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乘用车前部造型的改变对行人下肢损伤的影响研究

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振动与冲击 2024年第9期43卷 291-297页

作者：王丙雨刘天泉韩勇 otte Dietmar 秦利燕李红厦门理工学院机械与汽车工程学院福建厦门361024 福建省客车及特种车辆研发协同创新中心福建厦门361024 福建省客车先进设计与制造重点实验室福建厦门361024 汉诺威医学院事故调查科德国汉诺威30625 国汽(北京)智能网联汽车研究院有限公司北京100029

研究了欧盟行人保护指令发布后车辆前部造型的变化,以及该变化对行人下肢损伤的影响。为此,在德国深度事故调查数据库选取了283起带有行人下肢损伤的事故案例,并将事故案例以欧洲行人保护指令发布时间为界限分为两组。首先采用描述性统... 详细信息

研究了欧盟行人保护指令发布后车辆前部造型的变化,以及该变化对行人下肢损伤的影响。为此,在德国深度事故调查数据库选取了283起带有行人下肢损伤的事故案例,并将事故案例以欧洲行人保护指令发布时间为界限分为两组。首先采用描述性统计方法统计了两组案例中各个事故车辆前部结构值,然后利用威尔科克森符号秩检验找出两组案例车型中具有显著差异的前部结构参数,最后通过二元逻辑回归分别建立两组案例车型与行人下肢严重损伤和腓骨/胫骨骨折风险曲线,分析行人保护指令发布后车辆前部造型的改变及对行人下肢损伤的影响。研究结果表明,新的车型具有更宽的前保险杠和更浅的保险杠伸出量,更高的引擎盖前缘以及更低的副保险杠下缘高度。在0~40 km/h的碰撞速度内,对于年龄不超过60岁的行人,行人保护指令发布后生产的车型对行人整体下肢严重损伤和腓骨/胫骨的保护性能相比于以往的车型均有所提高。

关键词：符号秩检验逻辑回归行人下肢损伤风险汽车前部结构参数

BRAIN INJURY BIOMECHANICS IN REAL WORLD VEHICLE ACCIDENT USING MATHEMATICAL MODELS

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Chinese Journal of Mechanical Engineering 2008年第4期21卷 81-86页

作者： YANG Jikuang XU Wei otte Dietmar State Key Laboratory of Advanced Design and Manufacture for Vehicle Body Hunan University Changsha 410082 China Accident Research Unit Medical University HannoverHannover D-30623 Germany

This paper aims at investigating brain injury mechanisms and predicting head injuries in real world accidents. For this purpose, a 3D human head finite element model （HBM-head） was developed based on head-brain anatomy. The HBM head model was validated with two experimental tests. Then the head finite element（FE） model and a multi-body system （MBS） model were used to carry out reconstructions of real world vehicle-pedestrian accidents and brain injuries. The MBS models were used for calculating the head impact conditions in vehicle impacts. The HBM-head model was used for calculating the injury related physical parameters, such as intracranial pressure, stress, and strain. The calculated intracranial pressure and strain distribution were correlated with the injury outcomes observed from accidents. It is shown that this model can predict the intracranial biomechanical response and calculate the injury related physical parameters. The head FE model has good biofidelity and will be a valuable tool for the study of injury mechanisms and the tolerance level of the brain.

关键词： Skull-brain FE model Head injury Real-world vehicle accident

High strength and ductility of titanium matrix composites by nanoscale design in selective laser melting

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Journal of Materials Science & Technology 2022年第23期118卷 114-127页

作者： Joseph A.otte Jin Zou Matthew S.Dargusch School of Mechanical and Mining Engineering The University of QueenslandBrisbaneQLD 4072Australia Center for Microscopy and Microanalysis The University of QueenslandBrisbaneQLD 4072Australia

The use of selective laser melting(SLM)to produce titanium matrix composites(TMCs)with high strength while retaining sufficient tensile ductility suitable for structural applications is emerging as an attractive opportunity in the field of advanced ***,the presence of coarse ceramic reinforcements as well as difficulties in optimizing the SLM process is a barrier to the application of *** this study,we demonstrated the production of TMCs reinforced with in situ high aspect ratio Ti B nanowhiskers by selective laser melting using nanosized BN powder *** Ti with 2.5 vol.%nanosized BN powder showed promise for producing high performance TMCs with retained *** acted to produce Ti B nanowhiskers with diameter<50 ***,by controlling post process furnace annealing Ti B retained a low diameter but exhibited a high aspect ratio,up to *** addition to Ti B refinement,nanosized BN addition promoted grain refinement during SLM,both acting as a solute to induce nucleation events and,as Ti B is formed,providing nucleation sites leading to an ultrafine grain structure in as printed samples and after *** produced TMCs exhibit high tensile yield strength,up to1392 MPa,while retaining tensile ductility up to 10%.This study has shown how nanoscale design in powder bed fusion additive manufacturing techniques can be used to produce high performance TMCs through a combination of refined grain structure and high aspect ratio Ti B leading to TMCs with significant improvement in strength,isotropic properties and retained tensile ductility.

关键词： Additive manufacturing Selective laser melting Metal matrix composite Mechanical properties Nanostructure Nanowires

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车辆与行人碰撞事故中下肢损伤风险研究

振动与冲击 2016年第23期35卷 1-5页

作者：王丙雨杨济匡 otte Dietmar 王方湖南大学汽车车身先进制造国家重点实验室长沙410082 查尔摩斯理工大学应用力学系瑞典哥德堡41296 汉诺威医科大学事故调查科德国汉诺威30625 厦门理工学院机械与汽车工程学院福建厦门361024

研究行人与车辆碰撞事故中下肢损伤风险,并确定碰撞速度和行人年龄、身高以及体重等损伤相关参数值在下肢轻微损伤组和严重损伤组之间的分布是否存在显著差异。为此,首先从德国深入事故研究数据库(GIDAS)中挑选出354个带有行人下肢损伤... 详细信息

研究行人与车辆碰撞事故中下肢损伤风险,并确定碰撞速度和行人年龄、身高以及体重等损伤相关参数值在下肢轻微损伤组和严重损伤组之间的分布是否存在显著差异。为此,首先从德国深入事故研究数据库(GIDAS)中挑选出354个带有行人下肢损伤的案例来进行单因素方差分析,接着利用逻辑回归分析方法建立行人下肢严重损伤风险函数模型,分析车辆碰撞速度和行人年龄、身高以及体重对行人下肢严重损伤风险的影响。分析结果表明:碰撞速度和行人年龄是影响行人下肢严重损伤的显著性因素,而体重与身高不是影响行人下肢严重损伤的显著性因素;并且行人下肢严重损伤风险与碰撞速度以及行人年龄正相关。当碰撞速度为43 km/h时,行人下肢严重损伤风险达到50%。

关键词：交通事故行人下肢严重损伤逻辑回归模型碰撞速度行人年龄

Distribution and effects of tree leaf litter on vegetation composition and biomass in a forest–grassland ecotone

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Journal of Plant Ecology 2014年第3期7卷 264-275页

作者： Alejandro Loydi Kerstin Lohse Annette otte Tobias W.Donath R.Lutz Eckstein Institute of Landscape Ecology and Resource Management Research Center for BiosystemsLand Use and Nutrition(IFZ)Justus-Liebig University GiessenHeinrich-Buff-Ring 26-32DE-35392GiessenGermany

Aims After abandonment of grasslands,secondary succession leads to the invasion by woody *** process begins with the accumulation of tree litter in the forest–grassland *** objectives were to determine the relationships between litter amounts and vegetation composition and cover along natural forest–grassland ecotones and to experimentally study the initial effects of tree litter accumulation on grassland vegetation and on microsite *** We established 11 transects varying from 12 to 15 m in length in different forest–grassland ecotones in the Lahn-Dill highlands,Germany,and measured the mass and cover of tree litter and the cover and composition of vegetation at five sequential positions along each transect by using 1 m2 plots with five *** a field experiment,we established plots subjected to different litter amounts(0,200 and 600g m^(−2))and evaluated changes in grassland vegetation,soil temperature and soil nutrient availability below the litter *** Findings Tree litter amounts decrease from 650 to 65g m^(−2) across the forest–grassland *** changed from shrubs and annual species(adapted to more stressful conditions)in the forests edge to grasses,rosettes and hemirosette species(with higher competitive abilities)in the *** anthropogenic forest–grassland ecotones showed abrupt edges,and the two adjacent ecosystems were characterized by different species pools and functional *** the field experiment,the presence of a litter layer reduced vegetation biomass and cover;the species richness was only reduced in the treatment with high litter(600g m^(−2)).Additionally,adding litter on top of vegetation also reduced thermal amplitude and the number of frost days,while increasing the availability of some nutrients,such as nitrogen and aluminium,the latter being an indicator of soil *** a tree litter layer of 600g m^(−2) in grassland areas had strong effects on the compos

关键词： forest edge land abandonment land use change litter oak(Quercus robur) semi-natural grassland tree invasion

车辆和自行车碰撞事故中骑车人下肢损伤风险研究

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振动与冲击 2023年第11期42卷 324-330页

作者：王丙雨邹俊韩勇 otte Dietmar 刘天泉厦门理工学院机械与汽车工程学院福建厦门361024 福建省客车及特种车辆研发协同创新中心福建厦门361024 汉诺威医学院事故调查科汉诺威30625

研究车辆与自行车碰撞事故中骑车人的下肢损伤风险,并确定车辆碰撞速度、自行车速度和骑车人特征等参数对骑车人下肢严重损伤的影响。为此,从德国深入事故数据库(German in-depth accident study,GIDAS)中挑选出471个带有骑车人下肢损... 详细信息

研究车辆与自行车碰撞事故中骑车人的下肢损伤风险,并确定车辆碰撞速度、自行车速度和骑车人特征等参数对骑车人下肢严重损伤的影响。为此,从德国深入事故数据库(German in-depth accident study,GIDAS)中挑选出471个带有骑车人下肢损伤的案例,并对其进行描述性统计和成组独立样本T检验,使用逻辑回归方法建立自行车骑车人下肢严重损伤风险函数模型,分析车辆碰撞速度、自行车速度和骑车人特征(年龄、身高和体重)对骑车人下肢严重损伤风险的影响。结果表明:车辆碰撞速度、骑车人年龄和体重是影响骑车人下肢严重损伤的显著性因素,其中车辆碰撞速度影响最为显著,其次是年龄和体重,且骑车人的下肢严重损伤风险与车辆碰撞速度、骑车人年龄和体重呈正相关。当汽车碰撞速度为55 km/h时,骑车人下肢严重损伤风险几率为50%。

关键词：骑车人下肢损伤风险逻辑回归模型车辆碰撞速度骑车人年龄和体重

The Global Fur Industry： Trends, Globalization and Specialization

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Journal of Agricultural Science and Technology(A) 2014年第7期4卷 543-551页

作者： Henning otte Hansen Department of Food and Resource Economics University of Copenhagen Frederiksberg C 1958 Denmark

The fur industry and the entire fur cluster are in many ways an interesting and instructive example from which many lessons can be learned. Up to now, the international fur industry has not been thoroughly described or analyzed. A major reason is the rather limited availability of national and international statistics about the fur sector. This article analyzes the production and international trade in fur based on information from official statistics, trade associations, companies, scientific papers and reports, interviews with experts, etc.. Markets and market conditions play a very important role with regards to the fur sector, and the price of fur is volatile in the short and long run. A new world trade pattern and international specialization have emerged in recent years. The comparative advantages of the fur sector change along the fur value chain, while China＇s position on the global fur market has changed significantly.

关键词： Fur industry mink production fur garment international trade fur cluster.

Food Crises and Market Mechanisms

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Journal of Environmental Science and Engineering(B) 2014年第1期3卷 30-48页

作者： Henning otte Hansen Department of Food and Resource Economics University of Copenhagen Frederiksberg C 1958 Denmark

Since the 1950s, there have been several food crises with severe humanitarian, economic, political and market-related consequences. In the last decade, food crises occurred during 2007-2008 and again in 2010-2011. In the paper, the main explanations for the food crises are discussed with a focus on the 2007-2008 food crisis, and the main causes are divided into temporary/random and structural/long term and are listed. Although there are a large number of factors, the size of reserves, speculation and bioenergy seem to be significant causes of the rapidly increasing food prices which were a major cause of the food crisis. The consequences of the food crisis in 2007-2008 in particular are discussed, and some major lessons learnt are listed. Also, the present market situation is assessed, the conclusion of which is that there does not seem to be an immediate risk of another food crisis occurring in the short term. However, international cereal reserves are still vulnerable and lower compared to the level in the 1990s.

关键词： Food crises food prices reserves lessons consequences.

Frequency Ratio Analysis of Mass Movements in the Xiangxi Catchment, Three Gorges Reservoir Area, China

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Journal of Earth Science 2010年第6期21卷 824-834页

作者： Dominik Ehret Joachim Rohn Christian Dumperth Susan Eckstein Stefanie Ernstberger Karel otte René Rudolph Johannes Wiedenmann 项伟毕仁能 Department of Applied Geology University of Erlangen-Nuremberg Faculty of Engineering China University of Geosciences

In 2003, the Three Gorges Project （TGP, China）, currently the world＇s largest hydroelectric power plant by total capacity, went into operation. Due to large-scale impoundment of the Yangtze River and its tributaries and also due to resettlement, extensive environmental impacts like land use change and increase of geohazards are associated with the TGP. Within the Yangtze Project, we investigate these effects for the Xiangxi （香溪） catchment which is part of the Three Gorges Reservoir. The aim of this study is to evaluate the susceptibility for mass movement within the Xiangxi River backwater area using geographic information system （GIS）. We used existing mass movements and the conditioning factors （geology, elevation, slope, curvature, land use, and land use change） for analyzing mass movement susceptibility. Mass movements and geology were mapped in the field to establish a mass movement inventory and a geological map. Land use and digital elevation model （DEM） were obtained from remote-sensing data. We determined the relation between mass movements and the conditioning factors by using the frequency ratio method and found strong relation between mass movements and both natural and human-influenced conditioning factors.

关键词： mass movement susceptibility GIS frequency ratio Xiangxi catchment Three Gorges Reservoir.