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Dynamic impact protective body armour:A comprehensive appraisal on panel engineering design and its prospective materials

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Defence Technology（防务技术） 2021年第6期17卷 2027-2049页

作者： Mulat Alubel Abtew françois Boussu Pascal Bruniaux Universite of Lille ENSAITGEMTEX Lab2 Allee Louise et Victor Champier59056RoubaixFrance Bahir Dar University Ethiopian Institute of Textile and Fashion TechnologyBahir DarEthiopia

Personal body armour is one of the most important pieces of equipment to protect human beings from various critical and fatal *** today’s modern world,various organizations including law enforcement and security service have made it mandatory for their personnel to wear personal protection system while on field ***,the systems should comprise an improved ballistic performance,light-weighted,flexible as well as comfortable panel not only to be accepted with a wider range but also for effective performances of the ***,the overall performances of the protective body armour could be affected by various parameters including armour design techniques,type of materials used and finishing of the *** current paper aims to critically review state-of-art for armour panel design techniques and the different perspective body armour *** paper starts by discussing the different body armour and its ***,the different states of technology for armour panel design(mostly for women),its problems and the possible solutions will be ***,the commonly used different polymeric fibrous and the future possible advanced materials including carbon nanotube(CNT),Graphene CNT and shear thickening fluids(STFs)treated materials for developing the reinforced body armour panel will be *** authors believe that this paper will enlighten useful guidelines and procedures about the different panel design techniques and current and promising future materials for researchers,designers,engineers and manufacturers working on the impact resistance body armour field.

关键词： Body armour panel design Ballistic impact behaviours Nanocomposites Shear thickening fluids(STFs) Military

Describing failure in geomaterials using second-order work approach

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Water Science and Engineering 2015年第2期8卷 89-95页

作者： franois Nicot Félix Darve Institut de Recherche en Sciences et Technologies de l'Environnement et de l'Agriculture(IRSTEA) Erosion Torrentielle Neige et Avalanches (ETNA)Geomechanics GroupGrenoble 38402 France Université Joseph Fourier (UJF)-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS) Laboratoire SolsSolides Structures et RisquesGrenoble 38041 France

Geomaterials are known to be non-associated materials. Granular soils therefore exhibit a variety of failure modes, with diffuse or localized kinematical patterns. In fact, the notion of failure itself can be confusing with regard to granular soils, because it is not associated with an obvious phenomenology. In this study, we built a proper framework, using the second-order work theory, to describe some failure modes in geomaterials based on energy conservation. The occurrence of failure is defined by an abrupt increase in kinetic energy. The increase in kinetic energy from an equilibrium state, under incremental loading, is shown to be equal to the difference between the external second-order work,involving the external loading parameters, and the internal second-order work, involving the constitutive properties of the material. When a stress limit state is reached, a certain stress component passes through a maximum value and then may decrease. Under such a condition, if a certain additional external loading is applied, the system fails, sharply increasing the strain rate. The internal stress is no longer able to balance the external stress, leading to a dynamic response of the specimen. As an illustration, the theoretical framework was applied to the well-known undrained triaxial test for loose soils. The influence of the loading control mode was clearly highlighted. It is shown that the plastic limit theory appears to be a particular case of this more general second-order work theory. When the plastic limit condition is met, the internal second-order work is nil. A class of incremental external loadings causes the kinetic energy to increase dramatically, leading to the sudden collapse of the specimen, as observed in laboratory.

关键词： Failure in geomaterials Undrained triaxial loading path Second-order work Kinetic energy Plastic limit condition Control parameter

Genesis of Daba arcuate structural belt related to adjacent basement upheavals:Constraints from Fission-track and (U-Th)/He thermochronology

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Science China Earth Sciences 2010年第11期53卷 1634-1646页

作者： GUILLOT franois Lab.FRE 3298 CNRS (Géosystèmes) Université Lille Nord de France

Fission-track, (U-Th)/He thermochronology, and cooling properties indicate that the southern Daba arcuate zone (SDBAZ) underwent a distinctive phase of rapid cooling in 153-100 Ma at a rate of 1.44-1.90°C/Ma. This rapid uplifting strongly contrasts with (1) the previous, rapid foreland subsidence during Early to Middle Jurassic in response to late-orogenic compression from the Qinling belt, (2) the succeeding long, slow cooling phase and relative thermal stability that occurred during the 100-45 Ma period. This rapid cooling event in the SDBAZ parallels those experienced by two adjacent upheavals of Huangling (HLUZ) and Hannan-Micang (HMUZ), with cooling rates of 2.22-3.17°C/Ma for the HLUZ in 160-126 Ma, 4.91°C/Ma for the southern HMUZ in 150-125 Ma, as well as 2.11°C/Ma for the northern HMUZ in 150-105 Ma. Comparing thermal histories among the SDBAZ, the HLUZ, the HMUZ, and the Wudang metamorphic zone (WDMZ), we infer that the Daba arcuate structural belt formed in 153-100 Ma. The combined dating data support a correlation with a low-angle arcuate south-thrusting of the Qinling orogen triggered by northward convergence of the Yangtze Craton, contemporaneously encountering rigid basement obstructions from the HLUZ and the HMUZ, respectively. Both the SDBAZ and neighboring domains additionally underwent a comparatively fast cooling and uplift since about 45 Ma.

关键词： Fission-track (U-Th)/He Daba arcuate belt basement upheavals correlation

Using orbital sensitivity analysis to pinpoint the role of orbital interactions in thermoelectric power factor

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npj Computational Materials 2023年第1期9卷 937-945页

作者： Wenhao Zhang Jean-françois Halet Takao Mori WPI Center for Materials Nanoarchitectonics(MANA) National Institute for Materials ScienceTsukubaJapan Graduate School of Pure and Applied Sciences University of TsukubaTsukubaJapan CNRS-Saint-Gobain-NIMS Laboratory for Innovative Key Materials and Structures(LINK)National Institute for Materials ScienceTsukubaJapan

The modification of the electronic band structure is of critical importance for thermoelectric materials whose heat to electricity power generation is related to carrier effective mass and alignment of semiconductor band *** approach to optimize the electronic band structure is by modification of orbital interactions through doping or *** the current ab-initio quantum chemical calculations can help us to investigate orbital components of electronic bands,they reveal little information on the relative tunability of electronic states and transport properties with respect to orbital *** this work,we present a method,based on a symmetry-adapted tight-binding model and sensitivity analysis,that can pinpoint the role of orbital interactions in determining electronic band structure and transport *** an application,a systematic theoretical analysis is used to show how the power factor of PbTe can/cannot be improved by playing with interatomic orbital *** orbital interaction sensitivity analysis introduced in this work can easily be applied to other compounds or properties.

关键词： properties orbital symmetry

Behavioral and physiological flexibility are used by birds to manage energy and support investment in the early stages of reproduction

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Current Zoology 2010年第6期56卷 767-792页

作者： franois VZINA Katrina G. SALVANTE Département de Biologie chimie et géographieGroupe de recherche sur les environnements nordiques BORASUniversité du Québec à Rimouski Department of Biological Sciences Simon Fraser University

Interest in phenotypic flexibility has increased dramatically over the last decade, but flexibility during reproduction has received relatively little attention from avian scientists, despite its possible impact on fitness. Because most avian species maintain atrophied reproductive organs when not active, reproduction in birds requires major tissue remodeling in preparation for breeding. Females undergo rapid （days） recrudescence and regression of their reproductive organs at each breeding attempt, while males grow their organs ahead of time at a much slower rate （weeks） and may maintain them at maximal size throughout the breeding season. Reproduction is associated with significant metabolic costs. Egg production leads to a 22%-27% increase in resting metabolic rate （RMR） over non-reproductive values. This is partly due to the activity of the oviduct, an organ that may allow females to adjust reproductive investment by modulating egg size and quality. In males, gonadal recrudescence may lead to a 30% increase in RMR, but the data are inconsistent and general conclusions regarding energetic costs of reproduction in males will require more research. Recent studies on captive female zebra finches describe the impacts of these costs on daily energy budgets and highlight the strategies used by birds to maintain their investment in reproduction when energy is limited. Whenever possible, birds use behavioral flexibility as a first means of saving energy. Decreasing locomotor activity saves energy during challenges such as egg production or exposure to cold temperatures and is an efficient way to buffer variation in individual daily energy budgets. However, when behavioral flexibility is not possible, birds must rely on flexibility at the physiological level to meet energy demands. In zebra finches breeding in the cold, this results in a reduced pace of laying, likely due to down-regulation of both reproductive and non-reproductive function, allowing females to defend mini

关键词： Phenotypic plasticity Phenotypic flexibility BMR Energy budget Organ Egg size Physiological tradeoff Fitness

A Formal Passage From a System of Boltzmann Equations for Mixtures Towards a Vlasov-Euler System of Compressible Fluids

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Acta Mathematicae Applicatae Sinica 2019年第1期35卷 158-173页

作者： Laurent DESVILLETTES fran?ois GOLSE Valeria RICCI Université Paris Diderot Sorbonne Paris Cité Institut de Mathématiques de Jussieu-Paris Rive GaucheUMR CNRS 7586 CNRS Sorbonne Universités UPMC Univ CMLS Ecole polytechnique et CNRS Université Paris-Saclay Dipartimento di Matematica e Informatica Università degli Studi di Palermo

A formal asymptotics leading from a system of Boltzmann equations for mixtures towards either Vlasov-Navier-Stokes or Vlasov-Stokes equations of incompressible fluids was established by the same authors and Etienne Bernard in: A Derivation of the Vlasov-Navier-Stokes Model for Aerosol Flows from Kinetic Theory Commun. Math. Sci., 15: 1703–1741(2017) and A Derivation of the Vlasov-Stokes System for Aerosol Flows from the Kinetic Theory of Binary Gas Mixtures. KRM, 11: 43–69(2018). With the same starting point but with a different scaling, we establish here a formal asymptotics leading to the Vlasov-Euler system of compressible fluids. Explicit formulas for the coupling terms are obtained in two typical situations: for elastic hard spheres on one hand, and for collisions corresponding to the inelastic interaction with a macroscopic dust speck on the other hand.

关键词： Vlasov-Euler system Boltzmann equation Hydrodynamic limit Aerosols Sprays Gas mixture

SEPARATION OF SCALES IN ELASTICITY IMAGING:A NUMERICAL STUDY

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Journal of Computational Mathematics 2010年第3期28卷 354-370页

作者： Habib Ammari Pierre Garapon franois Jouve Institut Langevin Laboratoire Ondes et Acoustique Laboratoire J.L.Lions Universite Paris Ⅶ Laboratoire J.L.Lions Université Paris Ⅶ

In magnetic resonance elastography, one seeks to reconstruct the shear modulus from measurements of the displacement field in the whole body. In this paper, we present an optimization approach which solves the problem by simply minimizing a discrepancy functional. In order to recover a complex anomaly in a homogenous medium, we first observe that the information contained in the wavefield should be decomposed into two parts, a ＂near-field＂ part in the region around the anomaly and a ＂far-field＂ part in the region away from the anomaly. As will be justified both theoretically and numerically, separating these scales provides a local and precise reconstruction.

关键词： Elastography multi-scale imaging anomaly reconstruction.

Hype and hope of hepatic arterial infusion for colorectal cancer

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Hepatobiliary Surgery and Nutrition 2021年第2期10卷 235-237页

作者： françois Ghiringhelli Centre de Recherche INSERM LNC-UMR1231 DijonFrance University of Burgundy franche-Comté DijonFrance Department of Medical Oncology Centre Georges-François LeclercDijonFrance Cancer Biology Transfer Platform Centre Georges-François LeclercDijonFrance Genetic and Immunology Medical Institute DijonFrance

Contrary to most solid metastatic cancers,metastatic colorectal cancer could be cured by surgical removal of the metastasis in the context of lung or liver *** retrospective studies performed 20 years ago showed that surgery alone led to cure of the patient in about 35%of cases(1).To improve patient survival and to increase the cure rate,perioperative intravenous chemotherapy was *** a large EORTC trial among highly selected patients,perioperative FOLFOX regimen improved relapse-free survival with an absolute difference in 3-year PFS of 8.1%(28.1%in the surgery-only group vs.36.2%in the perioperative chemotherapy group)and there was a non-significant increase in overall survival(5-year overall survival was 51.2%in the perioperative chemotherapy group vs.47.8%in the surgery-only group)(2).Despite this somewhat disappointing result,perioperative FOLFOX regimen became the standard of care for the management of resectable colorectal liver metastasis.

关键词： colorectal chemotherapy metastasis

Experimental and Numerical Analysis of a PCM-Integrated Roof for Higher Thermal Performance of Buildings

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Journal of Thermal Science 2024年第2期33卷 522-536页

作者： SIMON françois RUIZ-VALERO Letzai GIRARD Aymeric GALLEGUILLOS Hector Centro de Desarrollo Urbano Sustentable(CEDEUS) Pontificia Universidad Católica de Chile7500000SantiagoChile Facultad de Ciencias e Ingeniería Pontificia Universidad Católica Madre y Maestra(PUCMM)10103Santo DomingoDominican Republic LMGC IMT Mines AlesUniv MontpellierCNRS30100AlèsFrance Facultad de Ingeniería y Ciencias Universidad Adolfo Ibañez2520000Viña del MarChile Centro de Desarrollo Energético Antofagasta(CDEA) Universidad de Antofagasta1240000AntofagastaChile

Phase change materials(PCMs) designate materials able to store latent *** change state from solid to liquid over a defined temperature *** process is reversible and can be used for thermo-technical *** present paper aims to study the thermal performance of an inorganic eutectic PCM integrated into the rooftop slab of a test room and analyze its potential for building thermal *** experiment is conducted in two test rooms in Antofagasta(Chile) during summer,fall,and *** PCM is integrated into the rooftop of the first test room,while the roof panel of the second room is a sealed air *** work introduces a numerical model,which is built using the finite difference method and used to simulate the rooms' thermal *** thermal simulations of the PCM room are performed for other Chilean locations to evaluate and compare the capability of the PCM panel to store latent heat thermal energy in different *** show that the indoor temperature of the PCM room in Antofagasta varies only 21.1℃±10.6℃,while the one of the air-panel room varies 28.3℃±18.5℃.Under the experiment's conditions,the PCM room's indoor temperature observes smoother diurnal fluctuations,with lower maximum and higher minimum indoor temperatures than that of the air-panel *** simulations in other cities show that the PCM panel has a better thermal performance during winter,as it helps to maintain or increase the room temperature by some degrees to reach comfort *** demonstrates that the implementation of such PCM in the building envelope can effectively reduce space heating and cooling needs,and improve indoor thermal comfort in different climates of Chile.

关键词： phase change material thermal energy storage building space heating and cooling energy efficiency designbuilder