change in symptoms amongst those who receive an inactive *** well-designed randomized controlled trials(RCTs)of depression have a high proportion of placebo responders,with little understanding as to *** present study assesses characteristics associated with the placebo response in a nutraceutical trial with a large proportion of placebo *** This is a secondary analysis of a nutraceutical depression RCT which identified no overall treatment benefit relative to placebo(n=69 in placebo group).we investigated participant characteristics such as socio-demographics,clinical features,and recruitment methods,and their association with the placebo *** genetic polymorphisms were also *** response was measured based on change in Montgomery-Asberg Depression Rating Scale *** association of these hypothesis-driven variables of interest and the placebo response was examined using linear mixed effects *** Greater levels of education,particularly pursuing post-high school education,better self-reported general health,marriage/de facto,greater improvement in the first trial week,and more failed antidepressant therapies in the current depressive episode were associated with greater placebo *** increased placebo response was not found in those recruited via social media nor in those with concomitant antidepressant *** nucleotide polymorphisms from the tryptophan hydroxylase 1(TPH1)gene(A779C and A218C)were weakly associated with greater placebo response,although the evidence was attenuated after accounting for multiple *** This is,to our knowledge,the first study within nutraceutical research for depression to assess the association between participant characteristics and variation in the placebo *** variables appeared to predict the placebo *** findings may encourage future trial design

关键词： Randomized controlled trial Placebo Depression Nutraceutical Psychiatry

Superplasticity of fine-grained Mg-10Li alloy prepared by severe plastic deformation and understanding its deformation mechanisms

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Journal of Magnesium and Alloys 2024年第1期12卷 316-331页

作者： H.T.Jeong S.w.Lee w.J.Kim Department of Materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

The superplastic behavior and associated deformation mechanisms of a fine-grained Mg-10.1 Li-0.8Al-0.6Zn alloy(LAZ1011)with a grain size of 3.2μm,primarily composed of the BCCβphase and a small amount of the HCPαphase,were examined in a temperature range of 473 K to 623 *** microstructural refinement of this alloy was achieved by employing high-ratio differential speed *** best superplasticity was achieved at 523 K and at strain rates of 10^(-4)-5×10^(-4)s^(-1),where tensile elongations of 550±600%were *** the heating and holding stage of the tensile samples prior to tensile loading,a significant increase in grain size was observed at temperatures above 573 ***,it was important to consider this effect when analyzing and understanding the superplastic deformation behavior and *** the investigated strain rate range,the superplastic flow at low strain rates was governed by lattice diffusion-controlled grain boundary sliding,while at high strain rates,lattice diffusion-controlled dislocation climb creep was the rate-controlling deformation *** was concluded that solute drag creep is unlikely to *** the late stages of deformation at 523 K,it was observed that grain boundary sliding led to the agglomeration of theαphase,resulting in significant strain *** mechanism maps were constructed forβ-Mg-Li alloys in the form of 2D and 3D formats as a function of strain rate,stress,temperature,and grain size,using the constitutive equations for various deformation mechanisms derived based on the data of the current tests.

关键词： Magnesium-lithium alloy Superplasticity Severe plastic deformation Grain size Grain growth

晚白垩世真兽类Zalamdalestes揭示哺乳动物独特的枢椎及其复杂的进化过程

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Science Bulletin 2024年第11期69卷 1767-1775页

作者： Patrick arnold Katarzyna Janiszewska 李茜 Jingmai K.O'Connor Lucja Fostowicz-Frelik Institute of Biochemistry and Biology University of PotsdamPotsdam D-14476Germany Environmental Paleobiology Department Institute of PaleobiologyPolish Academy of SciencesWarsaw 00-818Poland Key Laboratory of Evolutionary Systematics of Vertebrates Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China The Field Museum of Natural History Chicago IL 60605USA Department of Organismal Biology and Anatomy The University of ChicagoChicago IL 60637USA Evolutionary Paleobiology Department Institute of PaleobiologyPolish Academy of SciencesWarsaw 00-818Poland

The typical mammalian neck consisting of seven cervical vertebrae(C1–C7)was established by the Late Permian in the cynodont forerunners of modern *** structure is precisely adapted to facilitate movements of the head during feeding,locomotion,predator evasion,and social ***,the clade including crown placentals,has a fossil record extending back more than 125 million years revealing significant morphological diversification in the *** very little is known concerning the early evolution of eutherian cervical morphology and its functional adaptations.A specimen of Zalambdalestes lechei from the Late Cretaceous of Mongolia boasts exceptional preservation of an almost complete series of cervical vertebrae(C2–C7)revealing a highly modified axis(C2).The significance of this cervical morphology is explored utilizing an integrated approach combining comparative anatomical examination across mammals,muscle reconstruction,geometric morphometrics and virtual range of motion *** compared the shape of the axis in Zalambdalestes to a dataset of 88 mammalian species(monotremes,marsupials,and placentals)using three-dimensional landmark *** results indicate that the unique axis morphology of Zalambdalestes has no close analog among living *** range of motion analysis of the neck strongly implies Zalambdalestes was capable of exerting very forceful head movements and had a high degree of ventral flexion for an animal its *** findings reveal unexpected complexity in the early evolution of the eutherian cervical morphology and suggest a feeding behavior similar to insectivores specialized in vermivory and defensive behaviors in Zalambdalestes akin to modern spiniferous mammals.

关键词： Atlas Axis Vertebral column Stem placental Morphology paleoecology

Pervasive Attentive Neural Network for Intelligent Image Classification Based on N-CDE’s

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Computers, Materials & Continua 2024年第4期79卷 1137-1156页

作者： Anas w.Abulfaraj Department of Information Systems Faculty of Computing and Information TechnologyKing Abdulaziz UniversityRabigh21911Saudi Arabia

The utilization of visual attention enhances the performance of image classification *** attentionbased models have demonstrated notable performance,but many of these models exhibit reduced accuracy when confronted with inter-class and intra-class similarities and ***-Controlled Differential Equations(N-CDE’s)and Neural Ordinary Differential Equations(NODE’s)are extensively utilized within this ***’s possesses the capacity to effectively illustrate both inter-class and intra-class similarities and differences with enhanced *** this end,an attentive neural network has been proposed to generate attention maps,which uses two different types of N-CDE’s,one for adopting hidden layers and the other to generate attention *** distinct attention techniques are implemented including time-wise attention,also referred to as bottom N-CDE’s;and element-wise attention,called topN-CDE’***,a trainingmethodology is proposed to guarantee that the training problem is sufficiently *** classification tasks including fine-grained visual classification andmulti-label classification,are utilized to evaluate the *** proposedmethodology is employed on five publicly available datasets,including CUB-200-2011,ImageNet-1K,PASCAL VOC 2007,PASCAL VOC 2012,and MS *** obtained visualizations have demonstrated that N-CDE’s are better appropriate for attention-based activities in comparison to conventional NODE’s.

关键词： Differential equations neural-controlled DE image classification attention maps N-CDE’s

The quasi-Gramian solution of a non-commutative extension of the higher-order nonlinear Schr?dinger equation

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Communications in Theoretical Physics 2024年第3期76卷 51-61页

作者： H w A Riaz J Lin Department of Physics Zhejiang Normal UniversityJinhua 321004China

The nonlinear Schr?dinger(NLS)equation,which incorporates higher-order dispersive terms,is widely employed in the theoretical analysis of various physical *** this study,we explore the non-commutative extension of the higher-order NLS *** treat real or complex-valued functions,such as g_(1)=g_(1)(x,t)and g_(2)=g_(2)(x,t)as non-commutative,and employ the Lax pair associated with the evolution equation,as in the commutation *** derive the quasi-Gramian solution of the system by employing a binary Darboux *** soliton solutions are presented explicitly within the framework of *** visually understand the dynamics and solutions in the given example,we also provide simulations illustrating the associated ***,the solution can be used to study the stability of plane waves and to understand the generation of periodic patterns within the context of modulational instability.

关键词： integrable systems Darboux transformation solitons

Recent Advances in the Synthesis and Polymerization of New CO_(2)-Based Cyclic

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Chinese Journal of Chemistry 2024年第4期42卷 430-443页

作者： Matteo Lanzi Arjan w.Kleij Institute of Chemical Research of Catalonia(ICIQ) The Barcelona Institute of Science and Technology(BIST)Av.Països Catalans 1643007 TarragonaSpain Catalan Institute of Research and Advanced Studies(ICREA) Pg.Lluís Companys 2308010 BarcelonaSpain

Carbon dioxide can be converted into functional heterocycles known as cyclic carbonates,whose recent reactivity has been expanded towards the formation of tailor-made engineering *** minireview gives an overview of the most topical developments in this area with a special focus on the synthetic methods employed to prepare these CO_(2)based *** addition,their application potential in the area of polymer science using a variety of polymerization techniques is discussed that have in common the ring-opening of the carbonate *** perspectives are provided that provide impetus for the scientific communities aligning research to the use of sustainable processes for polymers from recyclable carbon sources such as CO_(2).

关键词： Carbon dioxide Cyclic carbonates Functional macromolecules Heterocycles Polycarbonates Recycling Ring opening polymerization