克里斯蒂：打造尽善尽美的电梯系统

You press a button and wait for your elevator. How long before you get impatient and agitated? Theresa Christy says 20 seconds.

你按下按钮，等待电梯到来。等多长时间会让你觉得不耐烦、想发火？特蕾莎·克里斯蒂(Theresa Christy)说：20秒。

As a mathematician steeped in the theories of vertical transportation at Otis Elevator Co., Ms. Christy, 55, has spent a quarter-century developing systems that make elevators run as perfectly as possible─which means getting most riders into a car in less than 20 seconds. 'Traditionally, the wait time is the most important factor,' she says. 'The thing people hate the most is waiting.'

作为奥的斯电梯公司(Otis Elevator Co.)精通垂直交通理论的数学家，55岁的克里斯蒂在25年的时间里致力于开发让电梯运行尽善尽美的系统──也就是说，在20秒之内让大多数乘客进入电梯。她说，传统上而言，等待时间是最重要的因素，人们最讨厌的事情就是等待。

Developed in the 19th century, elevators transformed urban living, real estate markets and skylines around the world. As an Otis research fellow, Ms. Christy gets to work on the toughest problems and on signature projects like the 1,483-foot-high Petronas Towers in Malaysia, for a time the world's tallest building.

出现于19世纪的电梯令城市生活、房地产市场和世界各地的城市面貌都发生了变化。作为奥的斯的研究人员，克里斯蒂需要解决最棘手的问题，并参与了诸多知名项目，比如高1,483英尺（约合452米）、曾经一度为世界最高建筑的马来西亚双子塔(Petronas Towers)。

During the recent $550 million upgrade of the Empire State Building, Ms. Christy was asked whether she could help get more people up to the observation deck. She said she couldn't get more people into a car but could move them up more quickly. So she increased the elevators' speed by 20%, to 20 feet per second. Now the cars can rise 80 floors in about 48 seconds, 10 seconds faster than before.

不久前帝国大厦(Empire State Building)投入5.5亿美元进行升级时，有人问克里斯蒂能否让更多的人上到观景平台。她说，她不能增加电梯轿厢运载的人员数量，但可以让电梯上升的速度更快。于是她将电梯的速度提高了20%，达到每秒20英尺（约6米）。现在电梯轿厢上升到80层楼只需大约48秒，比以前快10秒。

Ms. Christy strikes down one common myth─that 'door close' buttons don't work. Sometimes they do, sometimes they don't, she says. It depends on the building's owner.

克里斯蒂指出了一个常见的误区──关门按钮不管用。克里斯蒂说，电梯的关门按钮有时管用，有时不管用，这取决于建筑的所有者。

The challenges she deals with depend on the place. At a hotel in the holy city of Mecca in Saudi Arabia, she has to make sure that the elevators can clear a building quickly enough to get most people out five times a day for prayer.

她所面临的挑战随安装电梯的地点不同而不同。例如，在沙特阿拉伯圣城麦加的酒店里，她需要确保电梯能够迅速地把整栋楼的人运输下来，每天把基本所有人运上运下五次，满足他们的祈祷需求。

In Japan, riders immediately want to know which car will serve them─indicated by a light and the sound of a gong─even if the elevator won't arrive for 30 seconds. That way, people can line up in front of the correct elevator.

在日本，等电梯的人需要马上知道哪个电梯会最先到达（通过指示灯和铃声），即使电梯要30秒之后才能到达也没关系。这样人们就可以在正确的电梯门口排队等待。

Japan also boasts, in Ms. Christy's opinion, the smoothest, best-riding elevators. 'When you get into an elevator there, you sometimes think you are 'stuck' in the elevator because the motion is so smooth and quiet,' she says. But that service comes with extra costs and slower speeds.

在克里斯蒂看来，日本的电梯世界上最平稳，乘坐体验最佳。她说，有时你在日本乘坐电梯时，你会觉得电梯根本没动，因为那里的电梯的动作非常平缓，非常安静。但是这样的成本更高，电梯速度也较慢。

Another problem: How many people fit in an elevator? In Asia, more people will board a car than in Europe or New York, Ms. Christy says; Westerners prefer more personal space. When she programs an elevator system she uses different weights for the average person by region. The average American is 22 pounds heavier than the average Chinese.

另一个问题是：一个电梯轿厢里能装下多少个人？克里斯蒂说，亚洲的电梯轿厢里的人往往比欧洲或纽约多。西方人喜欢人与人相隔较大的空间。在为电梯系统编写程序时，根据地区的不同，她采用的个人体重数值也不同。美国人平均体重比中国人的多了22磅（合10公斤）。

At their core, elevators are a mode of transportation. Serving passengers well is constrained by the number of elevators, their speed, how fast their doors open and close, and how many people can fit in a car. In the U.S., these factors come together 18 billion times a year, each time a passenger rides an elevator.

究其本质，电梯是一种运输工具。电梯运载服务的质量受到了电梯的数量、速度、电梯开关门的速度以及轿厢容量的制约。在美国，所有电梯一年总计运载180亿人次。

That experience is at the heart of what Ms. Christy does. From her sparse second-floor office in a leafy office park in Farmington, Conn., she writes strings of code that allow elevators to do essentially the greatest good for the most people─including the building's owner, who has to allocate considerable space for the concrete shafts that house the cars. Her work often involves watching computer simulation programs that replay elevator decision-making.

人们乘坐电梯的体验是克里斯蒂工作内容的核心。克里斯蒂的办公室位于康涅狄格州法明顿市(Farmington)一个绿树成荫的办公区。在她风格朴素的二楼办公室里，克里斯蒂写下一串串代码，这些代码让电梯为尽可能多的人提供最好的乘坐体验──包括建筑的所有者，因为他们需要为容纳电梯的混凝土竖井分配大量空间。她还常常观看回放电梯决策过程的计算机模拟程序。

'I feel like I get paid to play videogames. I watch the simulation, and I see what happens, and I try to improve the score I am getting,' she says.

她说，我感觉我的工作就是玩视频游戏，观看模拟动画，了解发生了什么，然后努力提高我的分数。

Here is a typical problem: A passenger on the sixth floor wants to descend. The closest car is on the seventh floor, but it already has three riders and has made two stops. Is it the right choice to make that car stop again? That would be the best result for the sixth-floor passenger, but it would make the other people's rides longer.

有一个关于电梯系统设计的经典问题：六楼的人想乘电梯下楼，离他最近的电梯轿厢在七楼，但电梯里已经有三个人，而且已经停过两次。那么，让这个电梯再停一次是个恰当的选择吗？对于六楼的人来说，这是最好的结果，但会延长其他人乘坐电梯的时间。

For Ms. Christy, these are mathematical problems with no one optimum solution. In the real world, there are so many parameters and combinations that everything changes as soon as the next rider presses a button. In a building with six elevators and 10 people trying to move between floors, there are over 60 million possible combinations─too many, she says, for the elevator's computer to process in split seconds.

对于克里斯蒂来说，这些数学问题，没有唯一的最佳方案。在电梯的实际应用中有如此多的变量和组合，只要下一个人按下按钮，一切都会改变。在一个拥有六部电梯的大楼里，10个人想要在不同的楼层上下，就会产生超过6,000万种组合──她说，这太庞大了，电梯的电脑根本无法在瞬间对这些组合进行处理。

'We are constantly seeking the magic balance,' says the Wellesley math major. 'Sometimes what is good for the individual person isn't good for the rest.'

克里斯蒂毕业于美国韦尔斯利威尔斯利学院(Wellesley College)数学专业。她说，我们在不断寻找最佳平衡点。有时，对一个人有利的事未必对其他人有利。

A named inventor on 14 patents, Ms. Christy has a few more pending. She refers to the latest of them as the 'surfboard feature.' The idea came from a joke with colleagues when they were leaving one night after a dinner out. They sheepishly worried whether someday elevators might display a rider's weight. (Elevators already calculate the total weight in the car.)

克里斯蒂有14项以其名字命名的专利，目前还有几项专利正在申请。她提到其中最新一项是“冲浪板功能。其灵感来自与同事开的玩笑。一天晚上他们大吃一顿后正准备离开时，傻乎乎地担心会不会有一天电梯会显示乘客的体重。(现在的电梯已能计算轿厢内的总重量。)

The joke got Ms. Christy thinking of a feature that would allow people with a bulky or heavy item to have a car to themselves. So she and her colleagues created a system that can be programmed to allocate an empty car to a user. The feature would give users like hotel bellhops a numeric code that is punched in before entering the elevator. (A hotel in Hawaii considered using it to prevent surfers from disturbing other guests with their surfboards─hence its name.) The feature is generally used now by staff in hotels and office buildings.

这个玩笑让克里斯蒂想到了一个功能，可让携带庞大或沉重物体的人们单独乘梯。于是她和同事们发明了一个可设定程序给用户分配空轿厢的系统。该系统会给像酒店行李员这样的用户一个数字代码，他们进入电梯之前输入代码。(夏威夷某酒店曾考虑使用这个系统，这样的话拿着冲浪板的客人坐电梯就不会妨碍到其他客人，该发明也因此得名。)目前使用这一功能的一般是酒店和写字楼员工。

One part of Ms. Christy's career didn't go as planned. With aspirations of getting into management, Ms. Christy got her M.B.A. from Babson College, but the role didn't suit her. 'I thought I wanted to be a manager,' she said. 'But I really like solving the puzzles myself. I didn't like assigning them to other people. I was a little jealous.'

克里斯蒂的职业生涯也并非一切按部就班。当时一心想进公司管理层的她获得了美国巴布森学院(Babson College)的MBA学位，但管理者这一角色并不适合她。克里斯蒂说，我以为我想当管理者，但我真正喜欢的是亲自动手去解决难题，而不喜欢把工作安排给别人，我会有点羡慕他们。