简介:TheChinesemodelhasafairlybiginfluenceinAfrica.Eversincereformandopening-up,Chinahasbeenfocusingonthecentraltaskofeconomicconstruction,whichbroughtrapideconomicgrowth,strengtheningcomprehensivenationalpower,improvinglivesofthepeopleandextendinginternationalinfluence.ThesuccessoftheChinesemodelhasarousedmuchinterestintheworld,especiallyAfrica,andproducedpositiveeffects.Itistheoutcomeofacombinationofseveralfactors,suchastheattractionofChina'sdevelopment.theimpetusproducedbythatdevelopmentandtheappealofChina'sfriendlypolicies.Nevertheless,ChinaisnotgoingtosellitsmodelandultimatelyAfricahastocarveoutitsownwayofdevelopment.
简介:AbstractPurpose:Terminal performance of a bullet in human body is critical for the treatment of gunshot injury and optimization of bullet design. The effects of the impact velocity (v0) and the impact attack angle (δ0) of the bullet on its terminal performance was investigated, using a new evaluation method (called expansion method) based on the expansion of cracks and the permanent cavity wall in ballistic gelatin.Methods:Ballistic gelatin was used to simulate human body. The 7.62 mm × 39 mm rifle bullets with different v0 (600-760 m/s) and δ0 (0°-6°) were fired into the gelatin blocks. The gelatin block was cut into slices of about 20 mm thickness. The cracks and the permanent cavity on each slice were obtained manually. The damaged gelatin was determined using two methods: expanding the permanent cavity but ignoring the cracks, and expanding both the permanent cavity and the cracks. The relations between the damaged gelatin and v0 and δ0 were obtained using linear fitting method.Results:According to the distribution of the damaged gelatin along the penetration depth, the damaged gelatin block could be divided into two parts: the less damaged part and the severely damaged part. The length of the less damaged part depends mostly on δ0; while the average damaged area of this part depends on both δ0 as well as v0. The cracks contributed significantly to the total volume of damaged gelatin, particularly when the expansion was larger than 1.9 mm. The total damaged gelatin increases with v0, δ0 and the expansion extent. The average length of equivalent cracks grew with v0 and δ0 when considering the cracks, and decreased with v0 when ignoring the cracks.Conclusion:The expansion method is suitable to investigate the influence of different factors of bullets on their terminal performance. The characteristics of the damaged gelatin have a linear relationship with the initial attack angle (δ0) and the initial velocity (v0) of the bullet.
简介:反应粉末水泥(RPC)的三种类型的影响行为用测试方法的裂口Hopkinson出版社酒吧(SHPB)被学习。这些RPC分别地与0%,3%,和4%的钢纤维体积部分被准备。压力紧张关系,紧张率敏感阀值价值,动态力量增加因素,弹性的模量和使遭到影响负担的这些RPC标本的失败模式被调查。从测试,50s1的紧张率敏感阀值价值被获得。试验性的结果看了那紧张率什么时候从阀值价值增加了到RPC的最大的压力增加了大约20%的95s1,,RPC的弹性的模量增加了大约30%。当使遭到了影响时,有钢纤维加强的RPC标本的失败模式与RPC矩阵标本的很不同装载。在装载率的类似的影响下面,在钢纤维开发的裂缝增强了RPC标本,虽然RPC矩阵标本被分解为小片。
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简介:Inthenext5to10years,theworldmaywellseetwo'risings'-therisingofthedevelopingcountriesasagroup,andtherisingofAsia-Pacificasaregion.Theworldgeopoliticalpicturewouldshifteastwardsaccordingly.Ontheworldstrategicmap,thedevelopingcountriesandtheAsia-PacificregionwouldholdasuperiorpositionandthedevelopedcountriesandtheEuro-Atlanticwouldhavearelativelyinferiorposition.Assuch,wewillseealotofchangesintheconceptofgeopolitics.ToChina,thesechangespresentbothopportunitiesandchallenges.TheauthorbelievesthatChinashouldkeeptoitsstrategicguidelines,i.e.'risingpeacefully'and'keepingalowprofile',putitsgeo-strategicattentionontheAsia-Pacific,activelycreateanenvironmentfavorabletoitsdevelopment,andeventuallymakeitspeacefulrisingareality.
简介:of ,industry ,mainly 
简介:EnglishlinguisticimperialismisthatthedominanceofEnglishasaworldlanguageandsetsouttoanalysishowthelanguagebecamesodominant.ItlooksatthespreadofEnglish,inordertoascertainwhetherthelanguagehasactivelypromotedasaninstrumentoftheforeignpolicyofthemajorEnglish-speakingstates,andifso,inwhatways.Last,itwillprovideadescriptionoflanguagepedagogy,thescientificstudyoflanguagelearningandlanguageteaching,hasbeenisolatedfromthesocialsciencesandpoliticaldisconnection.