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He said Russia will none-the-less continue to push for domestic energy efficiency and cuts in carbon emissions.
VOA: standard.2009.12.25
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And in practical terms, we can define the efficiency as the ratio of the heat in to the work out.
在实际中，我们定义,效率为热与功的比值。
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to put in place policies that incentivizes people to use things such as energy efficiency
他们制定了一些政策，鼓励人们使用能效高的产品，
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U.S.President Barack Obama has used his weekly address to encourage fiscal discipline in the federal government, and outline his plans to eliminate waste and increase efficiency.
VOA: standard.2009.04.25
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And so instead of defining efficiency the way you've got it written there, I'm going to define what's called something different for a refrigerator which is called the coefficient of performance.
现在我们不用,效率的那个定义，我给出一个,有关制冷机的,新的定义,叫做制冷系数。
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But the things we were trying to stress were that it's an important design decision when you are coming up with a piece of code, as to what kind of efficiency your code has.
但是我们这里要强调的是,当你写代码的时候,决定你的代码的效率的很重要的事情，就是你的设计决定。
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If the vehicle in the unfortunate circumstances of a collision, has to be able to maintain the security of the hydrogen which means more mass, which means a lot of the efficiency is being squandered What's the environmental impact of hydrogen production?
如果车辆,在碰撞中发生了不幸，要仍然能够保持氢气的安全性的话,意味着需要更多的质量，也就是说大部分效率被浪费了,制氢对环境有什么影响呢？
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And with respect to securities selection, you want to consider your skills and you want to consider the efficiency of markets when you're making your decisions as to whether or not to pursue passive management or active management.
证券选择方面,要考虑自身能力与市场有效性,从而决定,是采用被动型管理,还是主动型管理
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and how that relates to the efficiency of the market.
还有这个与市场效率有什么关系。
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As long as it's reversible, you know what the efficiency has to be, and in principle, you could break it down into a bunch of steps that you could formulate as isothermal and adiabatic.
只要这个循环过程是可逆的，你们知道效率是多少，从理论上说，可以将总过程,分解成一系列绝热,和等温的小过程。
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So what this says is the efficiency of any reversible engine T1 has to be one minus T2 over T1.
这就是说,任何可逆热机的效率都是,负T2除以。
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Now. It's a quick sidebar, I've got to say, I'm sure talking about efficiency to folks like you probably seems really strange.
这是个快速寻找的工具，我必须说跟你们讨论效率,看起来有点奇怪。
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And I just want to write those because what I really want to get at is what's the efficiency of the whole thing?
我写出这些的原因,是我真正想得到的是,它的效率？
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So we're not going to turn you into an expert on computational efficiency.
我们并不是要把你训练成,一个计算效率专家。
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Now, efficiency is obviously an important consideration when you're designing code, although I have to admit, at least for me, I usually want to at least start initially with code that works, and then worry about how I might go back and come up with more efficient implementation.
现在，当你设计程序的时候效率,是不得不考虑的问题，虽然我必须承认，至少对我来说,我是先担心程序能不能运行,再去把它的效率优化的,我喜欢可靠点的东西。
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But what we-- what we do want to do, is to give you some intuition about how to approach questions of efficiency.
但是我们想要你们产生，对于处理效率问题的一些直觉,你应该会意识到为什么。
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Now that already tells us what we know, which is that the efficiency is going to be something less than zero, right?
我们都知道这个，这结果就是说效率,是负的，对吗？
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I want to talk about efficiency, and we're going to, or at least I'm going to, at times also refer to this as orders of growth, for reasons that you'll see over the next few minutes.
为什么是很有价值的，我想要讨论下效率，我们将会，或者至少我将会不时的，提到有序的增长,原因你们很快就会明白的。
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So that efficiency is something less than one, and we'd like to figure out what that is.
因此效率肯定小于一，接下来解释这是为什么。
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And we want to help you learn how to map a problem into a class of algorithms of some efficiency That's our goal.
学会如何将一个问题,映射到一类,提升效率的算法中去,这就是我们的目标。
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If you could get to zero degrees Kelvin, you'd get perfect efficiency, 0 but you can't get to zero degrees Kelvin, you can't. Even if you have an infinite amount of resources, you can't get there.
如果能达到，你就能获得完美的效率，但你得不到，得不到，即使你有无穷多的资源,你也做不到。
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That in many cases, I can gain efficiency if I'm willing to give up space. Having said that though, there may still be a problem, or there ought to be a problem that may be bugging you slightly, which is how do I guarantee that my hash function takes any input into exactly one spot in the storage space?
普遍存在的增益和权衡,在许多的例子中,可以通过牺牲空间而得到效率方面的增加,话说回来，仍然存在一个问题,或者应该会有一个问题困扰着你,就是我如何保证我的哈希函数能够准确将,任一输入映射到相应的唯一的存贮空间中去？
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And the second thing that we talked about is this idea that we want you to in fact learn how to relate a choice you make about a piece of code to what the efficiency is going to be.
关于这个方法第二件事,就是我们实际上希望,你在写代码的时候,能做出优化效率的选择,因为此。
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All right, so you can't get perfect efficiency, 0 but at least if you were able to go to zero degrees Kelvin, then you'd be all set.
好吧，你得不到完美的效率，但至少如果能把温度降到,那你就万事俱备了。
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And then we're going to turn to the question of efficiency. How do we measure efficiency of algorithms? Which is going to be a really important thing that we want to deal with, and we'll start it today, it's undoubtedly going to take us a couple more lectures to finish it off.
然后我们会回头继续讨论效率问题,我们如何计算算法的效率？,我们处理这些问题的时候,最重要的事情是什么？,我们今天要去讨论这个问题，毫无疑问我们要用,挺多节课来学习这个。
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So what we want to do, is, I guess another way of saying it is, efficiency is really about choice of algorithm.
因此我们想做的就是，换种说法，效率实际上是算法的选择，我们想要培养你们。
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OK. So to do this, we need a little more abstract way of talking about efficiency, and so, the question is, how do we think about efficiency? Typically there's two things we want to measure.
好，为了达到这个目的,我们需要用一种有点，抽象的方式去讨论效率，这衍生出来,一个问题，我们该怎么去认识效率？,主要来说我们有两个要量化的东西。
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The closer the efficiency will get to one.
效率就越接近于一。
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I was going to start showing you some examples, but I think, rather than doing that, I'm going to stop here, I'm going to give you two minutes back of time, but I want to just point out to you that we are going to have fun next week, because I'm going to show you what in the world that has to do with efficiency.
我想再给你们讲解一些例子，但是我想想还是算了吧，给你们两分钟休息时间,但是我想告诉你们,我们下周的课,会很有意思,我会告诉你们,到底是什么决定了效率。
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As T2 goes to zero, the cold reservoir, then this goes to zero and our efficiency approaches one.
是当T2达到零，也就是低温热源，达到零度的时候,效率可以达到一。
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