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A model-based prognostics method for fatigue crack growth in fuselage panels

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Chinese Journal of Aeronautics 2019年第2期32卷 396-408页

作者： Yiwei WANG christian GOGU Nicolas BINAUD christian BES Jian FU School of Mechanical Engineering and Automation Beihang University Institut Clément Ader (UMR CNRS 5312) INSA/UPS/ISAE/Mines Albi Université de Toulouse

This paper proposes a model-based prognostics method that couples the Extended Kalman Filter(EKF) and a new developed linearization method. The proposed prognostics method is developed in the context of fatigue crack propagation in fuselage panels where the model parameters are unknown and the crack propagation is affected by different types of uncertainties. The coupled method is composed of two steps. The first step employs EKF to estimate the unknown model parameters and the current damage state. In the second step, the proposed efficient linearization method is applied to compute analytically the statistical distribution of the damage evolution path in some future time. A numerical case study is implemented to evaluate the performance of the proposed method. The results show that the coupled EKF-linearization method provides satisfactory results: the EKF algorithm well identifies the model parameters, and the linearization method gives comparable prediction results to Monte Carlo(MC) method while leading to very significant computational cost saving. The proposed prognostics method for fatigue crack growth can be used for developing predictive maintenance strategy for an aircraft fleet, in which case, the computational cost saving is significantly meaningful.

关键词： Aircraft fuselage panels Extended Kalman filter Fatigue crack propagation Linearization method Model-based prognostics

Understanding Genetic Load in Potato for Hybrid Diploid Breeding

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Molecular Plant 2019年第7期12卷 896-898页

作者： christian W.B.Bachem Herman J.van Eck Michiel E.de Vries Plant Breeding Wageningen University and Research Wageningen the Netherlands Solynta Wageningen the Netherlands

Recently, Zhang et al.(2019) have managed to provide abundant evidence to support long-held theories regarding mechanisms of inbreeding depression and potential effects of heterosis that are likely to have a considerable impact on potato breeding in the future (Figure 1). despite its large genetic variation regarding yield, harvest index, and water use efficiency, potato breeding has attained only negligible advances in the most important breeding goals such as yield, tuber quality, and abiotic stress tolerance, and only modest progress in pathogen resistance. This low level of improvement is clearly due to the complexity of breeding a heterozygous tetraploid outbreeder rather than to the lack of genetic potential available in wild and cultivated material. In contrast, breeding at the diploid level, in particular in combination with self-compatibility, will allow the fixation of beneficial alleles to homozygosity.

关键词： Genetic Load Potato Hybrid Diploid Breeding

Phosphorus recovery from municipal and fertilizer wastewater:China's potential and perspective

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Journal of Environmental Sciences 2017年第2期29卷 151-159页

作者： Kuangxin Zhou Matthias Barjenbruch christian Kabbe Goulven Inial christian Remy Berlin Centre of Competence for Water Berlin 10709Germany department of Urban Water Management Technical University of BerlinBerlin 13355Germany Research&Innovation Asia Veolia EnvironmentBeijing 10004China

Phosphorus（P） is a limited resource, which can neither be synthesized nor substituted in its essential functions as nutrient. Currently explored and economically feasible global reserves may be depleted within generations. China is the largest phosphate fertilizer producing and consuming country in the world. China’s municipal wastewater contains up to 293,163 Mg year of phosphorus, which equals approximately 5.5% of the chemical fertilizer phosphorus consumed in China. Phosphorus in wastewater can be seen not only as a source of pollution to be reduced, but also as a limited resource to be recovered. Based upon existing phosphorus-recovery technologies and the current wastewater infrastructure in China, three options for phosphorus recovery from sewage sludge, sludge ash and the fertilizer industry were analyzed according to the specific conditions in China.

关键词： Phosphorus recovery Municipal Wastewater Fertilizer Industry Sewage sludge China

Robot Off-Line Programming for Thermal Spraying

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稀有金属材料与工程 2012年第S1期41卷 13-17页

作者： christian Coddet Laboratoire d'Etudes et de Recherches sur les Matériaux les Procédés et les Surfaces(LERMPS)Université de Technologie de Belfort-Montbéliard(UTBM)Belfort Cedex 90010French

The purpose of this study is to introduce the current applications of off-line programming technology in thermal spraying,including some popular methods of path generation,procedure simulation,robot kinematics optimization,*** this technology reduces the difficulty of robot programming and enormously improves its facility for thermal *** the last part of this paper,presented two examples of off-line programming in thermal spraying which refer to trajectory optimization on a work piece with a great angle and path generation on the complex work *** simulations and experiments have proved that off-line programming can effectively improve the production efficiency and the quality of coating.

关键词： off-line programming toolkit thermal spraying trajectory optimization

Probabilistic approach for open pit bench slope stability analysis——A mine case study

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International Journal of Mining Science and Technology 2019年第4期29卷 629-640页

作者： christian Obregon Hani Mitri department of Mining and Materials Engineering McGill University

The geotechnical slope design of an open pit wall starts at the bench scale *** this scale,the rock slope stability is governed primarily by the geological discontinuities within the rock mass and as a result,structurally-controlled failures(***,wedge or toppling)are most likely to *** probabilistic approach offers a major advantage over the traditional deterministic method in that it accounts for the different degrees of variability and uncertainty often encountered in rock *** paper presents a bench slope stability assessment for an open pit mine in Peru using a probabilistic-based approach by coupling a kinematic analysis based on stereographic projection techniques followed by a kinetic analysis by means of the limit equilibrium ***,these two probabilities are combined to provide an overall measure of the probability of failure(PoF)of the bench slope *** case study is characterized by significant scatter in the geometrical and mechanical properties of the *** surface mapping was conducted at 36 different sites following the ISRM suggested *** direct shear tests were carried *** is shown that by combining field and laboratory measurements and engineering judgment,the probability density functions(PDF)of the discontinuity parameters can be *** are then used in a Monte Carlo simulation process to compute both kinematic and kinetic probabilities of *** overall probability of failure aims to provide the design engineer with a tool to critically evaluate the bench performance from a geotechnical risk perspective and to provide a basis for future bench design optimization.

关键词： Mine safety Rock slope stability Kinematic analysis Probability of failure Limit equilibrium analysis Case study

design and calibration of a high-sensitivity and high-accuracy polarimeter based on liquid crystal variable retarders

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Research in Astronomy and Astrophysics 2017年第1期17卷 87-96页

作者： Jing Guo de-Qing Ren Cheng-Chao Liu Yong-Tian Zhu Jiang-Pei Dou Xi Zhang christian Beck National Astronomical Observatories/Nanjing Institute of Astronomical Optics & Technology Chinese Academy of Sciences Nanjing 210042 China Key Laboratory of Astronomical Optics & Technology Nanjing Institute of Astronomical Optics & TechnologyChinese Academy of Sciences Nanjing 210042 China Physics and Astronomy department California State University Northridge 18111 Nordhoff Street NorthridgeCalifornia 91330-8268 USA National Solar Observatory Boulder CO 80303 USA

Polarimetry plays an important role in the measurement of solar magnetic fields. We devel- oped a high-sensitivity and high-accuracy polarimeter （HHP） based on nematic liquid crystal variable retarders （LCVRs）, which has a compact setup and no mechanical moving parts. The system design and calibration methods are discussed in detail. The azimuth error of the transmission axis of the polarizer as well as the fast axes of the two LCVRs and the quarter-wave plate were determined using dedicated procedures. Linearly and circularly polarized light were employed to evaluate the performance of the HHP. The experimental results indicate that a polarimetric sensitivity of better than 5.7 × 10-3 can be achieved by using a single short-exposure image, while an accuracy on the order of 10-5 can be reached by using a large number of short-exposure images. This makes the HHP a high-performance system that can be used with a ground-based solar telescope for high-precision solar magnetic field investigations.

关键词： instrumentation polarimeters - methods laboratory - Sun magnetic fields - tech-niques polarimetric

TOLs Function as Ubiquitin Receptors in the Early Steps of the ESCRT Pathway in Higher Plants

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Molecular Plant 2020年第5期13卷 717-731页

作者： Jeanette Moulinier-Anzola Maximilian Schwihla Lucinda de-Araujo Christina Artner Lisa Jorg Nataliia Konstantinova christian Luschnig Barbara Korbei Institute of Molecular Plant Biology Department of Applied Genetics and Cell BiologyUniversity of Natural Resources and Life SciencesVienna(BOKU)Muthgasse 181190 ViennaAustria department of Molecular Toxicology and Environment Biotechnology Center-Eduardo Mondlane UniversityAv.de MocambiqueKm 1.5.MaputoMozambique Institute of Science and Technology Austria(1ST Austria) Am Campus 13400 KlosterneuburgAustria

Protein abundance and localization at the plasma membrane(PM)shapes plant development and mediates adaptation to changing environmental *** is regulated by ubiquitination,a post-translational modification crucial for the proper sorting of endocytosed PM proteins to the vacuole for subsequent *** understand the significance and the variety of roles played by this reversible modification,the function of ubiquitin receptors,which translate the ubiquitin signature into a cellular response,needs to be *** this study,we show that TOL(TOM1-like)proteins function in plants as multivalent ubiquitin receptors,governing ubiquitinated cargo delivery to the vacuole via the conserved Endosomal Sorting Complex Required for Transport(ESCRT)***2 and TOL6 interact with components of the ESCRT machinery and bind to K63-linked ubiquitin via two tandemly arranged conserved ubiquitin-binding *** of these domains results not only in a loss of ubiquitin binding but also altered localization,abolishing TOL6 ubiquitin receptor *** and localization of TOL6 is itself regulated by ubiquitination,whereby TOL6 ubiquitination potentially modulates degradation of PM-localized cargoes,assisting in the fine-tuning of the delicate interplay between protein recycling and *** together,our findings demonstrate the function and regulation of a ubiquitin receptor that mediates vacuolar degradation of PM proteins in higher plants.

关键词： ubiquitination ESCRT pathway ubiquitin receptor plasma membrane protein degradation

Experimental investigations of a full model with adaptive elasto-flexible membrane wings

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Chinese Journal of Aeronautics 2021年第7期34卷 211-218页

作者： Jonathan PFLU GER christian BREITSAMTER Chair of Aerodynamics and Fluid Mechanics Technical University of MunichGarching 85748Germany

The morphing wing concept aims to constantly adapt the aerodynamics to different flight *** wing is able to adapt to different flight conditions by an adjustable Aspect Ratio(AR)and sweep.A high AR configuration provides high aerodynamic efficiency,while a low AR configuration,with highly swept wings offers a good ***,the flexible membrane allows the wing surface to stretch and contract in-plane as well as the airfoil to adapt to different aerodynamic *** the context of this work,the aerodynamic characteristics of a full model with form-adaptive elasto-flexible membrane wings are investigated *** focus is on the high-lift regime and on the analysis of the aerodynamic coefficients as well as their ***,the lateral aerodynamic derivatives at asymmetric wing positions are of interest.

关键词： Experimental aerodynamics Flexible wing surface Force and moment measurements Morphing wing Particle image velocimetry

Block Copolymer-Templated BiFeO3 Nanoarchitectures Composed of Phase-Pure Crystallites Intermingled with a Continuous Mesoporosity： Effective Visible-Light Photocatalysts？

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Nano Research 2011年第4期4卷 414-424页

作者： christian Reitz christian Suchomski Christoph Weidmann Torsten Brezesinski Institute of Physical Chemistry Justus-Liebig-University Giessen Giessen 35392 Germany

Herein is reported the soft-templating synthesis of visible-light photoactive bismuth ferrite （BiFeO3） nanoarchitectures in the form of thin fihns using a poly（ethylene-co-butylene）-block-poly（ethylene oxide） diblock copolymer as the structure-directing agent. We establish that （1） the self-assembled materials employed in this work are highly crystalline after annealing at 550 ℃ in air and that （2） neither the bismuth-poor Bi2Fe4O9 phase nor other impurity phases are formed. We further show that there is a distinct restructuring of the high quality cubic pore network of amorphous BiFeO3 during crystallization. This restructuring leads to films with a unique architecture that is composed of anisotropic crystallites intermingled with a continuous mesoporosity. While this article focuses on the characterization of these novel materials by electron microscopy, krypton physisorption, grazing incidence small-angle X-ray scattering, time-of-flight secondary ion mass spectrometry, X-ray photoelectron spectroscopy, UV-vis and Raman spectroscopy, we also examine the photocatalytic properties and show the benefits of the combination of mesoporosity and nanocrystallinity. Templated BiFeO3 thin films （25% porosity） with a direct optical band gap at 2.9 eV exhibit a catalytic activity for the degradation of rhodamine B much better than that of nontemplated samples. We attribute this improvement to the nanoscale porosity, which provides for more available active sites on the photocatalyst.

关键词： Self-assembly mesoporous nanocrystalline thin films photocatalysis multiferroic