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1.
<正>后轮转向、减振器液压缓冲块、拖拽臂后悬架,雷诺运动/赛车部门Renault Sport推出的新一代Megane RS为钢炮提供了另外一种存在方式。这一次,本田Civic Type-R可得小心点了2017年法兰克福车展前几个月,雷诺运动/赛车部门Renault Sport把一小组记者召集到它藏在巴黎市郊、门面不大的总部所在地。记得Renault Sport的老板Patrice Ratti自信而且轻松地介绍着全新的  相似文献   
2.
三王之战     
<正>保时捷911GT3、GT3RS和GT2RS处于整个911车型性能的最顶端,它们三个对比谁会成为赢家却是—个耐人寻味的问题保时捷会将每一代911发挥的潜力都挖掘到极限,派生出各种不同取向的车型,但不会同时销售几种不同车型。所以有什么能比把991.2车系的三款顶尖车型——911GT3、GT2RS和GT3RS聚齐在英国Anglesey来一场测试更符合保时捷70周年纪念的主题呢?  相似文献   
3.
伟大的希冀     
<正>阿斯顿马丁期望全新Vantage能够成功,但它需要先争得几个不可小觑的竞争对手的同意,比如奥迪R8 V10 Plus、迈凯轮540C和保时捷911 Carrera 4 GTS终于,我必须要感叹一声,终于开上了阿斯顿马丁Vantage。之前无论是在北极圈冰面上工程车的测试还是葡萄牙盛大发布会上的体验都像是被别人刻意安排好的节目。不能否认,Vantage在柏油路面上确实快得惊人,在赛道上又可以随心漂移,但仅凭这两项很难让人对于  相似文献   
4.
This paper presents a detailed diagnostic analysis of hydrographic and current meter data from three, rapidly repeated, fine-scale surveys of the Almeria–Oran front. Instability of the frontal boundary, between surface waters of Atlantic and Mediterranean origin, is shown to provide a mechanism for significant heat transfer from the surface layers to the deep ocean in winter. The data were collected during the second observational phase of the EU funded OMEGA project on RRS Discovery cruise 224 during December 1996. High resolution hydrographic measurements using the towed undulating CTD vehicle, SeaSoar, traced the subduction of Mediterranean Surface Water across the Almeria–Oran front. This subduction is shown to result from a significant baroclinic component to the instability of the frontal jet. The Q-vector formulation of the omega equation is combined with a scale analysis to quantitatively diagnose vertical transport resulting from mesoscale ageostrophic circulation. The analyses are presented and discussed in the presence of satellite and airborne remotely sensed data; which provide the basis for a thorough and novel approach to the determination of observational error.  相似文献   
5.
弯道激情     
正保时捷在Gayman上用一台水平对置四缸机,替代了原来的水平对置六缸机,不知它还能否在比利牛斯山的山路上证明自己——它不比任何一位前辈逊色机舱内传来了机长广播的声音,"乘务员请注意,我们将在10分钟后降落"。紧接着Bing的一声,头顶上面的安全带指示灯亮起,我前面一位坐在过道旁边的先生刚好望向机尾的卫生间,脸色瞬间变得紧张起来,不知是应该起身前往还是等待降落,to pee or not to pee,纠结如此,想必他一定是一个英国人。  相似文献   
6.
Marine ecosystem models are becoming increasingly complex and sophisticated, and are being used to estimate the effects of future changes in the earth system with a view to informing important policy decisions. Despite their potential importance, far too little attention has been, and is generally, paid to model errors and the extent to which model outputs actually relate to real-world processes. With the increasing complexity of the models themselves comes an increasing complexity among model results. If we are to develop useful modelling tools for the marine environment we need to be able to understand and quantify the uncertainties inherent in the simulations. Analysing errors within highly multivariate model outputs, and relating them to even more complex and multivariate observational data, are not trivial tasks. Here we describe the application of a series of techniques, including a 2-stage self-organising map (SOM), non-parametric multivariate analysis, and error statistics, to a complex spatio-temporal model run for the period 1988–1989 in the Southern North Sea, coinciding with the North Sea Project which collected a wealth of observational data. We use model output, large spatio-temporally resolved data sets and a combination of methodologies (SOM, MDS, uncertainty metrics) to simplify the problem and to provide tractable information on model performance. The use of a SOM as a clustering tool allows us to simplify the dimensions of the problem while the use of MDS on independent data grouped according to the SOM classification allows us to validate the SOM. The combination of classification and uncertainty metrics allows us to pinpoint the variables and associated processes which require attention in each region. We recommend the use of this combination of techniques for simplifying complex comparisons of model outputs with real data, and analysis of error distributions.  相似文献   
7.
正在这个倾心电动车的时代,马自达逆潮流而动,用全新的Skyactiv-X系列发动机证明内燃机时代还没有走到尽头。这一代全新机型将在2019年率先装配全新一代马自达3/Axela,我们受邀率先体验了这一新技术我想马自达一定会对自己每一分开销都精敲细打:一年160万的产销屋在这个巨无霸横行的世界上显得实在微小,因而每一份收获都来之不易。不过相比大众、丰田、现代或是通用集团,马自达又拥有出色的独立性,一个确实存在但容易忽略的优势。正因为如此,它可以充分控制自己的技术路线。  相似文献   
8.
Marine systems models are becoming increasingly complex and sophisticated, but far too little attention has been paid to model errors and the extent to which model outputs actually relate to ecosystem processes. Here we describe the application of summary error statistics to a complex 3D model (POLCOMS-ERSEM) run for the period 1988–1989 in the southern North Sea utilising information from the North Sea Project, which collected a wealth of observational data. We demonstrate that to understand model data misfit and the mechanisms creating errors, we need to use a hierarchy of techniques, including simple correlations, model bias, model efficiency, binary discriminator analysis and the distribution of model errors to assess model errors spatially and temporally. We also demonstrate that a linear cost function is an inappropriate measure of misfit. This analysis indicates that the model has some skill for all variables analysed. A summary plot of model performance indicates that model performance deteriorates as we move through the ecosystem from the physics, to the nutrients and plankton.  相似文献   
9.
MULTIPLETRANS-ACTINGFACTORSMEDIATETHEINDUCTIONOFC-FOSINVASCULARSMOOTHMUSCLECELLSChenYanqun;BartekRydzewski,AllenJ.Naftilan(De...  相似文献   
10.
The design approach of H∞ autopilot for autonomous underwater vehicles (AUVs) is proposed. Comprised by the three sub-controllers,i.e. speed,heading and depth controllers,the designed autopilot has advantage over existing H∞ control of AUVs. The overshoot in speed,heading and depth control systems under step commands is restricted by refining the weighting function for robust stability. The dynamic performance of heading and depth control systems is improved by feeding back yaw rate and pitch angle,respecti...  相似文献   
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