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International Journal of Sediment Research 2021年第6期36卷 736-746页

作者： Sylvain Orseau Nicolas Huybrechts Pablo Tassi Damien Pham Van Bang Fabrice klein Cerema Direction Technique Eau Mer et Fleuves Sorbonne Universités Université de Technologie de Compiégne CNRSFRE2012 RobervalCentre de Recherche Royallieu Electricité de France R&D Department Laboratoire d'Hydraulique Saint Venant (ENPC-EDF/R&D-CEREMA) 5. Centre Eau Terre et Environnement INRS-ETE 6. Grand Port Maritime de Bordeaux

In order to optimize ship navigation in the macrotidal Gironde Estuary, a recent project funded by the port of Bordeaux aims at better understand and forecast hydrodynamic and fine sediment transport within the estuary. In the framework of this project, a two-dimensional hydro-sedimentary model is built. The model includes hydrodynamic forcings, mixed-sediment transport, and consolidation processes. The harmonic analysis of the astronomical tides reveals a strong distortion of the tidal wave inducing the growth of overtide constituents and the non-significant effect of tide-surge interactions in annual-scale prediction. Depending on hydrological conditions, river discharge can considerably alter the model accuracy due to the migration of the turbidity maximum zone modifying the bottom *** with measurements shows the ability of the model to reproduce suspended-sediment concentrations in the central Estuary. Sensitivity of the model to sediment features has also been discussed in regard of suspended-sediment concentrations and fluid mud deposits. The model will be further coupled with ship squat predictions and a morphodynamic model.

关键词： Sediment transport Numerical modeling Mixed sediment Gironde Estuary Opentelemac

Tetraphenylethylene-BODIPY aggregation-induced emission luminogens for near-infrared polymer light-emitting diodes

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Science China Chemistry 2018年第8期61卷 932-939页

作者： Sebnem Baysec Alessandro Minotto Patrick klein Simone Poddi Andrea Zampetti Sybille Allard Franco Cacialli Ullrich Scherf Macromolecular Chemistry and Institute for Polymer Technology Bergische Universitat Wuppertal Wuppertal 42097 Germany Department of Physics and Astronomy and London Centre for Nanotechnology University College London London WCIE 6BT UK

The aggregation-induced emission(AIE) phenomenon provides a new direction for the development of organic light-emitting devices. Here, we present a new class of emitters based on 4,4-difluoro-4-bora-3 a,4 a-diaza-s-indacene(BODIPY), functionalized at different positions with tetraphenylethylene(TPE), which is one of the most famous AIE luminogens. Thanks to this modification, we were able to tune the photoluminescence of the BODIPY moiety from the green to the near-infrared(NIR)spectral range and achieve PL efficiencies of ~50% in the solid state. Remarkably, we observed an enhancement of the AIE and up to ~100% photoluminescence efficiencies by blending the TPE-substituted BODIPY fluorophores with a poly[(9,9-di-noctylfluorene-2,7-diyl)-alt-(benzo[2,1,3]thiadiazol-4,7-diyl)](F8 BT) matrix. By incorporating these blends in organic lightemitting diodes(OLEDs), we obtained electroluminescence peaked in the range 650–700 nm with up to 1.8% external quantum efficiency and ~2 m W/cm2 radiance, a remarkable result for red/NIR emitting and solution-processed OLEDs.

关键词： BODIPY organic light-emitting diode aggregation-induced emission NIR emission photoluminescence electro luminescence

Tribological behaviour of sintered iron based self-lubricating composites

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Friction 2017年第3期5卷 285-307页

作者： Jose Daniel Biasoli DE MELLO Cristiano BINDER Gisele HAMMES Roberto BINDER Aloisio Nelmo klein Laboratorio de Materiais(LabMat) Universidade Federal de Santa Catarina Florianópolis 88.040-900 SC BrazilLaboratorio de Tribologia e Materiais Universidade Federal de Uberl(a)ndia Uberl(a)ndia 38.400-902 MG Brazil Laboratorio de Materiais(LabMat) Universidade Federal de Santa Catarina Florianópolis 88.040-900 SC Brazil Whirlpool Embraco Unit Joinville 89.219-900 SC Brazil

This work is a review of previous works,presenting and discussing the most important results obtained by an ongoing research program towards the development of innovative,low-cost,self-lubricating composites with a low friction coefficient and high mechanical strength and wear *** emphasis is given to uniaxial die pressing of solid lubricant particles mixed with matrix powders and to metal injection moulding associated with in situ generation of solid lubricant ***,a microstructural model/processing route (powder injection moulding followed by plasma-assisted debinding and sintering) produced a homogeneous dispersion of in situ generated solid lubricant *** nodules of graphite with diameter smaller than 20 μm were formed,constituting a nanostructured stacking of graphite foils with nanometric *** Raman analysis indicated that the graphite nodules were composed of turbostratic 2D graphite having highly misaligned graphene planes separated by large interlamellae *** interplanar distance between the graphene foils and misalignment of these foils were confirmed by transmission electron microscopy and were,probably,the origin of the outstandingly low dry friction coefficient (0.04).The effect of sintering temperature,precursor content,metallic matrix composition and surface finish is also ***,the influence of a double-pressing/double-sintering (DPDS) technique on the tribological performance of self-lubricating uniaxially die-pressed hBN + graphite-Fe-Si-C-Mo composite is also ***,the tribological behaviour of die-pressed Fe-Si-C matrix composites containing 5,7.5 and 10 wt％ solid lubricants (hBN and graphite) added during the mixing step is analysed in terms of mechanical properties and wear ***,the synergy between solid lubricant particles dispersed in a metallic matrix and fluid lubricants in a cooperative mixed lubrication regime is presented.

关键词： tribological behaviour powder metallurgy iron based self-lubricating composites turbostratic graphite

Solution of Partial Derivative Equations of Poisson and klein-Gordon with Neumann Conditions as a Generalized Problem of Two-Dimensional Moments

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Journal of Applied Mathematics and Physics 2020年第8期8卷 1606-1614页

作者： maria B. Pintarelli Department of Basic Sciences Faculty of Engineering National University of La Plata La Plata Argentina Mathematics Department Faculty of Exact Sciences National University of La Plata La Plata Argentina

It will be shown that finding solutions from the Poisson and klein-Gordon equations under Neumann conditions are equivalent to solving an integral equation, which can be treated as a generalized two-dimensional moment problem over a domain that is considered rectangular. The method consists to solve the integral equation numerically using the two-dimensional inverse moments problem techniques. We illustrate the different cases with examples.

关键词： Equation in Poisson Partial Derivatives klein-Gordon Equation Integral Equations Generalized Moment Problem

On Locating Malicious Code in Piggybacked Android Apps

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Journal of Computer Science & Technology 2017年第6期32卷 1108-1124页

作者： Li Li Daoyuan Li Tegawende F. Bissyande Jacques klein Haipeng Cai David Lo Yves Le Traon Interdisciplinary Centre for Security Reliability and Trust University of Luxembourg Luxembourg 2721 Luxembourg School of Electrical Engineering and Computer Science Washington State University Washington WA 99163 U.S.A. School of Information Systems Singapore Management University Singapore 178902 Singapore

To devise efficient approaches and tools for detecting malicious packages in the Android ecosystem, researchers are increasingly required to have a deep understanding of malware. There is thus a need to provide a framework for dissecting malware and locating malicious program fragments within app code in order to build a comprehensive dataset of malicious samples. Towards addressing this need, we propose in this work a tool-based approach called HookRanker, which provides ranked lists of potentially malicious packages based on the way malware behaviour code is triggered. With experiments on a ground truth of piggybacked apps, we are able to automatically locate the malicious packages from piggybacked Android apps with an accuracy@5 of 83.6% for such packages that are triggered through method invocations and an accuracy@5 of 82.2% for such packages that are triggered independently.

关键词： Android piggybacked app malicious code HookRanker

Ageism: Millennial Persistence

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Advances in Aging Research 2024年第1期13卷 1-14页

作者： Alejandro klein Oxford Institute of Population Ageing University of Guanajuato Leon Mexico

This work develops the idea that is possible to affirm that beyond its nuances. Ageism has shown a surprising force of prevalence in western society. Nourished by mythical, empirical, ideological and health elements, it has been enormously successful in imposing an image of vulnerability, decrepitude and illness on older adults. Since 1969, when the first academic article on the subject was published, much has been written on the subject, but little progress has been made in terms of social and state policies and community awareness. When an attempt has been made to propose an alternative to decrepit (Aristotelian as we suggest in this paper) ageism, nothing has emerged but a new kind of ageism that has imposed the supposed need that the older adult “must” be “productive”, “young”, “vigorous”, posing the impossibility, in short, once again, of the older adult living spontaneously as an older adult.

关键词： Ageism Stereotypes Prejudices

The New Social and Identitary Models of Old People—Deepening the Concept of Successful Ageing

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Advances in Aging Research 2022年第4期11卷 91-97页

作者： Alejandro klein Oxford Institute of Population Ageing University of Guanajuato Guanajuato Mexico

The concept of ageing society includes the quantitative factor that there will be more and more older people according to population transitions. But, at the same time, qualitative factors such as quality of life, identity changes and the experience of high changes in the subjectivity need to be included alongside these quantitative factors. So, the purpose and significance of the paper indicate that is necessary to ensure structures that can tolerate the new scenarios of this current generation of older people, who seek new life options, renewed emotional perspectives and transgenerational confrontation with traditional models of ageing and grandparenthood.

关键词： Old People Subjectivity Experimentation Identity Quality

Prognostic factors in patients hospitalized with acute heart failure syndrome

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Journal of Geriatric Cardiology 2006年第4期3卷 199-209页

作者： Liviu klein John B.O’Connell Division of Cardiology Center for Heart Failure Northwestern University Feinberg School of MedicineChicagoIL 60611USA

Each year, there are over one million hospitalizations for acute heart failure syndrome (AHFS) in the United States alone,with a similar number in Western Europe. These patients have very high short-term (2-6 months) mortality and readmission rates, while the healthcare system incurs substantial costs. Until recently, the clinical characteristics, management patterns, and outcomes of these patients have been poorly understood and, in consequence, risk stratification for these patients has not been well defined. Several risk prediction models that can accurately identify high-risk patients have been developed in the last year using data from clinical trials, large registries or administrative databases. Use of multi-variable risk models at the time of hospital admission or discharge offers better risk stratification and should be encouraged, as it allows for appropriate allocation of existing resources and development of clinical trials testing new treatment strategies for patients admitted with AHFS. The emerging observation that the prognosis for the ensuing three to six months may be obtained at presentation for AHFS has major implications for development of future therapies.

关键词： heart failure hospitalization risk factors prognosis

Theropod assemblages and a new ichnotaxon Gigandipus chiappei *** the Jiaguan Formation,Lower Cretaceous of Guizhou Province,China

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Geoscience Frontiers 2018年第6期9卷 1745-1754页

作者： Lida Xing Martin G.Lockley Hendrik klein Rong Zeng Sifu Cai Xiuchun Luo Chen Li State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesBeijing 100083China School of the Earth Sciences and Resources China University of GeosciencesBeijing 100083China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China Dinosaur Tracks Museum University of Colorado DenverPO Box 173364DenverCO 80217USA Saurierwelt Palantologisches Museum Alte Richt 7D-92318 NeumarktGermany Guizhou Provincial Museum Guiyang 550001China

A newly discovered Jiaguan Formation(Lower Cretaceous) tracksite from the Linjiang region of Guizhou Province, China, reveals the first example of a Cretaceous track morphotype attributable to the non-avian theropod ichnogenus Gigandipus, here named Gigandipus chiappei ichnosp nov. The theropod dominated locality also reveals the second report of the avian theropod ichnogenus Wupus, one of the largest avian traces currently known from the Lower Cretaceous. The Linjiang site provides evidence to support previous interpretations of a distinctive Lower Cretaceous theropod-dominated ichnofauna that was widespread in China and East Asia and highlights the similarity between Lower Cretaceous theropod ichnotaxa in East Asia and those found in the Lower Jurassic both in East Asia and elsewhere. These similarities in turn create various ichnotaxonomic challenges familiar to researchers working on theropod tracks, and we recommend caution in the naming of new theropod ichnotaxa at the ichnogenus level.

关键词： Early Cretaceous Jiaguan formation Theropod tracks Gigandipus Wupus

Early Jurassic basal sauropodomorpha dominated tracks from Guizhou, China: Morphology, ethology, and paleoenvironment

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Geoscience Frontiers 2019年第1期10卷 229-240页

作者： Lida Xing Martin G. Lockley Dongjie Tang Hendrik klein Guangzhao Peng Yong Ye Baoqiao Hao State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences School of Earth Sciences and Resources China University of Geosciences State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Dinosaur Trackers Research Group CB 172 University of Colorado at Denver Saurierwelt Pal?ontologisches Museum Zigong Dinosaur Museum

The newly discovered large(350 m^2) Yantan dinosaur tracksite, in the Lower Jurassic Ziliujing Formation of Guizhou Province, China, reveals at least 250 footprints of which ~97 can be resolved into trackways of sauropodomorphs. All the trackways are sub parallel likely indicating gregarious behavior. One theropod track(cf. Grallator) was recorded. The sauropodomorph tracks predominantly represent quadrupedal progression(Morphotype A), and footprint morphology is similar to the ichnospecies Liujianpusshunan, characterized by outward pes rotation. Three trackways indicate bipedal progression, and two of these(Morphotype B) indicate inward pes rotation, accompanied by elongate pes digit scratch marks. For the latter phenomenon three possible scenarios are discussed:(1) significant rotation changes accompanying changes in gait,(2) swimming behavior,(3) formation of *** evidence indicates the tracks were made on a linguloid rippled, muddy, immature sandstone substrate characterized by significant differences in substrate consistency across the trackbearing surface. Microbially induced sedimentary structures(MISS) characterized by distinctive wrinkle marks indicate a stressed, probably semi-arid, paleoenvironment that was not conducive to habitation by invertebrate organisms. This is consistent with other evidence that Lower Jurassic sauropodomorph tracks are often associated with semi-arid paleoenvironments.

关键词： Sauropodomorph tracks Ziliujing formation Lower Jurassic Guizhou Province