<tt id="6hsgl"><pre id="6hsgl"><pre id="6hsgl"></pre></pre></tt>
          <nav id="6hsgl"><th id="6hsgl"></th></nav>
          国产免费网站看v片元遮挡,一亚洲一区二区中文字幕,波多野结衣一区二区免费视频,天天色综网,久久综合给合久久狠狠狠,男人的天堂av一二三区,午夜福利看片在线观看,亚洲中文字幕在线无码一区二区
          Global EditionASIA 中文雙語Fran?ais
          Opinion
          Home / Opinion / Op-Ed Contributors

          Imagine a train running at 4,000 km/h

          China Daily | Updated: 2017-09-02 10:20
          Share
          Share - WeChat

          File photo / China Daily

          The China Aerospace Science and Industry Corp announced at a forum in Wuhan, Central China's Hubei province, on Wednesday that it had launched research and development in hyperloop, a futuristic mode of transportation that could allow trains to run at speeds of up to 4,000 kilometers an hour. CASIC said they would design hyperloop in a way that would allow "vehicles" to run in low vacuum so as to minimize air resistance, and use magnetic suspension technology to minimize friction. Is hyperloop really possible? China Daily's Zhang Zhouxiang interviewed an expert on the subject and translated CASIC's explanation about hyperloop. Excerpts from both follow:

          Technology faces major challenges

          Zhao Chunfa, a professor who specilizes in magnetic suspension trains at Southwest Jiaotong University

          Hyperloop, or, in more technological terms, ultra high-speed magnetic suspension transportation in vacuum tubes, is the direction of our future research. It will not only make traveling more convenient, but also help to improve many related technologies.

          However, currently we face some major challenges in that field. For example, hyperloop involves high-temperature superconductivity technology, for which we need materials of the tube to be superconductive to relatively "high" temperatures. But when a train would run at speeds of up to 1,000 km an hour, it will generate lots of heat and vibration in the vacuum tube. The question is: Will the materials remain superconductive to "super high temperatures" and violent vibration?

          Besides, for a train to run at more than 1,000 km an hour, its rails have to be very, very smooth, in order to keep the train stable. A flaw of even 0.1 millimeter might cause the train to be unstable making passengers uncomfortable. Sometimes such a flaw could result in the train jumping the rails. And even the most advanced technology today cannot ensure our rails are smooth to that extent over thousands of kilometers.

          Some might argue that the proposed hyperloop technology would allow the train to operate in vacuum tubes, but it would still be a mode of rail transport and has to meet the standards.

          These are only two of the challenges that hyperloop faces. Others include safety concerns, difficulties in making thousands of kilometers-long vacuum tubes, and extremely high costs. This is not to say hyperloop as a technology is a failure ab initio, but it is necessary to conduct fundamental research first, so as to make it practicable.

          Company confident about meeting goal

          Mao Kai, engineer in charge of the hyperloop program at CASIC

          The concerns over hyperloop transportation causing harm to passengers are unnecessary. High speed does not cause any damage to the human body; it is high acceleration that does. Hyperloop trains are expected to have a higher maximum speed than aircraft, but they would accelerate much slowly. For hyperloop trains to cause harm to the human body, their rate of change of velocity would have to be faster than that of an aircraft, which would not be the case.

          Besides, CASIC is not the only organization engaged in hyperloop R&D. US-based companies HTT and Hyperloop One are also conducting such R&D, with the latter even using the term "hyperloop" in its name.

          Compared with the two companies which aim to increase a train's speed to 1,000 km an hour, our goal is to raise it step by step to 4,000 km an hour. And we are confident of reaching that goal, because we are using electromagnetic force to propel hyperloop "vehicles" forward, while the other two companies plan to run hyperloop "vehicles" on wheels.

          As for the major advanced technologies needed to develop hyperloop transportation, including ultrasonic technology, high-temperature superconductive magnetic suspension, as well as simulation and modeling technologies, we are now playing leading roles in all those fields. In other words, we have more mature technologies than our counterparts in other countries at our disposal and we are confident about succeeding in our R&D.

          Most Viewed in 24 Hours
          Top
          BACK TO THE TOP
          English
          Copyright 1995 - . All rights reserved. The content (including but not limited to text, photo, multimedia information, etc) published in this site belongs to China Daily Information Co (CDIC). Without written authorization from CDIC, such content shall not be republished or used in any form. Note: Browsers with 1024*768 or higher resolution are suggested for this site.
          License for publishing multimedia online 0108263

          Registration Number: 130349
          FOLLOW US
          主站蜘蛛池模板: 久久精品女人天堂av免费观看| 男女猛烈激情xx00免费视频| 午夜福利国产一区二区三区| 四川丰满少妇无套内谢| 久爱www人成免费网站| 久久精品免视看国产成人| 男同精品视频免费观看网站| 亚洲影院丰满少妇中文字幕无码 | 免费看女人与善牲交| 99久久精品免费看国产电影| 国产成人综合久久二区| 无码人妻丰满熟妇区五十路| av亚欧洲日产国码无码| 无码一级视频在线| 麻豆国产传媒精品视频| 小嫩模无套内谢第一次| 人摸人人人澡人人超碰手机版| 欧美视频精品免费覌看| 少妇午夜福利一区二区三区| 中文字幕亚洲精品人妻| 91中文字幕在线一区| 成人免费777777| 中文字幕无码av不卡一区| 亚在线观看免费视频入口| 亚洲中文精品一区二区| 粉嫩少妇内射浓精videos | 亚洲理论在线A中文字幕| 亚洲综合伊人五月天中文| 玩弄漂亮少妇高潮白浆| 毛片一区二区在线看| 久久久久女教师免费一区| 日韩丝袜人妻中文字幕| 一本久道久久综合狠狠躁av | 狠狠综合久久av一区二| 伊人久久大香线蕉综合观| 国产精品国产三级国AV| 国产精品久久久久久久专区| 男男高h喷水荡肉爽文| 亚洲色偷偷色噜噜狠狠99| 无套内谢少妇高清毛片| 久久精品A一国产成人免费网站|