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Engineering tool for the evaluation of global IED effects

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Defence Technology（防务技术） 2016年第2期12卷 214-221页

作者： n.heider v.denefeld a.steinbrenner a.holzwarth Ernst-Mach-Institute Eckerstr.479104 FreiburgGermany Ernst-Mach-Institute Am Christianswuhr 279400 KandernGermany

The detonation of an IED near a military vehicle induces different damage effects on the vehicle and its occupants. There are local effects from fragments and projectiles but there are also global effects from a momentum transfer on the complete vehicle structure and a subsequent dynamical motion of the vehicle with phenomena like overturning or vehicle displacement from the *** like this can be answered with numerical finite-element simulations but there is also the need for engineering tools that allow a quick and nearly instantaneous simulation of these phenomena. The following work presents an approach for a fast analysis of global IED effects on vehicles. The physical modelling is based on analytical formula and empirical data that describe the momentum transfer of a detonation on a nearby structure. This momentum is the initial condition for the calculation of the following vehicle motion and the simulation of vehicle dynamics and jump *** software itself has a modern GUI that allows the generation of the vehicle structure and the threat scenario together with an interactive analysis of the simulation *** engineering tool is validated with small size generic vehicle tests where jump height and the vehicle motion are compared. The software allows a detailed analysis of global IED effects and can be additionally used in an inverse mode for the analysis of incidents with the determination of used HE masses in an IED attack.

关键词： IED 工具工程军事车辆有限元模拟评价爆炸装置车辆结构

Reduction of global effects on vehicles after IED detonations

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Defence Technology（防务技术） 2014年第2期10卷 219-225页

作者： V.DEnEFELD n.heider A.HOLZWARTH A.SATTLER M.SALK Ernst-Mach-Institute Eckerstr.4 Ernst-Mach-Institute Am Christianswuhr 2

Global effects caused by the detonation of an IED near a military vehicle induce subsequent severe acceleration effects on the vehicle *** concepts to minimize these global effects were developed,with the help of a combined method based on a scaled experimental technology and numerical *** first concept consists in the optimization of the vehicle shape to reduce the momentum transfer and thus the occupant *** scaled V-shaped vehicles with different ground clearances were built and compared to a reference vehicle equipped with a flat *** second concept,called dynamic impulse compensation(DIC),is based on a momentum compensation *** principal possibility of this concept was demonstrated on a scaled *** addition,the numerical simulations have been performed with generic full size vehicles including dummy models,proving the capability of the DIC technology to reduce the occupant loading.

关键词：军用车辆 IED 爆炸数值模拟动量转移实验技术离地间隙动态补偿

Haplotype-based phylogenetic analysis and population genomics uncover the origin and domestication of sweetpotato

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Molecular Plant 2024年第2期17卷 277-296页

作者： Mengxiao Yan Ming Li Yunze Wang Xinyi Wang M-Hossein Moeinzadeh Dora G.Quispe-Huamanquispe Weijuan Fan Yijie Fang Yuqin Wang Haozhen nie Zhangying Wang Aiko Tanaka Bettina heider Jan F.Kreuze Godelieve Gheysen Hongxia Wang Martin Vingron Ralph Bock Jun Yang Shanghai Key Laboratory of Plant Functional Genomics and Resources Shanghai Chenshan Botanical GardenShanghai 201602China College of Life Sciences Chongqing Normal UniversityChongqing 401331China Biotechnology and nuclear Technology Research Institute Sichuan Academy of Agricultural SciencesChengdu 610061China College of Life Sciences Shanghai Normal UniversityShanghai 200234China Department of Computational Molecular Biology Max Planck Institute for Molecular GeneticsIhnestraBe 63-7314195 BerlinGermany Department of Biotechnology Ghent University9000 GhentBelgium Guangdong Provincial Key Laboratory of Crops Genetics and Improvement Crop Research InstituteGuangdong Academy of Agricultural SciencesGuangzhou 510640China Graduate School of Bioagricultural Sciences Nagoya UniversityChikusaNagoya 464-8601Japan international Potato Center(CIP) LimaPeru CAS Center for Excellence of Molecular Plant Sciences Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai 200233China Max-Planck-Institut fur Molekulare Pflanzenphysiologie Am Muhlenberg 114476 Potsdam-GolmGermany

The hexaploid sweetpotato(lpomoea batatas)is one of the most important root crops ***,its genetic origin remains controversial,and its domestication history remains *** this study,we used a range of genetic evidence and a newly developed haplotype-based phylogenetic analysis to identify two probable progenitors of *** diploid progenitor was likely closely related to lpomoea ae-quatoriensis and contributed the B,subgenome,IbT-DnA2,and the lineage 1 type of chloroplast genome to *** tetraploid progenitor of sweetpotato was most likely *** 4x,which donated the B2 subgenome,IbT-DnA1,and the lineage 2 type of chloroplast *** most likely originated from reciprocal crosses between the diploid and tetraploid progenitors,followed by a subsequent whole-genome *** addition,we detected biased gene exchanges between the subgenomes;the rate of B,to B2 subgenome conversions was nearly three times higher than that of B2 to B subgenome *** analyses revealed that genes involved in storage root formation,maintenance of genome stabil-ity,biotic resistance,sugar transport,and potassium uptake were selected during the speciation and domestication of *** study sheds light on the evolution of sweetpotato and paves the way forimprovementofthiscrop.

关键词： sweetpotato origin gene conversion domestication IbT-DnA HPA

Measurement of the spatial specific impulse distribution due to buried high explosive charge detonation

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Defence Technology（防务技术） 2017年第3期13卷 219-227页

作者： V. Denefeld n. heider A. Holzwarth Fraunhofer Institute for High-Speed Dynamics Ernst-Mach-Institut EMI Ernst-Mach-Institut

Buried high explosive(HE) charges represent a high threat to military vehicles. The detonation of these charges can lead to significant momentum transfer onto vehicles and their occupants. A detailed understanding of the physical processes involved in the loading of vehicle structures is necessary for an optimization of effective countermeasures and protection systems. A quantitative description of the local momentum distribution on the vehicle underbody due to the detonation process is of special importance. In the following, a new test setup is presented that allows the experimental determination of the specific impulse distribution. It is based on a ring arrangement where the elements are nested into each other and the velocity of each ring is correlated with the local specific impulse at its *** momentum transfer to a vehicle depends on a number of influencing factors such as: charge mass,embedding material(e.g. sand, gravel, clay), density, water content, saturation, depth of burial, ground clearance and vehicle shape. The presented technology is applied to quantify the influence of the embedding material(alluvial sand, quartz sand), the burial depth and the water content on the local specific impulse distribution. The obtained data can be used as initial condition for the numerical simulation of occupant safety assessment and as input for empirical modeling of momentum transfer on structures.

关键词：装药爆炸比冲军用车辆测量空间炸药车辆结构包埋材料

Analysis of global momentum transfer due to buried mine detonation

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