英国皇家科学院圣诞讲座：让火花飞（2014）

让我们接入电源来看看吧
well, let's plug it in and find out.
我需要戴一下护目镜
So I'm just going to put some safety specs on here.
大家准备好了吗
Right, are we ready for this?
你们看到了吧
You see it.
它的确发光了 但很快就烧尽了
So it did glow but then very quickly it burnt out.
这是因为
And the reason it does that is
玻璃罩是保护灯丝的
the glass is protecting the filament.
灯丝周围充满了保护性气体
Because there's protecting gas around that filament,
阻止空气与灯丝接触
so it's not allowing the air to get to that filament.
一旦氧气接触灯丝
So once the oxygen gets to there,
灯丝就会很快烧尽
it burns out very quickly,
就像我们刚刚看到的一样
as we have just saw.
我们可以换种方法让它发光吗
But can we keep it glowing in another way?
安迪会来帮我演示
Well, Andy is going to help me with this,
我再把护目镜戴上
and I'm going to put my specs back on.
你好 安迪
Hi, Andy.
我们这里还有一个灯泡
So what we have is another bulb
它的玻璃罩被移除了
which has had the glass removed,
灯丝还在上面
so it still has our filament in there,
但没有玻璃罩了
the glass has been removed again.
安迪将要做的是
And what Andy is going to do is
在这个容器里倒满液氮
fill this container with liquid nitrogen.
液氮看上去总是很棒对吧
Liquid nitrogen always looks really good, doesn't it?
如果现在我把灯泡浸到
Right, so, if I now dip my light bulb
液氮里去
in the liquid nitrogen,
已经全部没入了
so it is completely covered...
然后我打开开关
And then I turn it on.
这会奏效吗
Is this going to work?
会吗 我们来看看
Yeah? Let's see.
奏效了
It works.
它不仅亮了 而且还一直发光
But not only does it light up, but it stays lit up as well.
这是因为
And the reason for that is
液氮一直让氧气远离灯丝
the liquid nitrogen is pushing the oxygen away from that filament.
这样氧气就不会围绕在金属周围
so the oxygen is not surrounding out of our metal any more,
使得灯丝可以持续发光
so it allows it to keep glowing.
很棒 非常感谢 安迪
Great. Thanks very much, Andy.
这些白炽灯泡的弊端是
Now, the problems with Swan's light bulbs are
会发热损失大量电能
they lose a lot of electric anergy as heat.
我们不是只需要一个灯泡
And we need not one light bulb.
我们需要182个灯泡
We need 182 light bulbs.
所以需要找些电能利用率更高的
So we needed something much more efficient.
我们将目光投向了LED灯
So we decided to look at LED bulbs.
虽其价格昂贵
They are still quite expensive
不过它们将电能转化为光能的
but they are much better at converting electrical energy
效率更高
to light energy,
因此LED灯能耗低 产热少
so they use much less power and they don't get as hot.
所以我们是这样做的
So that is what we did.
我们准备了182个LED灯
We got 182 LED bulbs,
每扇窗户配一个
one for every window.
现在 我们要确保能
Now, we needed to make sure that we could
看见窗户里的亮光
actually see that window glow.
我们利用烘焙纸
So we used some baking paper here
使光线在窗户上达到散射的效果
to diffuse the light in our windows.
我们还要确保光
Then we needed to make sure the light was directed
能透过窗户照到室外
away from the room and out of the window,
这样我们从外边才能看到
so out so we could see it from outside.
如你们所见 我们也在窗户上
So you can see here, we have used
挂了反射薄膜
some reflective film on our windows as well.
第一阶段 第一步做完了
So step one, part one, done.
我们只利用在本地DIY商店
We've managed to make every window pixel
买♥♥到的台灯灯座和LED灯
just by using desk lamps and LEDs
就使每扇窗户都变成了像素点
that we bought at the local DIY store.
不过窗户上的灯光和制♥作♥屏幕
But there is still a big difference between lights in windows
还是有很大区别的 不是吗
and making a screen, isn't it?
各位回想一下这里的小屏幕
If you think back to our small screen here,
这里有很多LED
we have lots of LEDs,
我们同样需要控制灯光的方法
but we also need ways of controlling all of those lights.
我们如何才能给每盏灯下指令呢
So how do we tell each lamp what to do?
在地面将几盏LED灯连在一起很容易
Well, it's easy just to wire a bunch of LED lights on the ground,
我们可以做到
we can do that,
但要放大应用到这幢摩天大楼
but it would be really really difficult to scale it up
就相当困难了
to what we need for our giant skyscraper here.
我知道你们在想什么
Now, I know what you are thinking,
大楼里已经铺设过网络了 对吧
while there are already wires in the building, are they?
当然 现在大家都会使用网络电缆
Surely everyone has got a network cable these days.
的确如此
And, the answer is yes,
这里的网络电缆
this has a network cable just the same as
跟你们在家里用的一样
the things that you guys will have at home.
就是传统的网线
Just an ethernet cable.
我们可以利用网络电缆
So, we could network all of our windows of lights
将所有窗旁的灯联网 对吧
just using network cables, couldn't we?
在回答这个问题之前
Well, before we answer that question,
我要向你们展示一些
I want to show you something really, really cool
与网络电缆有关的相当酷炫的东西
with network cables right here tonight.
如果有人看过电影《黑客帝国》
So if anyone has seen the Matrix film,
就会知道《黑客帝国》里有一个片段是
you know that part in the Matrix
时间静止
where the two actors freeze in time
两个演员悬浮在空中
and they are suspended in the air
他们跳起后
so they jump up in the air
时间静止
and they are frozen in time
摄影机围绕着他们拍摄
and the cameras pan around them.
想起来那个片段吗 还记得吗
You know that? Have you seen that before yet?
我们在这里情景重现一下
Well, let's try and recreate that here.
这里有40个树莓派构成的半圆
What we have here is a semicircle of 40 Raspberry Pis.
树莓派是一款基于Linux系统的 只有信♥用♥卡♥大小的单板机电脑
树莓派是一种小型嵌入式计算机
You know Raspberry Pis are just little embedded computers
你们当中肯定很多人用过
and I am sure many of you use them before.
如果我们再仔细观察一下
If we have a look a bit more detail here,
可以看见它顶部有一个小的液晶显示屏
we can see that it has a little LCD display on the top.
上面有一个摄像机
It has a camera
还插有网线
and it also has our ethernet cables,
所以是有线网络
so it is a wired network.
我们可以让这些照相机
So we can all use these cameras
在同一时刻拍照
to take photograph at exactly the same time
然后将获得的图像拼在一起
and then stitch all of that information together.
我们的电脑在这儿
So, our computer down here,
安德鲁就能
Andrew is going to be able to take,
在同一时间
we're gonna take the photographs
将这些照片拍下来
at exactly the same time
然后安德鲁来处理这些信息 好吗
so Andrew will trigger that information. OK?
现在 我们都看出来这里缺点东西
Now, we all've seen missing a couple of things here.
谁自告奋勇来跳一跳
Volunteers to be jumpers.
好的
OK, let's go.
那边的同学 请上台来
You there, please. Yes.
还有你
And you here.
很好 非常感谢
OK. Great. Thank you very much.
-你叫什么名字 -我叫艾兹
- All right. What's your name? - I'm Edz.
艾兹 好的 艾兹
Edz. OK, Edz.
我需要你站在 大致这个地方
I'd like you to stand, coming about here.
面对那个安全出口的标志好吗
And just face the Fire Exit sign over there, OK?
我觉得该再离远点
Coming a ittle bit further, I think.
得让你站在合适的位置
I just need to get you about right.
你叫什么名字
OK. What is your name?
-哈莉特 -好的 哈莉特
- Harriet. - Harriet. OK.
哈莉特 你只需面向观众席
Well, Harriet you just have to turn to where you are sitting
然后退到这里
and then just go backwards here
面对那边的安全出口
and then just face that Exit sign there. Right.
位置应该站对了 好
We should be good there. Right.
希望你们俩都能跳得很高
Hopefully you guys are good jumpers.
可以吗
Yeah?
你自告奋勇来的 哈莉特