将图片转换为视频

试了好几种方法,娘的,不容易啊
1,GIMP,可以导出gif格式
2,gThumb 先批量缩图,再转png格式为jpeg格式
3,stopmotion 不好使,导入很快,导出不知道为啥不行
4,直接用mencoder 命令,很快很方便
sudo apt-get install mencoder
mencoder mf://*.jpeg -mf w=800:h=600:fps=10:type=jpeg -ovc lavc -lavcopts vcodec=mpeg4:mbd=2:trell -oac copy -o 123.avi

谁知道还有啥linux下的方便的转换软件,png批量转gif或是avi的。

发表在 资料备份 | 标签为 | 3条评论

OpneOffice.Org公式编辑器语法命令

是要比MS的公式编辑器好用不少,恩

http://marsyan.ycool.com/post.1692991.html

http://hi.baidu.com/motioo/blog/item/8a7ba2edf0e48a4c79f05560.html

发表在 资料备份 | 标签为 | 一条评论

福岛反应堆事件的分析——转载

MIT 的这位老兄分析的还是比较靠谱的,有点长,耐心看看吧。

*********************************************
This post is by Dr Josef Oehmen, a research scientist at MIT, in Boston.

He is a PhD Scientist, whose father has extensive experience in Germany’s nuclear industry. I asked him to write this information to my family in Australia, who were being made sick with worry by the media reports coming from Japan. I am republishing it with his permission.

It is a few hours old, so if any information is out of date, blame me for the delay in getting it published.

This is his text in full and unedited. It is very long, so get comfy.

Why I am not worried about Japan’s nuclear reactors – Josef Oehman

I am writing this text (Mar 12) to give you some peace of mind regarding some of the troubles in Japan, that is the safety of Japan’s nuclear reactors. Up front, the situation is serious, but under control. And this text is long! But you will know more about nuclear power plants after reading it than all journalists on this planet put together.

There was and will *not* be any significant release of radioactivity.

By “significant” I mean a level of radiation of more than what you would receive on – say – a long distance flight, or drinking a glass of beer that comes from certain areas with high levels of natural background radiation.

I have been reading every news release on the incident since the earthquake. There has not been one single (!) report that was accurate and free of errors (and part of that problem is also a weakness in the Japanese crisis communication). By “not free of errors” I do not refer to tendentious anti-nuclear journalism – that is quite normal these days. By “not free of errors” I mean blatant errors regarding physics and natural law, as well as gross misinterpretation of facts, due to an obvious lack of fundamental and basic understanding of the way nuclear reactors are build and operated. I have read a 3 page report on CNN where every single paragraph contained an error.

We will have to cover some fundamentals, before we get into what is going on.

Construction of the Fukushima nuclear power plants

The plants at Fukushima are so called Boiling Water Reactors, or BWR for short. Boiling Water Reactors are similar to a pressure cooker. The nuclear fuel heats water, the water boils and creates steam, the steam then drives turbines that create the electricity, and the steam is then cooled and condensed back to water, and the water send back to be heated by the nuclear fuel. The pressure cooker operates at about 250 °C.

The nuclear fuel is uranium oxide. Uranium oxide is a ceramic with a very high melting point of about 3000 °C. The fuel is manufactured in pellets (think little cylinders the size of Lego bricks). Those pieces are then put into a long tube made of Zircaloy with a melting point of 2200 °C, and sealed tight. The assembly is called a fuel rod. These fuel rods are then put together to form larger packages, and a number of these packages are then put into the reactor. All these packages together are referred to as “the core”.

The Zircaloy casing is the first containment. It separates the radioactive fuel from the rest of the world.

The core is then placed in the “pressure vessels”. That is the pressure cooker we talked about before. The pressure vessels is the second containment. This is one sturdy piece of a pot, designed to safely contain the core for temperatures several hundred °C. That covers the scenarios where cooling can be restored at some point.

The entire “hardware” of the nuclear reactor – the pressure vessel and all pipes, pumps, coolant (water) reserves, are then encased in the third containment. The third containment is a hermetically (air tight) sealed, very thick bubble of the strongest steel and concrete. The third containment is designed, built and tested for one single purpose: To contain, indefinitely, a complete core meltdown. For that purpose, a large and thick concrete basin is cast under the pressure vessel (the second containment), all inside the third containment. This is the so-called “core catcher”. If the core melts and the pressure vessel bursts (and eventually melts), it will catch the molten fuel and everything else. It is typically built in such a way that the nuclear fuel will be spread out, so it can cool down.

This third containment is then surrounded by the reactor building. The reactor building is an outer shell that is supposed to keep the weather out, but nothing in. (this is the part that was damaged in the explosion, but more to that later).

Fundamentals of nuclear reactions

The uranium fuel generates heat by nuclear fission. Big uranium atoms are split into smaller atoms. That generates heat plus neutrons (one of the particles that forms an atom). When the neutron hits another uranium atom, that splits, generating more neutrons and so on. That is called the nuclear chain reaction.

Now, just packing a lot of fuel rods next to each other would quickly lead to overheating and after about 45 minutes to a melting of the fuel rods. It is worth mentioning at this point that the nuclear fuel in a reactor can *never* cause a nuclear explosion the type of a nuclear bomb. Building a nuclear bomb is actually quite difficult (ask Iran). In Chernobyl, the explosion was caused by excessive pressure buildup, hydrogen explosion and rupture of all containments, propelling molten core material into the environment (a “dirty bomb”). Why that did not and will not happen in Japan, further below.

In order to control the nuclear chain reaction, the reactor operators use so-called “control rods”. The control rods absorb the neutrons and kill the chain reaction instantaneously. A nuclear reactor is built in such a way, that when operating normally, you take out all the control rods. The coolant water then takes away the heat (and converts it into steam and electricity) at the same rate as the core produces it. And you have a lot of leeway around the standard operating point of 250°C.

The challenge is that after inserting the rods and stopping the chain reaction, the core still keeps producing heat. The uranium “stopped” the chain reaction. But a number of intermediate radioactive elements are created by the uranium during its fission process, most notably Cesium and Iodine isotopes, i.e. radioactive versions of these elements that will eventually split up into smaller atoms and not be radioactive anymore. Those elements keep decaying and producing heat. Because they are not regenerated any longer from the uranium (the uranium stopped decaying after the control rods were put in), they get less and less, and so the core cools down over a matter of days, until those intermediate radioactive elements are used up.

This residual heat is causing the headaches right now.

So the first “type” of radioactive material is the uranium in the fuel rods, plus the intermediate radioactive elements that the uranium splits into, also inside the fuel rod (Cesium and Iodine).

There is a second type of radioactive material created, outside the fuel rods. The big main difference up front: Those radioactive materials have a very short half-life, that means that they decay very fast and split into non-radioactive materials. By fast I mean seconds. So if these radioactive materials are released into the environment, yes, radioactivity was released, but no, it is not dangerous, at all. Why? By the time you spelled “R-A-D-I-O-N-U-C-L-I-D-E”, they will be harmless, because they will have split up into non radioactive elements. Those radioactive elements are N-16, the radioactive isotope (or version) of nitrogen (air). The others are noble gases such as Argon. But where do they come from? When the uranium splits, it generates a neutron (see above). Most of these neutrons will hit other uranium atoms and keep the nuclear chain reaction going. But some will leave the fuel rod and hit the water molecules, or the air that is in the water. Then, a non-radioactive element can “capture” the neutron. It becomes radioactive. As described above, it will quickly (seconds) get rid again of the neutron to return to its former beautiful self.

This second “type” of radiation is very important when we talk about the radioactivity being released into the environment later on.

What happened at Fukushima

I will try to summarize the main facts. The earthquake that hit Japan was 5 times more powerful than the worst earthquake the nuclear power plant was built for (the Richter scale works logarithmically; the difference between the 8.2 that the plants were built for and the 8.9 that happened is 5 times, not 0.7). So the first hooray for Japanese engineering, everything held up.

When the earthquake hit with 8.9, the nuclear reactors all went into automatic shutdown. Within seconds after the earthquake started, the control rods had been inserted into the core and nuclear chain reaction of the uranium stopped. Now, the cooling system has to carry away the residual heat. The residual heat load is about 3% of the heat load under normal operating conditions.

The earthquake destroyed the external power supply of the nuclear reactor. That is one of the most serious accidents for a nuclear power plant, and accordingly, a “plant black out” receives a lot of attention when designing backup systems. The power is needed to keep the coolant pumps working. Since the power plant had been shut down, it cannot produce any electricity by itself any more.

Things were going well for an hour. One set of multiple sets of emergency Diesel power generators kicked in and provided the electricity that was needed. Then the Tsunami came, much bigger than people had expected when building the power plant (see above, factor 7). The tsunami took out all multiple sets of backup Diesel generators.

When designing a nuclear power plant, engineers follow a philosophy called “Defense of Depth”. That means that you first build everything to withstand the worst catastrophe you can imagine, and then design the plant in such a way that it can still handle one system failure (that you thought could never happen) after the other. A tsunami taking out all backup power in one swift strike is such a scenario. The last line of defense is putting everything into the third containment (see above), that will keep everything, whatever the mess, control rods in our out, core molten or not, inside the reactor.

When the diesel generators were gone, the reactor operators switched to emergency battery power. The batteries were designed as one of the backups to the backups, to provide power for cooling the core for 8 hours. And they did.

Within the 8 hours, another power source had to be found and connected to the power plant. The power grid was down due to the earthquake. The diesel generators were destroyed by the tsunami. So mobile diesel generators were trucked in.

This is where things started to go seriously wrong. The external power generators could not be connected to the power plant (the plugs did not fit). So after the batteries ran out, the residual heat could not be carried away any more.

At this point the plant operators begin to follow emergency procedures that are in place for a “loss of cooling event”. It is again a step along the “Depth of Defense” lines. The power to the cooling systems should never have failed completely, but it did, so they “retreat” to the next line of defense. All of this, however shocking it seems to us, is part of the day-to-day training you go through as an operator, right through to managing a core meltdown.

It was at this stage that people started to talk about core meltdown. Because at the end of the day, if cooling cannot be restored, the core will eventually melt (after hours or days), and the last line of defense, the core catcher and third containment, would come into play.

But the goal at this stage was to manage the core while it was heating up, and ensure that the first containment (the Zircaloy tubes that contains the nuclear fuel), as well as the second containment (our pressure cooker) remain intact and operational for as long as possible, to give the engineers time to fix the cooling systems.

Because cooling the core is such a big deal, the reactor has a number of cooling systems, each in multiple versions (the reactor water cleanup system, the decay heat removal, the reactor core isolating cooling, the standby liquid cooling system, and the emergency core cooling system). Which one failed when or did not fail is not clear at this point in time.

So imagine our pressure cooker on the stove, heat on low, but on. The operators use whatever cooling system capacity they have to get rid of as much heat as possible, but the pressure starts building up. The priority now is to maintain integrity of the first containment (keep temperature of the fuel rods below 2200°C), as well as the second containment, the pressure cooker. In order to maintain integrity of the pressure cooker (the second containment), the pressure has to be released from time to time. Because the ability to do that in an emergency is so important, the reactor has 11 pressure release valves. The operators now started venting steam from time to time to control the pressure. The temperature at this stage was about 550°C.

This is when the reports about “radiation leakage” starting coming in. I believe I explained above why venting the steam is theoretically the same as releasing radiation into the environment, but why it was and is not dangerous. The radioactive nitrogen as well as the noble gases do not pose a threat to human health.

At some stage during this venting, the explosion occurred. The explosion took place outside of the third containment (our “last line of defense”), and the reactor building. Remember that the reactor building has no function in keeping the radioactivity contained. It is not entirely clear yet what has happened, but this is the likely scenario: The operators decided to vent the steam from the pressure vessel not directly into the environment, but into the space between the third containment and the reactor building (to give the radioactivity in the steam more time to subside). The problem is that at the high temperatures that the core had reached at this stage, water molecules can “disassociate” into oxygen and hydrogen – an explosive mixture. And it did explode, outside the third containment, damaging the reactor building around. It was that sort of explosion, but inside the pressure vessel (because it was badly designed and not managed properly by the operators) that lead to the explosion of Chernobyl. This was never a risk at Fukushima. The problem of hydrogen-oxygen formation is one of the biggies when you design a power plant (if you are not Soviet, that is), so the reactor is build and operated in a way it cannot happen inside the containment. It happened outside, which was not intended but a possible scenario and OK, because it did not pose a risk for the containment.

So the pressure was under control, as steam was vented. Now, if you keep boiling your pot, the problem is that the water level will keep falling and falling. The core is covered by several meters of water in order to allow for some time to pass (hours, days) before it gets exposed. Once the rods start to be exposed at the top, the exposed parts will reach the critical temperature of 2200 °C after about 45 minutes. This is when the first containment, the Zircaloy tube, would fail.

And this started to happen. The cooling could not be restored before there was some (very limited, but still) damage to the casing of some of the fuel. The nuclear material itself was still intact, but the surrounding Zircaloy shell had started melting. What happened now is that some of the byproducts of the uranium decay – radioactive Cesium and Iodine – started to mix with the steam. The big problem, uranium, was still under control, because the uranium oxide rods were good until 3000 °C. It is confirmed that a very small amount of Cesium and Iodine was measured in the steam that was released into the atmosphere.

It seems this was the “go signal” for a major plan B. The small amounts of Cesium that were measured told the operators that the first containment on one of the rods somewhere was about to give. The Plan A had been to restore one of the regular cooling systems to the core. Why that failed is unclear. One plausible explanation is that the tsunami also took away / polluted all the clean water needed for the regular cooling systems.

The water used in the cooling system is very clean, demineralized (like distilled) water. The reason to use pure water is the above mentioned activation by the neutrons from the Uranium: Pure water does not get activated much, so stays practically radioactive-free. Dirt or salt in the water will absorb the neutrons quicker, becoming more radioactive. This has no effect whatsoever on the core – it does not care what it is cooled by. But it makes life more difficult for the operators and mechanics when they have to deal with activated (i.e. slightly radioactive) water.

But Plan A had failed – cooling systems down or additional clean water unavailable – so Plan B came into effect. This is what it looks like happened:

In order to prevent a core meltdown, the operators started to use sea water to cool the core. I am not quite sure if they flooded our pressure cooker with it (the second containment), or if they flooded the third containment, immersing the pressure cooker. But that is not relevant for us.

The point is that the nuclear fuel has now been cooled down. Because the chain reaction has been stopped a long time ago, there is only very little residual heat being produced now. The large amount of cooling water that has been used is sufficient to take up that heat. Because it is a lot of water, the core does not produce sufficient heat any more to produce any significant pressure. Also, boric acid has been added to the seawater. Boric acid is “liquid control rod”. Whatever decay is still going on, the Boron will capture the neutrons and further speed up the cooling down of the core.

The plant came close to a core meltdown. Here is the worst-case scenario that was avoided: If the seawater could not have been used for treatment, the operators would have continued to vent the water steam to avoid pressure buildup. The third containment would then have been completely sealed to allow the core meltdown to happen without releasing radioactive material. After the meltdown, there would have been a waiting period for the intermediate radioactive materials to decay inside the reactor, and all radioactive particles to settle on a surface inside the containment. The cooling system would have been restored eventually, and the molten core cooled to a manageable temperature. The containment would have been cleaned up on the inside. Then a messy job of removing the molten core from the containment would have begun, packing the (now solid again) fuel bit by bit into transportation containers to be shipped to processing plants. Depending on the damage, the block of the plant would then either be repaired or dismantled.

Now, where does that leave us?

  • The plant is safe now and will stay safe.
  • Japan is looking at an INES Level 4 Accident: Nuclear accident with local consequences. That is bad for the company that owns the plant, but not for anyone else.
  • Some radiation was released when the pressure vessel was vented. All radioactive isotopes from the activated steam have gone (decayed). A very small amount of Cesium was released, as well as Iodine. If you were sitting on top of the plants’ chimney when they were venting, you should probably give up smoking to return to your former life expectancy. The Cesium and Iodine isotopes were carried out to the sea and will never be seen again.
  • There was some limited damage to the first containment. That means that some amounts of radioactive Cesium and Iodine will also be released into the cooling water, but no Uranium or other nasty stuff (the Uranium oxide does not “dissolve” in the water). There are facilities for treating the cooling water inside the third containment. The radioactive Cesium and Iodine will be removed there and eventually stored as radioactive waste in terminal storage.
  • The seawater used as cooling water will be activated to some degree. Because the control rods are fully inserted, the Uranium chain reaction is not happening. That means the “main” nuclear reaction is not happening, thus not contributing to the activation. The intermediate radioactive materials (Cesium and Iodine) are also almost gone at this stage, because the Uranium decay was stopped a long time ago. This further reduces the activation. The bottom line is that there will be some low level of activation of the seawater, which will also be removed by the treatment facilities.
  • The seawater will then be replaced over time with the “normal” cooling water
  • The reactor core will then be dismantled and transported to a processing facility, just like during a regular fuel change.
  • Fuel rods and the entire plant will be checked for potential damage. This will take about 4-5 years.
  • The safety systems on all Japanese plants will be upgraded to withstand a 9.0 earthquake and tsunami (or worse)
  • I believe the most significant problem will be a prolonged power shortage. About half of Japan’s nuclear reactors will probably have to be inspected, reducing the nation’s power generating capacity by 15%. This will probably be covered by running gas power plants that are usually only used for peak loads to cover some of the base load as well. That will increase your electricity bill, as well as lead to potential power shortages during peak demand, in Japan.

If you want to stay informed, please forget the usual media outlets and consult the following websites:

发表在 别人的口水 | 6条评论

一把年纪,居然又要开始学编程了

就从 vi 编辑器开始吧,先帖点命令,剩下的慢慢学

—————————————————-

1、vi的基本概念
基本上vi可以分为三种状态,分别是命令模式(command mode)、插入模式(Insert mode)和底行模式(last line mode),各模式的功能区分如下:

1) 命令行模式command mode)

控制屏幕光标的移动,字符、字或行的删除,移动复制某区段及进入Insert mode下,或者到 last line mode。

2) 插入模式(Insert mode)

只有在Insert mode下,才可以做文字输入,按「ESC」键可回到命令行模式。

3) 底行模式(last line mode)

将文件保存或退出vi,也可以设置编辑环境,如寻找字符串、列出行号……等。

 

不过一般我们在使用时把vi简化成两个模式,就是将底行模式(last line mode)也算入命令行模式command mode)。

2、vi的基本操作
a) 进入vi

在系统提示符号输入vi及文件名称后,就进入vi全屏幕编辑画面:

$ vi myfile
不过有一点要特别注意,就是您进入vi之后,是处于「命令行模式(command mode)」,您要切换到「插入模式(Insert mode)」才能够输入文字。初次使用vi的人都会想先用上下左右键移动光标,结果电脑一直哔哔叫,把自己气个半死,所以进入vi后,先不要乱动,转换到 「插入模式(Insert mode)」再说吧!

 

b) 切换至插入模式(Insert mode)编辑文件

在「命令行模式(command mode)」下按一下字母「i」就可以进入「插入模式(Insert mode)」,这时候你就可以开始输入文字了。

 

c) Insert 的切换

您目前处于「插入模式(Insert mode)」,您就只能一直输入文字,如果您发现输错了字!想用光标键往回移动,将该字删除,就要先按一下「ESC」键转到「命令行模式(command mode)」再删除文字。

 

d) 退出vi及保存文件

在「命令行模式(command mode)」下,按一下「:」冒号键进入「Last line mode」,例如:

: w filename (输入 「w filename」将文章以指定的文件名filename保存)

: wq (输入「wq」,存盘并退出vi)

: q! (输入q!, 不存盘强制退出vi)
3、命令行模式(command mode)功能键
1). 插入模式

按「i」切换进入插入模式「insert mode」,按”i”进入插入模式后是从光标当前位置开始输入文件;

按「a」进入插入模式后,是从目前光标所在位置的下一个位置开始输入文字;

按「o」进入插入模式后,是插入新的一行,从行首开始输入文字。

 

2). 从插入模式切换为命令行模式

按「ESC」键。

 

3). 移动光标

vi可以直接用键盘上的光标来上下左右移动,但正规的vi是用小写英文字母「h」、「j」、「k」、「l」,分别控制光标左、下、上、右移一格。

按「ctrl」+「b」:屏幕往”后”移动一页。

按「ctrl」+「f」:屏幕往”前”移动一页。

按「ctrl」+「u」:屏幕往”后”移动半页。

按「ctrl」+「d」:屏幕往”前”移动半页。

按数字「0」:移到文章的开头。

按「G」:移动到文章的最后。

按「$」:移动到光标所在行的”行尾”。

按「^」:移动到光标所在行的”行首”

按「w」:光标跳到下个字的开头

按「e」:光标跳到下个字的字尾

按「b」:光标回到上个字的开头

按「#l」:光标移到该行的第#个位置,如:5l,56l。

 

4). 删除文字

「x」:每按一次,删除光标所在位置的”后面”一个字符。

「#x」:例如,「6x」表示删除光标所在位置的”后面”6个字符。

「X」:大写的X,每按一次,删除光标所在位置的”前面”一个字符。

「#X」:例如,「20X」表示删除光标所在位置的”前面”20个字符。

「dd」:删除光标所在行。

「#dd」:从光标所在行开始删除#行

 

5). 复制

「yw」:将光标所在之处到字尾的字符复制到缓冲区中。

「#yw」:复制#个字到缓冲区

「yy」:复制光标所在行到缓冲区。

「#yy」:例如,「6yy」表示拷贝从光标所在的该行”往下数”6行文字。

「p」:将缓冲区内的字符贴到光标所在位置。注意:所有与”y”有关的复制命令都必须与”p”配合才能完成复制与粘贴功能。

 

6). 替换

「r」:替换光标所在处的字符。

「R」:替换光标所到之处的字符,直到按下「ESC」键为止。

 

7). 回复上一次操作

「u」:如果您误执行一个命令,可以马上按下「u」,回到上一个操作。按多次”u”可以执行多次回复。

 

8). 更改

「cw」:更改光标所在处的字到字尾处

「c#w」:例如,「c3w」表示更改3个字

 

9). 跳至指定的行

「ctrl」+「g」列出光标所在行的行号。

「#G」:例如,「15G」,表示移动光标至文章的第15行行首。

4、Last line mode下命令简介
在使用「last line mode」之前,请记住先按「ESC」键确定您已经处于「command mode」下后,再按「:」冒号即可进入「last line mode」。

A) 列出行号

「set nu」:输入「set nu」后,会在文件中的每一行前面列出行号。

B) 跳到文件中的某一行

「#」:「#」号表示一个数字,在冒号后输入一个数字,再按回车键就会跳到该行了,如输入数字15,再回车,就会跳到文章的第15行。

C) 查找字符

「/关键字」:先按「/」键,再输入您想寻找的字符,如果第一次找的关键字不是您想要的,可以一直按「n」会往后寻找到您要的关键字为止。

「?关键字」:先按「?」键,再输入您想寻找的字符,如果第一次找的关键字不是您想要的,可以一直按「n」会往前寻找到您要的关键字为止。

D) 保存文件

「w」:在冒号输入字母「w」就可以将文件保存起来。

E) 离开vi

「q」:按「q」就是退出,如果无法离开vi,可以在「q」后跟一个「!」强制离开vi。

「qw」:一般建议离开时,搭配「w」一起使用,这样在退出的时候还可以保存文件。

5、vi命令列表
1、下表列出命令模式下的一些键的功能:

h 左移光标一个字符

l 右移光标一个字符

k 光标上移一行

j 光标下移一行

^ 光标移动至行首

0 数字”0″,光标移至文章的开头

G 光标移至文章的最后

$ 光标移动至行尾

Ctrl+f 向前翻屏

Ctrl+b 向后翻屏

Ctrl+d 向前翻半屏

Ctrl+u 向后翻半屏

i 在光标位置前插入字符

a 在光标所在位置后一个字符开始增加

o 插入新的一行,从行首开始输入

ESC 从输入状态退至命令状态

x 删除光标后面的字符

#x 删除光标后的#个字符

X (大写X),删除光标前面的字符

#X 删除光标前面的#个字符

dd 删除光标所在的行

#dd 删除从光标所在行数的#行

yw 复制光标所在位置的一个字

#yw 复制光标所在位置的#个字

yy 复制光标所在位置的一行

#yy 复制从光标所在行数的#行

p 粘贴

u 取消操作

cw 更改光标所在位置的一个字

#cw 更改光标所在位置的#个字
2、下表列出行命令模式下的一些指令
w filename
储存正在编辑的文件为filename

wq filename
储存正在编辑的文件为filename,并退出vi

q!
放弃所有修改,退出vi

set nu
显示行号

/或?
查找,在/后输入要查找的内容

n
与/或?一起使用,如果查找的内容不是想要找的关键字,按n或向后(与/联用)或向前(与?联用)继续查找,直到找到为止。
对于第一次用vi,有几点注意要提醒一下:
1、 用vi打开文件后,是处于「命令行模式(command mode)」,您要切换到「插入模式(Insert mode)」才能够输入文字。切换方法:在「命令行模式(command mode)」下按一下字母「i」就可以进入「插入模式(Insert mode)」,这时候你就可以开始输入文字了。
2、编辑好后,需从插入模式切换为命令行模式才能对文件进行保存,切换方法:按「ESC」键。
3、保存并退出文件:在命令模式下输入:wq即可!(别忘了wq前面的:)

 

发表在 资料备份 | 10条评论

Hello world!

Welcome to WordPress.com. This is your first post. Edit or delete it and start blogging!

发表在 资料备份 | 一条评论

牛逼的德国大学

引文:《 德国大学与美国大学的对比》——(J.M.哈特著,靳贵珍译,李鹏飞校) 

和一哥们讨论该文,转载部分回信如下:(修正错别字若干。。。)

个人认为,德国大学上可以把一个”小混混”培养成做科研的人,

比如我打小就是个混的,和我一起长大的不是成了盗贼,就是做了出租车司机或者仓库管理员。丫的,一个小混混,去营房都(偷)防毒面具的小混混居然做科研了。你说,这德国大学牛逼不?
而美国大学更多的是把一个天长(才)培养成做科研的人,这不,
招收的全是中国的天长(才)精英。

于我心有戚戚焉。。。。。。。。。。

发表在 别人的口水 | 8条评论

开会开会

奥地利每年一次的winter seminar,每天早上presentation,下午滑雪。屁股摔成八瓣儿,有几次摔的东南西北都分不清了,后来初步掌握技巧,享受了好一阵速度与激情,最后下山的时候被逼无奈来了一把悬崖边急速过人,同事在后面激动的嗷嗷直叫,我吓出了一身冷汗,“刚才谁他妈的推我下去的!!?” 

周五刚从阿姆斯特丹回来,人家连个扫地的黑大爷都会英语,比我教授强。 城市很好,风挺大,老城区有的街名是中文,吓我一条。红灯区路过,没机会进店里看,觉得平时藏着掖着的东西这会满山遍野的铺开,有趣啊,下次找个机会看把table dance去。很喜欢这个城市,以后毕业了,可以考虑来这里工作,荷兰的核能研究所就在阿姆斯特丹旁边的一个小镇子上,面朝大海,春暖花开。

后面还有3个会,可惜只有9月份的在芬兰,剩下的两个都在德国。 想想,我这博士读的也值,欧洲已经快转了一圈。就算明天被开,我也能哼着小曲回到我们伟大祖国的怀抱了。

发表在 吃喝玩乐 | 7条评论