SI vs. Gaussian units

This is a major source of confusion for many physics students, including me. The following link is an article that explains the differences quite clearly, citing some of the historical reasons for having two popular unit systems in use at the same time.

S.I. versus c.g.s. Units by Jason Harlow

Multi-threaded programming

This is something I've been curious about for a long time but haven't really had the chance to look into. Thanks to this tutorial at LLNL, I've discovered that it's actually quite easy to do simple multi-threading with POSIX threads -- all you really need are basic C programming skills and a basic concept of how processes are managed by a POSIX operating system. The API is easy to learn, and there is MUCH less overhead compared to multi-host parallel programming. On SMP machines, it is probably much more powerful than using a full parallel enviornment like MPI.

blunder blunder

一天之內連出兩個大包。

美國總統大選的通訊投票，忘記帶來新竹。

雙聖的晚餐，浪費掉了。

我好想哭。

---

後記：
晚餐很神奇的救了回來，感謝阿尼借的摩托車
歐巴馬先生，我的票寄出去了，加油！

研究所

來新竹一個月了。這學期修課總共十二學分，其中九學分包括恆星天文物理、電動力學和微波物理都很不容易拿。會讓自己負擔這麼重，一方面其實是給自己挑戰：我要是無法克服這邊的課程，之後就算成功申請出國一定也會水土不服；另一方面也是這些東西真的是有實用價值，不論是天文或是工程上都是很重要的知識。

除了最後兩年實驗室專題做的還不錯之外，我大學真的念得很糟。這是我一直不願意面對卻一直讓我非常沒自信，也阻礙我繼續求學的事情；因此來新竹之前就下定決心絕不能再像大學一樣把研究所搞砸。但最近卻越來越覺得奇怪—我以前大學到底是怎麼混過來的？也許是我現在課真的比較重，但最近一個月我每天我都覺得我大學從來沒真的讀過書；甚至現在用的讀書方法也都是在中研院當兩年助理培養出來的—這種感覺真的很糟，因為越來越覺得以前申請不到學校根本就是活該。也許這麼想有點過於激烈，但那種感覺的真實性毋庸置疑。

無論如何，我無疑的已經到了十字路口。堅持著理想不斷走下去，才有那麼一點機會能夠達成夢想。

Rings a bell

Loneliness is a terrible price to pay for independence.
                              --Anonymous

Not sure where I saw this, but I can REALLY identify with what it says.

Standard predefined macros

• From the GCC documentation:
  GCC Standard Predfined Macros
• A nice blog article
  

Came across this by accident today -- I guess I would've known about this stuff and saved a whole lot of trouble in the past year if I took a proper course in C programming. Oh well.

These are really useful macros for debugging and other purposes in writing C programs, for example the __FILE__ and __LINE__ macros will provide the location of a statement, and it is done completely automatically by the preprocessor, which saves a WHOLE lot of work for debugging -- exactly what SPARX needs.

Once again, RTFM...

安全背帶扣不安全

安全背帶扣有多安全？如果買到瑕疵品，那真的一點都不安全。就在剛剛，我的寶貝fender差點從我懷中摔到地上，因為應該要很安全的安全背帶扣竟然鬆脫了！


吉他的安全背帶扣，靠的就是圖中左手邊三個環狀的東西夾住背帶，再靠右手邊柱狀物的卡榫卡住吉他上的釘子。

結果柱狀物上的卡榫竟然縮進去了，真的是瑕疵品！有在用這玩意兒的人要小心呀！