FAQ


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翻译人:挪威的冬天、碧城仙、fwjmath。如有错误,敬请指正

1. General questions
1. 常规问题

1.1 What does LHC stand for?
1.1 LHC 是什么?

LHC stands for Large Hadron Collider. It will be the largest and most powerful particle accelerator ever built. You can read about it here.

LHC 是大型强子对撞机(Large Hadron Collider)的缩写。它将是有史以来最大也是最强的粒子加速器。点击这里了解相关信息。

1.2 What does LHC@home do?
1.2 LHC@home 能够做什么?

LHC@home helps the construction of LHC. It simulates how the particles travel trough the 27 km long tunnel. With the help of the calculated information, the magnets that control the beam can be calibrated with greater precision. More information can be found here.

LHC@home 能够帮助 LHC 的建设。它将模拟粒子如何穿越长达27公里的隧道。在计算得出的数据的帮助下,用以控制 beam 的 magnets 可以被提高到一个更高的精度。更多信息请看这里

1.3 Does it use my computer for anything else?
1.3 LHC@home 会用我的电脑做别的事情吗?

No. The computers of the participants are only used for this purpose.

不会。电脑将只被用来运算这个项目。

1.4 Server says out of work, why?
1.4 服务器总是显示没有新任务,这是为什么?

LHC@home calculations consist of many separate studies. Some studies can be started only after the previous have been analysed. We are doing our best to give out work at all times, but sometimes we just need to analyse old results before we can give out more. When this happens, please contribute to some other BOINC project(s) until we are able to submit new work. (Of course you can always participate to many BOINC projects simultaneously). You can find list of public BOINC projects here.

LHC@home 所进行的计算由许多被分割开来的任务构成。一些任务只有在前面的任务被解析之后才能开始进行。我们将尽全力的持续发布新的任务包,但有时候我们必须得在分析了之前回收的计算结果之后才能给出更多的新任务包。当发生这种情况时,请您为其它的 BOINC 运算项目贡献自己的力量直到我们可以给出新的任务包为止。(当然您可以一直同时运行多个 BOINC 项目)您可以在这里找到公共 BOINC 项目的列表。

2. Technical questions
2. 技术问题

2.1 What are the minimum requirements for the participating?
2.1 参与者计算机的最低配置要求?

The most important things are amount of RAM and disk space on your computer. Currently 60MB of free RAM and 30MB of free disk space is required before the server gives work to a computer. Deadline of work units is currently two weeks, so your computer must be fast enough to complete a work unit in this time. If your computer would be doing LHC@home calculation most of the time, any Pentium-class CPU or faster shoud do. However, if the BOINC client is running rarely or it is mostly used for some other projects, a faster CPU is needed.

最关键的因素是你计算机的内存容量大小与硬盘空间。一般在服务器向电脑传输任务前 60MB 的空闲内存与 30MB 的空闲磁盘容量是必须的。每一个任务的期限是 2 个礼拜,所以你的电脑需要具备一定的速度以保证在在这段时间内可以完成计算。如果你的电脑长时间运行 LHC@home 的话,那么任何 Pentium 级别或者更高的级别的处理器都是可以的。然而,如果 BOINC 客户端很少运行或者客户端大部分时间在运行其它项目的话,一颗更强劲的处理器是必须的(为了保证能在 2 个礼拜内完成一个任务)。

In short:
简而言之:

2.2 How long does one workunit last?
2.2 平均一个工作单元要分析多长时间?

This naturally depends on the speed of your computer. At the moment workunits may have different lengths. Some calculate 10,000 turns, others 100,000 turns and the rest calculate 1,000,000 turns around the accelerator. A job that calculates 1,000,000 turns will run approximately 10 hours on a 2 GHz processor.

这个主要是由您的计算机速度决定。同时工作单元的大小也会有所差异。有些需要模拟粒子绕加速环运行 10000 圈的情况,有的是 100000 圈,有的甚至达到 1000000 圈。一个需要计算 1000000 圈的工作单元在一个 2GHz 的处理器上需要花费大约 10 个小时。

2.3 Sometimes a workunit finishes in just a few minutes, why?
2.3 为什么有个别的工作单位(Work Unit)很快就算完了?

Some of the tested input data results in complete failure in the first loops. This is noted, and there is no sense to continue calculating the particles' orbits.

一些输入的测试数据在头几圈的模拟中就彻底地失败了。这种情况将被记录下来,并且没有必要再对于粒子的运行轨迹进行任何的计算。

We cannot know in advance which work units will fail short. These short jobs are just as important to us as the others.

我们无法事先得知哪些任务将在短时间内失败。但对于我们而言这些失败的任务与其它任务一样是十分重要的。

2.4 The graphics is slower on my computer when it runs as a screensaver than when I choose show graphics from boinc, why?
2.4 为什么在我的电脑上选择让 BOINC 显示模拟图像时,采用屏幕保护模式会很慢?

The speed of the graphics depend on the speed of the hardware. As a screensaver, the graphics run in full-screen, which takes more processing power than running it in a smaller window. Displaying the graphics might slow down the sixtrack calculations.

图像模式的显示速度取决于硬件本身的速度。屏保就好比让图像显示工作在全屏模式下,这将比窗口模式下消耗更多的计算资源。因此选择显示模拟图像可能会降低 SixTrack 的计算速度。

2.5 How and when do I get credit?
2.5 如何获得积分?

The new validator works like this:
新的验证规则如下:

2.6 When linux screen saver will be available?
2.6 linux 下的屏保程序何时发布?

When we find enough time to do it.

等到我们有足够的时间去忙它的时候。

2.7 Where should I report bugs/errors?
2.7 我应该到哪里去报告 bugs/errors?

The preferred ways of reporting bugs/errors is first to check if the bug already exists on the known bugs list, if not you should post the bug on a message board.

报告 bugs/errors 首选的方式是先到 known bugs list(已知 bugs 列表)中查看该 bug 是否已经被公布出来了,如果没有,请到 message board(留言板)发帖报告 bug。

2.8 Why is there no client for mac OS X / other OS?
2.8 为什么没有 mac OS X 或其他操作系统下的客户端?

Our Fortran compiler, which has seen to give the most reliable results, supports only Linux and Windows. So we can't make the client work on any other platform than these.

我们使用的是 Fortran 编译器,它能够让我们直观地看出最可靠的结果,但是仅仅只支持 Linux 和 Windows。所以我们无法提供其他平台下地客户端程序。

2.9 Why I get errors when uploading/downloading?
2.9 为什么我在上传或者下载的时候会出错误?

If you get errors like this:
SCHEDULER_REPLY::parse(): bad first tag Content-type: text/plain
Can't parse scheduler reply

Then the servers are most likely overloaded and cannot serve all connections.
This happens commonly after servers have been out of work for long time or after network / service breaks. Just be patient...

There are also other reasons causing download to fail. Some of those may be fixed by resetting your client, some may be server-related. Personal firewall software is also known to cause problems.

如果您得到的错误信息是这样的话:
SCHEDULER_REPLY::parse(): bad first tag Content-type: text/plain
Can't parse scheduler reply

那么很可能服务器过载了,不能对所有的连接进行响应。
这通常会在服务器长时间断线或者是长期没有任务以后发生,请保持耐心...

其他的因素有时候也会引起这个问题。有一些通过重设客户端就可以解决,有一些是由于服务器的关系。个人防火墙有时候也会导致这个问题。

3. The website
3. 网站

3.1 Why doesn't some pages seem to get updated (e.g. Top Users)?
3.1 为什么有一些页面好像没更新(比如说 Top User)?

Boinc caches the most common pages to reduce server load. The caching time is 12 hours, so the information is half day old at most.

为了减轻服务器负担,BOINC 对常用的页面进行了缓存,间隔时间是 12 小时,所以这些信息最多会迟 12 小时。

3.2 I signed up but did not receive an email, why not?
3.2 我注册了,但是收不到E-mail,为什么?

All our outgoing mail has to go through the main CERN queue, and some mailservers does not want to talk to ours. In some cases it can take up to several hours for these mails to arrive. Please be patient. If you have not received the mail within 24 hours then try again.

我们所有的邮件都要通过 CERN 的主要队列,并且有一些邮件服务器不愿跟我们联系上。某些情况下,邮件需要几个小时才能到达。请您耐心一点。如果您在 24 小时之内收不到邮件,请重试。

4. The Screen saver
4. 屏幕保护

4.1 What is this autopilot stuff?
4.1 什么是 Autopilot (自动导引程序)?

To assure that the graphics does not take to much time from the calculation we have included an autopilot in the screensaver. It reduces the number of particles and other settings to insure that at least a certain number of turns are calculated every second. You can still play around with the settings but after the autopilot timer runs out it will come back on and reduce the graphics workload. If you are not playing with it, it might as well calculate as fast as possible.

为了保证显示图形对计算程序的时间占用减到最小,我们在屏保中放置了一个自动导引程序。它可以减少显示的粒子束、改变各种设定,使每秒钟模拟的圈数至少达到一个确定的值。您仍然可以尝试调节设置,但是当自动导引程序每隔一段时间自动执行后,设定将会被改变以减少显示图形的负担。在您不去调节设置时,计算程序会尽可能快地计算。



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