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Analysis of global momentum transfer due to buried mine detonation

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Defence Technology（防务技术） 2019年第5期15卷 821-827页

作者： N.heider V.Denefeld H.Aurich Ernst-Mach-Institute

The emergence of improvised explosive devices (IED) significantly extended the spectrum of possiblethreat mechanisms to military vehicles and their occupants. Especially buried high explosive (HE)charges lead to new and originally not investigated loading conditions during their detonation. It is theinteraction of the embedding geomaterial with the detonation products that leads to a strongly increasedglobal impulse transfer on the vehicle with following high accelerations on the vehicle occupant. Thispaper presents a comprehensive approach for the analysis of occupant loading. In a first step, we presentthe so called ring technology which allows the experimental determination of the locally resolvedspecific impulse distribution on a vehicle floor due to buried charge detonation. A complementarymethod is the use of scaled model vehicles that allows the determination of global vehicle loading parameterssuch as jump height or vehicle accelerations. Both techniques were used to study the influenceof burial conditions as burial depth, embedding material or water content on the impulse transfer ontothe vehicle. These experimental data are used to validate material models for the embedding sand orgravel materials. This validated material description is the basis for numerical simulation models used inthe assessment of occupant safety. In the last step, we present a simulation model for a generic militaryvehicle including a Hybrid III occupant dummy that is used for the determination of biomechanicaloccupant exposure levels. Typical occupant loadings are evaluated and correlated with burial conditionsas HE mass and global momentum transfer.

关键词： Improvised explosive device Vehicle protection Occupant loading

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

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

Effective-Spring Model of Tympanic Response in Archosaurs

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Open journal of Biophysics 2019年第1期9卷 21-50页

作者： David T. heider j. Leo van Hemmen Physik Department T35 and Department of Mathematics Technische Universit&auml t München München Germany

Whereas for smaller animals the eardrums are well-characterized as excitable membranes or drums, some animals such as several archosaurs feature, as a first approximation, a rather stiff elastic shell supported by an elastic ring. Mathematically, the theory of plates and shells is applicable but its governing equations overly complicate the modeling. Here the notion of tympanic structure is introduced as a generalization of “ordinary” tympanic membranes so as to account for sound perception as it occurs in archosaurs, such as birds and crocodilians. A mathematical model for the tympanic structure in many archosaurs called two-spring model implements this notion. The model is exactly soluble and solutions are presented in closed form and as a series expansion. Special emphasis is put onto offering an easy-to-apply model for describing experiments and performing numerical studies. The analytic treatment is supplemented by a discussion of the applicability of the two-spring model in auditory research. An elasticity-theoretic perspective of the two-spring model is given in the Appendix.

关键词： Two-Piece Eardrum Eardrum Vibrations Shell Elasticity Archosaurs

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

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网状玻璃碳液流电极的改进

南京农业大学学报 1986年第1期 105-107页

作者： G.H.heider,H.j.Weick,A.M.Yacynych,黄克明美国新泽西州立大学化学系美国新泽西州立大学化学系美国新泽西州立大学化学系南京农业大学无机化学教研组

网状玻璃碳(Reticulated Vitreous Carbon,下文简称R.V.C.)是1976年发展起来的一种新型碳材料。当时主要用在过滤、高温绝热等方面。由于它的多孔结构,以及它具有某些物理、化学、电化学方面的优良特性,Norvell和Mamantov于1977年首次... 详细信息

网状玻璃碳(Reticulated Vitreous Carbon,下文简称R.V.C.)是1976年发展起来的一种新型碳材料。当时主要用在过滤、高温绝热等方面。由于它的多孔结构,以及它具有某些物理、化学、电化学方面的优良特性,Norvell和Mamantov于1977年首次发表了关于用R.V.C.作为电极材料的论文。其后,每年都有一些对R.V.C.电极研究的报道。

关键词：电极材料转化率升/分 CN 玻璃碳饱和甘汞电极液流

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苏黎世——从保守的银行总部到时尚创意之都

国际城市规划 2012年第3期27卷 30-35页

作者：卡萨瑞娜.海德玛蒂娜.考-施耐森玛雅周勇德国多特蒙德大学空间规划学院欧洲规划文化系瑞士苏黎世联邦科技学院北京国城建筑设计公司

1凤凰涅槃：苏黎世在浴火中重生在32年前的那个夏天,苏黎世经历了一场变革之火的砺炼。1980年5月30日晚,在一场鲍勃·马利（Bob Marley）的演唱会结束后,苏黎世歌剧院门口聚集了数百名激进主义青年,他们抗议政府拨给苏黎世歌剧院的一笔... 详细信息

1凤凰涅槃：苏黎世在浴火中重生在32年前的那个夏天,苏黎世经历了一场变革之火的砺炼。1980年5月30日晚,在一场鲍勃·马利（Bob Marley）的演唱会结束后,苏黎世歌剧院门口聚集了数百名激进主义青年,他们抗议政府拨给苏黎世歌剧院的一笔高达6100万瑞士法郎的专项津贴。示威活动一直持续到第二天,这些年轻人还要求政府出资筹建真正属于他们自己的艺术中心——一个具有包容性的艺术交流场所——不仅可以承载那些长久以来统治着歌剧院和音乐厅等大雅之堂的主流艺术形式，更重要的是，也要为那些不起眼的非主流文化提供生存空间。抗议者最终将矛头指向了一个残酷的现实，即在这座城市中，总会有数以百万计的投资划给“主流艺术”，而那些“非主流艺术”却罕有人问津。

关键词：苏黎世艺术形式创意时尚银行保守歌剧院交流场所