切削力的理论计算

一、绪言 切削力在金属切削科学中占有一定的地位,它是设计和使用机床刀具的必要数据,并影晌工作的光度和精度。因之很多学者对它进行了一系列的研究工作,如И.А基麦,К.А .斯法雷金,А.А.柏列克斯,Т.Н.罗拉日,Н.Н.萨来也夫,В.А.克列伏乌豪夫,А.М.罗森贝尔格等等,研究人虽多,公式也多,但实际上有许多公式是出於同一     

Automobile Wind Tunnel Test(英文)

ZhouYupingThekeyproblemofautomobilewindtunneltestishowtomeasuretheforwardaxleandbackwardoneseparately.Now,seriesmeasurementwithdoublebalancehasbeenadapted.Andgroundsimulationnecessaries,stingsandsealinginstrumentshavebeencoordinatedwholly.Thetestingresultsanddiscussionindicatethattheplanabovementionedisanewmeasurementway.Forgroundsimulati0n,14.8m×7.4mlargesetfloorhasbeenused.AfternaturalIypumping,theboundarylayerdepthoftestingsectioncenterislessthan100mm.Thenewsetofsmokeflowinstrunlentshasa…     

Prof.W.B.Lee Was Invited to Be Honorary Member of Editorial Board of JNUAA

Professor W.B.Lee is the director of Department of Manufacturing Engineering of Hong KongPolytechnic University and a scholar of great attainments in manufacturing science and technology,ma-terials processing,ultra-precision machining.At present he has published over90 papers on the variousjournals and international conferences,2 books and2 keynote papers.Because of his research reputationProfessor W.B.Lee has been invited to be honorary professor of Nanjing University of Aeronautics andAstronautics(NUAA)in1996.On14 Decemeber,this year,Prof.W.B.Lee was one again invited tobe honorary member of Editorial Board of Journal of Nanjing University of Aeronautics and Astronautics(JNUAA).NUAA specially promulgates the formal document for Prof.W.B.Lee and he accepted withpleasure the honorary title.     

高超声速球模型尾迹电子密度试验研究

在中国空气动力研究与发展中心超高速所弹道靶上利用电子密度测量系统进行了高超声速钢球模型、铜球模型尾迹电子密度测量.电子密度测量系统由8mm微波干涉仪系统、开式微波谐振腔测量系统和闭式微波谐振腔测量系统组成.钢球模型直径φ10mm,速度分别为5. 8、5. 5、5. 6和5. 5km/s,对应的飞行环境压力分别为2. 79、5. 32、5. 85和10. 91kPa.铜球模型直径φ10mm,速度分别为5. 6、5. 6、5. 7和5. 5km/s,对应的飞行环境压力分别为1. 33、4. 79、5. 89和10. 91kPa.结果表明:(1)在压力5. 3~1lkPa范围内、速度约5. 5km/s试验条件下,压力越高,钢球模型的尾迹电子密度相应增大,电子密度的衰减速度较快;(2)在压力1. 3~6kPa范围内、速度约5. 6km/s试验条件下,压力越高,铜球模型的尾迹电子密度相应增大,电子密度的衰减速度较慢;(3)在压力约10. 7kPa、速度5. 5km/s试验条件下,铜球模型的尾迹电子密度衰减速度比钢球模型慢得多.     

Miss D.D

萱萱的妈妈D.D,是圈内少见的低调星妈。D.D.17岁就在母亲的反对下,坚持生下了萱萱,独立抚养她,每天靠着一副好歌喉在pub演唱跑场子,培养萱萱念音乐。D.D.的嗓音充满性感和沧桑能量,非常动人。然而,D.D.的音乐梦却在母亲的角色中,一直被紧紧地压在内心深处而从不释放。     

可重复使用飞行器翼肋的再入瞬态温度分布计算

对翼肋的温度分布进行求解,并把计算模型和求解结果与F.V.Pohle和William Ko.进行比较分析,结果表明,所用的模型比F.V.Pohle的更合理,计算结果和William Ko.的比较吻合。     

弹体脉动压力特征的实验研究

针对弹体模型进行了表面脉动压力特性实验研究,实验马赫数M∞=0. 8、0. 84、0. 86、0. 92、1. 0、1. 15、2. 0、2. 5,实验迎角α=-5°、-3°,0°、3°、5°,沿弹体轴向测量了14个特征点的脉动压力,得到了弹体表面测点的脉动压力系数、频谱曲线以及相关性系数等实验数据.结果表明:脉动压力系数总体上随马赫数增加而降低.不同马赫数.迎角α=0°的条件下沿轴向各测点压力脉动之间的空间相关性有类似的分布规律,且各测点脉动压力基本互不相关.在实验的迎角下,脉动压力系数在弹体表面曲率变化较小的位置基本上不随来流迎角的改变而变化,膨胀拐角肩部位置的脉动压力系数随着迎角的改变而变化较大.超声速来流的功率谱能量峰值所对应的主频出现明显的低频特征;跨音速来流时特征频率随着马赫数的增加而增大,功率谱能量峰值位于特征频率处.     

梦中每迷的故土雨城雅安

从靠近永丰立交桥家中驱车出来,转弯便驶上了成雅高速公路.路况很好,便放心地加大了油门,仪表盘的指针一个劲地往上蹿.姜育恒的那张十年精选CD还没有放完,车便到了金鸡关隧道,雅安的入口.看看表,才一个小时零十分钟.真快呀.再想想以前至少四五个小时的情形,简直不可同日而语.     

基于微细梁振动位移的微尺度射流测速方法

实验研究微尺度射流流场中微细梁发生的振动过程,并提出基于该原理测量微尺度射流速度.实验使用长度56. 2mm、直径约0. 07mm铜丝作为微细梁,使用直径约0. 36mm喷管产生的微尺度射流.使用高速摄影仪观察射流流速在2. 7~27. 3m/s间梁振动的变化.试验结果发现当射流喷嘴对准梁3/5处时,振动过程中振幅随射流速度上升.而当射流喷嘴对准梁的9/10和3/4处时,在高流速下,振幅不随流速上升.使用霍尔传感器和磁铁测量梁的振动,当喷嘴对准梁的3/4处,霍尔传感器输出电压有效值随射流流速线性增长.但在其他位置,由于磁铁改变了梁的均匀结构,振动随流速的变化不规律.     

"汉塾与我大?"丁学良提问郎酒《郎酒品牌与企业文化》研讨会实录

2009年郎酒冠名春晚,红花郎名声大震.汶川地震,郎酒捐款2130万元,加上物资捐赠,总金额超过5000万元.郎酒作为一个民营企业,其社会责任感有目共睹.2008年,郎酒与中央电视台军事节目中心结成战略合作伙伴.     

平常心进退有道

◎万象更新时进退平常心 似乎一切都在改变.昨天的新闻,可能成为今天的历史.两个月做出一个决定,可以被一分钟的思考推翻.自己在变,周围的人在变.甚至每一种事物,都以更迅速的方式变化着,让人来不及思考,又匆匆上路.     

在二郎镇

二郎镇在赤水河的这边,习酒镇在赤水河的那边.都是盆地的一半,外边有岩.河壁赭红.都是斜坡而上.象是剖开的一个苹果.风水上称作大阴的地方。大阴为众妙     

本刊“微重力环境工程”题录

1张秀清.许达明.失重环境对火箭导弹工程的影响(综述)‘1973(2).2刘春辉.失重对宇航器的影响(文献综述).1975(3).3刘春辉译,冯振兴校.用于空间运载器流体系统研究的零重力设备(译文).1975(3).‘褚桂敏译,张秀清校.人马座液氢贮箱相似模型的低重力重定位(译文).19”(2).5许达明.相似方法在失重环境试验中的应用.1978(3).6张秀清.失重环境(一)ACS系统液体管理,1 978(3).7应桂炉.大型运载火箭的推进剂液体控制问题.1980(1).8张秀清、失重环境与液体管理,1980(1).9褚桂敏.低g晃动与飞机低g飞行试验.1981(2).10方良玉,张景芳.液体火箭贮箱中的…     

浑函光芒三苏祠

北宋时期.眉山出了“一家三父子.都是大文豪“的苏洵、苏轼、苏辙.这真是前无古、后无今的奇迹.以苏轼为代表的三苏父子.以其深邃的哲学思想、卓著的政治实践、辉煌的文学成就和丰富的人生体验而“雄视百代,自作一家,浑函光芒“.……     

Modeling and Simulation for Refueling Boom and Receiver in Coupled Mode

In coupled mode,the major problem of boom refueling system is undesirable nozzle loads.An automated load alleviation system(ALAS)is needed to alleviate nozzle loads.In order to simulate dynamic of the system and to validate ALAS,dynamic model is developed.Two models are established,which are the static model and the moving model,named after the two relative states between the fixed boom and the extension boom.Kane method is employed as main method considering system′s multi-body characteristics.D′Alembert′s principle is used to calculate nozzle loads.Simulation is conducted to research the effects of position disturbance and velocity disturbance on nozzle loads.Results indicate that position disturbance plays a more significant role in inducing nozzle loads.A fuzzy control law based ALAS is validated using the formulated model.It is concluded that this model can simulate system dynamic and validate ALAS.     

OPTIMAL DESIGN FOR STATOR OF THREE-DOF ULTRASONIC MOTOR

A 3-DOF ultrasonic motor with a cylindershaped stator and a spherical rotor is developed. The motor provides 3-DOF rotation around x, y. and z-axes implemented by two second order bending modes with orthogonality and one first order longitudinal mode of the stator, The three modes must satisfy some conditions. In our previous research, in order to satisfy these conditions, a parameter fitting design method is used. However, it is an experiential design method with low efficiency and costs much time, sometimes it even cannot find a desired solution, This paper puts forward an optimal design method for the stator. Based on the method, an optimization program is developed in MATLAB environment. Using the program, a new prototype of 3-DOF ultrasonic motor is designed. Its stator has diameter of 20 ram. height of 67 mm, and mass of 157 g. Experimental results show that the measured stators‘ modal frequencies and modal shapes are in good consistent agreement with the results obtained by the optimal design program.     

Polysaccharide from Loquat Leaves to Prepare Hierarchical Porous Carbon as a Matrix for Active Sulfur

Fossil fuel exhaustion and overdevelopment usually lead to a recession,which is worsened by the environmental pollution.So it is of high priority to develop high-efficiency energy storage device.Here,agreen and environment-friendly strategy is devised to fabricate carbon materials from biomass.By water extraction and alcohol precipitation,polysaccharide is extracted from loquat leaves.After calcining under high temperature,hierarchical porous carbon materials(HPCM)are obtained,possessing a variety of macropores,mesopores and micropores.Such ample and hierarchical pores enable the electrolyte infiltration and the buffering of the volume expansion of sulfur in repeated electrochemical reactions.The structure stability of the entire electrode can thus be well maintained.When evaluated as the scaffold for sulfur,the electrochemical performance of carbon/sulfur composite was tested.Even after 500 cycles,the reversible capacity is retained as high as 485.4 mA·h/g at the current density of 1.6 A/g.It also offers a notable rate capability,attaining the discharge capacity of 700.7 mA·h/g at 2 C.All the electrochemical performance results prove the feasibility of the proposed strategy.     

Navigating the Bamboo Sea

Changning County, Sichuan Province- The ants are on my trail. Thinking I've lost them, I stop to rest. But a few of them have battled their way up the steep path and are catching up to me. Soon I'll be done for. In desperation, I go off trail,weaving through grass so high it blocks out the sun.     

一种基于相关向量机的白细胞检出新方法

提出了一种基于相关向量机(RVM)的白细胞检出新方法.首先,借助RVM对一维直方图进行拟合,获得稀疏的相关向量.然后,直接从这些数量有限的相关向量中筛选出所需的阈值.最后,基于前一步得到的阈值,将完整、连续的白细胞区域从原始图像中分割出来.该方法已成功地应用于白细胞检出,有效地降低了由光照和染色引起的干扰.该方法计算效率高,无需设置额外参数.实验结果表明了该方法的优良性能.     

PREFACE

正The special issue on structural health monitoringintegrity management(SHMIM)was inspired by the 3rd International Conference on SHMIM,held in Chengdu,China,October,2016.Thanks to the guest editors,Prof.CAO Maosen and Prof.DING Keqin,for their devoted help,this issue finally found a chance to start.