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Tue Jan 17 22:34:04 HKT 2017


log down some useful resource

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download zip of files only

Tue Feb 20 09:58:45 HKT 2018 From /weblog/science/animal


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Mon Feb 19 23:30:09 HKT 2018 From /weblog/computer+science


Bootstrapping a compiler from nothing. -


What LLVM can do, and cannot do -[..]er-behind-swift-rust-clang-and-more.html

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Mon Feb 19 23:26:54 HKT 2018 From /weblog/unix


Advisory Locking and Mandatory Locking -

Basic info of inode -

Explanation of /proc filesystem -[..]anual/ref-guide/s1-proc-directories.html

Linux file system structure -

File system for archive files -

BeOS file system, other than discuss about BeOS FS, also discussing about evolution of design of file system -[..]rce/news/2010/06/the-beos-filesystem.ars[..]03/past-present-future-file-systems.ars/


The file size of command "df" return is compressed data, raw disk usage
If we want compress amount, we need to get the compressratio using /usr/sbin/zfs
We can get more system detail via perl package Sun::Solaris::Kstat , we can google "" as an example

Using ZFS as version control -

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Sat Feb 17 23:44:47 HKT 2018 From /weblog/learning

Learn fast

#1 – Pegging (or How Mental Magicians can Perfectly Recall Hundreds of Numbers)
#2 – Metaphor (Juliet is the sun… or is she a chemical formula?)
#3 – Total Immersion (Or How a Guy Can Become Fluent in 8 Languages)
#4 – Visceralization (What does a derivative look like?)
#5 – Linking (Or How to Remember a Grocery List Without the Paper)
#6 – The 5-Year Old Method (Try explaining quantum physics to a first grader)
#7 – Ambiance Catalysts (Or How Drinking a Pint Can Improve Your Studying)
#8 – Diagrams (Who said doodling in class was wrong?)
#9 – Speed Reading (Or How to Read 70 Books in a Year)[..]ng-that-most-people-have-never-heard-of/

用 6 個步驟,熟悉一個產業 -[..]g-domain-expertise-in-a-complex-industry[..]-like-the-best-in-the-world-555fa4de5010[..].com/how-to-learn-anything-faster-2016-8

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Fri Feb 16 10:05:31 HKT 2018 From /weblog/learning


In other words, both groups were stressed, but one group channeled the stress as a performance challenge; the other group as a performance threat. It wasn't the stress of a difficult test that caused distress--everyone felt that. It was how subjects interpreted their stress. -[..]mbracing-stress-minimizing-distress.html

Calming when conflict -[..]ks-in-the-human-body-to-make-or-break-us

A Stanford psychologist has a simple mental exercise for tackling student stress -[..]l-exercise-for-tackling-student-anxiety/

The 40% rule is simple: When your mind is telling you that you’re done, that you’re exhausted, that you cannot possibly go any further, you’re only actually 40% done. ( umm... not sure if it really useful all the time ) -[..]the-40-rule-the-simple-secret-to-success

“The ideal situation for improving learning and memory would be to experience no stress and to exercise,” Edwards said. -

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Fri Feb 16 00:27:25 HKT 2018 From /weblog/learning


These 3 Hacks Will Make You Remember More -[..]will-make-you-remember-more-b30a3d9b3136

When trying to memorise new material, it’s easy to assume that the more work you put in, the better you will perform. Yet taking the occasional down time – to do literally nothing – may be exactly what you need. Just dim the lights, sit back, and enjoy 10-15 minutes of quiet contemplation, and you’ll find that your memory of the facts you have just learnt is far better than if you had attempted to use that moment more productively. -[..]effortless-way-to-strengthen-your-memory

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Sun Feb 11 23:34:31 HKT 2018 From /weblog/business


說一個好故事,讓 Pitch 更精彩 -

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Tue Feb 06 00:00:21 HKT 2018 From /weblog/database/performance

Note of SQL performance tuning

Note of this book -

1) Order of "and" and "or" is matter, if no cost-base optimizer

where column1 = 'a' and column2 = 'b' -> where column2 = 'b' and column1 = 'a' if column2 'b' is less likely

2) <> is more expensive than =

3) Can force to use index if SELECT * FROM table WHERE indexed_column > 0

4) UPPER(column) might lose information, use LOWER is better

5) WHERE column = 'WORD' or column = 'word' is always faster than WHERE LOWER(column) = 'word' , even faster version is test if database if case-insensitive: WHERE column = 'WORD' or ('WORD' <> 'word' AND column = 'word')

6) 32bit integer is the fastest datatype for 32bit OS

7) column in (?, ?) is faster than column =? or column = ? for some database, and don't slow in any database

8) For aggregate functions, prevent using having, try to use fewer columns in group by and use subquery if possible

9) In fact, count(1) is not faster than count(*)

10) CAST before aggregate function: SELECT CAST(SUM(column) AS INT) -> SELECT SUM(CAST(column as INT))

11) Use constant as much as possible, e.g.: select * from t1, t2 where t1.c1 = t2.c1 and t1.c1 = 1 -> select * from t1, t2 where t1.c1=1 andn t2.c1=1

12) Information of Join vs Subqueries

13) Information of optimum column type (VARCHAR, TIMESTAMP, WORD size INT and CHAR(1) usually better), shift effect for page

14) prevent NULL for porting issue

15) Low level table physical information

Some related links -[..]9/12/sql-optimization-tipsquestions.html

16) Prevent database level transaction, prevent joining, prevent locking ( like auto increment key ), pretty good suggestion -

17) Reduce dataset for aggregation -[..]-subqueries-to-count-distinct-50x-faster

Few good tips, like avoid cursors -[..]ent/21-rules-for-faster-sql-queries.html

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Mon Feb 05 18:14:08 HKT 2018 From /weblog/entertainment


Prince -[..]-the-artist-you-knew-as-prince/?view=all

elvis-presley -[..]ting-facts-about-elvis-presley/?view=all

george-michael -[..]-not-know-about-george-michael/?view=all

【傾聽音樂】中世紀音樂是宗教的奴僕,還是高貴的婢女 -[..]%98%E8%B2%B4%E7%9A%84%E5%A9%A2%E5%A5%B3/

不曾用西洋曲式寫流行曲的-創作歌手-朱頂鶴 -不曾用西洋曲式寫流行曲的-創作歌手-朱頂鶴/

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Fri Feb 02 10:19:00 HKT 2018 From /weblog/design/interview


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Tue Jan 30 14:16:18 HKT 2018 From /weblog/science


About PI -[..]i-%E6%98%AF%E6%B0%B8%E6%81%86-%E4%BA%8C/

Interesting maths -[..]-math-principles-to-challenge-your-brain

Napoleon was the Best General Ever, and the Math Proves it. -[..]ever-and-the-math-proves-it-86efed303eeb[..]al-math-tricks-that-will-blow-your-mind/

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Tue Jan 30 10:03:38 HKT 2018 From /weblog/trip/travelling


Travler pass -

Introduction of about how to figure out the public transport at Tokyo -

遊日別錯過:南阿爾卑斯, 橫跨山梨、長野、靜岡三縣的「南阿爾卑斯山脈」以及和福島縣的「只見」為新的生物圈保護區,其中別名為「赤石山脈」的「南阿爾卑斯山脈」風光如畫,山腳有溫泉景點,吸引不少遊客到此遠足或露營。 -[..]realtime/international/20140617/52582650

【岐阜】二訪世界文化遺產︰白川鄉的初夏極緻 -

平住東京3大文青旅館 $300 有找! -

日本的絕景秘境 -[..]%89%EF%BC%8F%E5%81%87%E6%89%8D%E5%AD%90/[..]%AD%EF%BC%8F%E5%81%87%E6%89%8D%E5%AD%90/

spectacular-railways -[..]railways-you-should-ride-before-you-die/

The “Venice of Japan” in Kyoto: a secret destination tourists don’t know about yet -[..]estination-tourists-dont-know-about-yet/

【日本世界遺產】日本人心中的TOP 10 你都去過了嗎? -

登上富士山,其實唔難 -[..]/forms/menutop/menutop.aspx?menu_id=1650

夏末東日本之旅(二)、新潟.白山 -[..]6%B0%E6%BD%9F%EF%BC%8E%E7%99%BD%E5%B1%B1

The best 50 things to do in Tokyo -[..]l-blog/the-best-50-things-to-do-in-tokyo

5 Must See Spots in Japan -[..]5862927717&blog=13214417&frame_type=none

National museum of nature and science, Tokyo -

八丈島 -


【東北溫泉】乳頭溫泉鄉 冬天不營業的秘湯

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Sat Jan 27 23:43:42 HKT 2018 From /weblog/misc


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Sat Jan 27 10:29:51 HKT 2018 From /weblog/security


A list of diagrams to show how TLS work

Understanding TLS protocol -- handshaking kickoff -
Understanding TLS protocol -- connection states -[..]rstanding_tls_protocol_connection_states
Understanding TLS protocol -- handshaking renew -[..]rstanding_tls_protocol_handshaking_renew
Understanding TLS protocol -- handshaking resume -[..]standing_tls_protocol_handshaking_resume

Another reading, about the handshaking for HTTP protocol -[..]/06/first-few-milliseconds-of-https.html

How to get HTTPs working -[..]nt-environment-in-5-minutes-7af615770eec

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Thu Jan 25 23:51:57 HKT 2018 From /weblog/java/fundamental


Pitfall and solution of implementing finalize(), if you really need it[..]ns_Boehm/misc_slides/java_finalizers.pdf

Optimization-robust finalization -[..]C1/SC22/WG21/docs/papers/2007/n2261.html

An example showing that memory leak caused by finalize() -[..]

Beware the Finalizer queue, and java.lang.ref.Finalizer object -

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Thu Jan 25 23:41:52 HKT 2018 From /weblog/finance


sources for equity quantitative research -[..]sources-for-equity-quantitative-research[..]com/2011/03/06/people-of-quant-research/[..]ive-strategy-development-process/150#150

Homepage of a guy using Haskell for Quant -[..]/2014/07/quantitative-resources-for.html

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Thu Jan 25 23:36:20 HKT 2018 From /weblog/science


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Thu Jan 25 00:36:20 HKT 2018 From /weblog/science/animal


about-search-and-rescue-dogs -[..]arch-and-rescue-dogs-youll-want-to-know/

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Wed Jan 24 15:45:50 HKT 2018 From /weblog/science


misconceptions -[..]-everyone-wants-you-to-believe/?view=all

Biology-mysteries -[..]manity-has-not-figured-out-yet/?view=all

Inventions -[..]-that-revolutionized-our-world/?view=all

Water -

River -[..]that-you-probably-did-not-know/?view=all

statistics-about-life-and-living -[..]atistics-about-life-and-living/?view=all

plants -[..]ique-plants-you-have-ever-seen/?view=all

time -[..]-mess-up-your-biological-clock/?view=all

Gold -[..]gold-that-might-just-amaze-you/?view=all

Colour -[..]lors-that-you-never-saw-coming/?view=all

Richard Feynman -[..]%8C%E4%B8%8D%E7%A2%BA%E5%AE%9A%E6%80%A7/

About palm-oil -[..]g-and-sad-facts-about-palm-oil/?view=all

How name related to face -

biggest-scientific-discoveries -[..]tific-discoveries-in-history-of-mankind/

weird-science-facts-you-may-not-know -

Diamond -

Why cloud don't fall -

michael-faraday -

【Gene 愛聊科學】食蟲植物讓獵物滑進瓶口的密技,成為對抗貽貝附著的無毒塗料:SLIPS -

The LeverAxe uses physics to finally bring splitting wood to the 21st century -

If virus alive?

Science of Mona Lisa -[..]eonardo-da-vinci-mona-lisa-smile/540636/[..]s/hidden-shortage-world-running-low-sand

What’s the difference between diffusion and osmosis -[..]ence/difference-diffusion-osmosis-043243

調查:「藍色星期一」最有生產力 -

Sound -

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Tue Jan 23 00:14:32 HKT 2018 From /weblog/trip


尋訪香港最好的茶餐廳 -

《米芝蓮港澳2013》 -[..]in2013/index.html?src=edm-ufood-20121219

寫在沙中線通車前幾年,我最喜愛的土瓜灣十間食肆 -[..]

速報:2018米芝蓮星級食店名單 -

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Tue Jan 23 00:10:23 HKT 2018 From /weblog/entertainment


讓我狠狠想你——王家衛電影的思念與愛情 -[..]%9D%E5%BF%B5%E8%88%87%E6%84%9B%E6%83%85/

十大最浪漫電影 -[..]A3%E5%B9%B4%E8%8F%AF-%E4%B8%8A%E6%A6%9C/

不按牌理出牌!影史10大即興演出 -[..]02/top-10-deadliest-horror-villains.html

歎為觀止的一鏡到底!影史著名12顆長鏡頭畫面 -

你是動作科幻迷嗎?影史40把知名槍械大集合! -

「我要打十個!」 回顧甄子丹7場精彩武打場面 -

喜劇之外:班史堤勒 -

中土世界的魔法師:彼得傑克森 -

Famous robots -

Robin Williams -[..]-actor-and-comedy-genius-robin-williams/[..]ilarious-stand-up-comedy-jokes-from.html

鈕承澤 -

Matrix -[..]hings-you-probably-didnt-know-about.html[..]/what-does-an-engineer-see-in-the-matrix

[專題] 從黑澤明的《七武士》淺談剪接在電影發展裡的奧祕 -

About Pulp Fiction -

Johnny Deep -

Inception -

Evolution of sound in movie -

聽到聲就知影!8 首知名角色登場配樂! -

[專題] 跟著老師動疵動!十部你不能錯過的歌舞電影 -

[專題] 最熟悉的陌生人:六位你一定要認識的電影片頭設計大師 -

傑克葛倫霍, Jake Gyllenhaal -

About "Back to the future" -[..]facts-you-probably-never-knew-about.html

Star war fact -[..]s-to-bring-out-your-inner-jedi/?view=all

Alan Rickman -[..]should-know-about-alan-rickman/?view=all

10 個不露骨卻讓人臉紅心跳的床戲-

[新聞] 亞洲電影大師之作!釜山國際影展評選出影史最佳亞洲電影前十名 -

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