这样的交通工具汽车耗资不菲，而且要求驾驶者具备像训练有素的飞行员一样的驾驶技巧;不仅如此，在研制过程中还面临工程学方面的严峻挑战。

马克•摩尔是美国国家航空航天局兰利研究中心(位于汉普顿)汽车系统项目组“个人空中交通工具(PAV)”小组的负责人，他说：“当你试图将各个方面组合起来时，得到的是一辆最糟糕的车：非常笨重，速度又慢，价格还高，总之驾驶起来很不方便。”

但波音公司同时也在考虑，在上千辆“飞车”进入空中的情况下如何对空中通道进行管理，防止交通陷入彻底的混乱。

波音公司研发部门“幻影工程队”的副总裁迪克•保罗说：“最关键和最精彩的是设计出这种交通工具本身，但是我们也在全力考虑当这样一支车队投入运行后可能出现的所有情况。”

关于如何解决这个问题，以往就有一些建议，包括使用人工智能系统来防止空中交通工具之间发生碰撞。

B.一篇阅读文章。

Gauri Nanda sees a wearable computer as a...handbag -- one that's built out of four-inch squares and triangles of fabric, with tiny computer chips embedded in it.

Assembled together with Velcro that conducts electricity, these pieces form a bag that looks, feels, and weighs like your typical leather purse.

That's where the similarities end: This bag can wirelessly keep tabs on your belongings and remind you, just as you're about to leave the house, to take your wallet. It can review the weather report and suggest that you grab an umbrella -- or your sunshades. This purse can even upload your favorite songs onto your scarf.

Sure, a computing purse and scarf set may seem like the stuff of science fiction. But these devices, part of next generation of wearable computers, could become commonplace within a few years. Unit shipments of such wearable computers -- purses, watches, shirts -- should rise from 261,000 last year to 1.39 million in 2008, according to the tech research firm IDC.

Powering this market are advancements in design and in fabric-embedded electronics. Over the last two years, DuPont (DD ) created new fibers called Aracon, made of Kevlar, that are superstrong, can conduct electricity, and can be woven into ordinary-looking clothes. And chipmaker Infineon (IFX ) developed chip packaging allowing wearable computers to be washed, even in the heavy-duty cycle.

As a result, these new wearables are a far cry from the clunky and downright silly versions of the recent past, which often required users to be wrapped in wires, type on their stomachs, and sport an unseemly display on their foreheads. "Cyborg computing was very clunky, very bulky machines that people didn't want to carry around," says Nanda, a researcher at the Massachusetts Institute of Technology in Cambridge, Mass. "Our bags feel and look like bags."

Unlike their predecessors, these new wearable computers also make economic sense. When her bag becomes commercially available in two to three years, Nanda expects it will cost around $150, which is the price of an average leather purse. Only "it's fun, you can rip apart and put together a computer," she says.

Here's how the bag works: You place a special radio-signal-transmitting chip onto your wallet. A similar radio in your purse picks up the signal and notifies you that you've forgotten to take your wallet. In turn, sensors on your purse's handles will notify the computer that you've picked up the purse and are ready to go.

Such unobtrusive, inconspicuous, and fun devices should grab more than 80% of the total wearable computing market by 2008, while cyborgian wearable PCs will remain a niche, says IDC analyst Kevin Burden. Already, these new kinds of wearables are being adopted for use in markets like auto repair, emergency services, medical monitoring -- and even, increasingly, for consumers at large.

Wearables are also slowly making their way into the auto-repair market. A company called Microvision (MVIS ) recently introduced its Nomad head-mounted display. It covers one eye, but it's see-through, allowing auto technicians to examine the innards of a car and check them against on-screen computer drawings at the same time. It comes as a baseball cap clip-on, to be more unobtrusive.

So far, it's a hit: At Jim Fisher Volvo dealership in Portland, Ore., which has been testing the system for about seven months, productivity of technicians went up 10% to 20%, says Service Manager John Prosser. Better yet, customers talking to technicians who are wearing these contraptions also are more likely to agree to repairs, pushing revenue up 15% to 18%. Says Prosser: "This makes [technicians] want to get involved and to cross this bridge of reluctance" in using a new technology.

Indeed, many more people will want to cross that bridge in the coming years -- making for a booming market for wearable computers that don't look like something out of an old Star Trek episode.

最新型的可穿着电脑产品在外观方面与普通衣物几乎没有什么两样，而售价的降低和功能的丰富也许会使它成为未来人类不可或缺的工具之一。

The latest generation of these ever-smarter garments look like ordinary clothes, assembled together with Velcro that conducts electricity, these pieces form a bag that looks, feels, and weighs like your typical leather purse.

你能否想象一台仅仅4英寸大小的电脑?用户可以方便地随身携带，重量与一件普通的皮夹克差不多。它，就是“可穿着式电脑”。最新型的可穿着电脑产品在外观方面与普通衣物几乎没有什么两样，而售价的降低和功能的丰富也许会使它成为未来人类不可或缺的工具之一。

据美国《商业周刊》3月8日报道，这种“小家伙”可以帮助用户通过无线方式与主人的其他财物保持联系，并随时随地提醒用户一些生活细节。当用户离开房间的时候，它会乖巧地提醒主人不要忘记携带钱包;在主人出行时，它会自动查询天气预报，帮助主人做到未雨绸缪;它甚至还可以在主人穿着的围脖中加入喜欢的歌曲。