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Sun Jul 23 22:00:11 HKT 2017



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Sun Jul 30 17:10:51 HKT 2017 From /weblog/unix

performance


Few config suggestions - http://blog.monitis.com[..]20-linux-server-performance-tips-part-2/

Linux kernel profiling with perf - https://perf.wiki.kernel.org/index.php/Tutorial http://lxr.free-electrons.com/source/tools/perf/design.txt

Intel VTune Amplifier profiler - http://software.intel.com/en-us/intel-vtune-amplifier-xe

Oracle solaris studio - http://www.oracle.com[..]torage/solarisstudio/overview/index.html

http://www.brendangregg.com/linuxperf.html <- "This page links to various Linux performance material I've created, including the tools maps on the right."

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Wed Jul 26 10:57:03 HKT 2017 From /weblog/database

time series


Some information about Time Series:

http://en.wikipedia.org/wiki/S-PLUS
http://download-west.oracle.com[..]ocs/cd/A87860_01/doc/inter.817/index.htm
http://www.sas.com/
http://oracledmt.blogspot.com/2006/10/time-series-revisited.html
http://oracledmt.blogspot.com[..]1/time-series-forecasting-part-1_23.html

Discussion of time in time series database - UTC or local - http://quant.stackexchange.com[..]ime-in-time-series-database-utc-or-local

Market data:
http://cs.nyu.edu/cs/faculty/shasha/fintime.html

and a book:
http://sql-info.de[..]iented-database-applications-in-sql.html
http://www.cs.arizona.edu/people/rts/tdbbook.pdf

Should we use DATE as key or INT as key? http://quant.stackexchange.com[..]senting-time-series-implementation-level

Collections of column-oriented stores - http://quant.stackexchange.com[..]s/1392/usage-of-nosql-storage-in-finance

时序数据库深入浅出之存储篇 - http://www.infoq.com/cn/articles/storage-in-sequential-databases

深入浅出时序数据库之压缩篇 - http://www.infoq.com/cn/articles/condense-in-sequential-databases

pretreatment - http://www.infoq.com[..]les/pretreatment-in-sequential-databases

Why - http://www.infoq.com/cn/news/2017/07/Why-time-series-database

分级存储 - http://www.infoq.com[..]archical-storage-of-sequential-databases

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Wed Jul 26 10:20:22 HKT 2017 From /weblog/web

performance


One of many tips of how to design a website that deliver content faster - http://alexander.kirk.at[..]006/02/02/10-steps-to-a-faster-web-site/

The other, for user to read quick - http://www.vandelaydesign.com[..]0-ways-to-design-for-impatient-visitors/

Webmaster tools, marketing - http://www.sitepronews.com/archives/2007/aug/3.html
Webmaster tools, page development - http://manwithnoblog.com/2007/08/05/css-debugging-tools/
and tools to tune page performance - http://skytechgeek.com[..]tools-to-boost-up-your-site-performance/

Tips from codinghorror - http://www.codinghorror.com[..]og/2011/06/performance-is-a-feature.html

Tips from ACM - http://queue.acm.org/detail.cfm?ref=rss&id=2512489

Web Framework Benchmarks - http://www.techempower.com/benchmarks/

How taobao optimize their mobile app - http://www.infoq.com[..]bao-521-performance-optimization-project

The timeline of how browser showing the page, and how to optimize it - http://www.nateberkopec.com[..]rontend-performance-chrome-timeline.html https://medium.com[..]-for-the-browser-f2f51a29c572#.7ivccwl5e

How a page loaded fast - https://varvy.com/pagespeed/wicked-fast.html https://medium.baqend.com[..]d-page-loads-lessons-learned-4bb1be3ed07

About making picture load faster - http://www.infoq.com[..]icles/yelp-lossless-compression-pictures

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Tue Jul 25 11:18:11 HKT 2017 From /weblog/trip/travelling

south america


阿根廷的觀鳥天堂 - http://cn.wsj.com/big5/20120510/trv081838.asp

http://thenatureoftheworlds.blogspot.com.au[..]m.au/2013/10/iguazu-falls-argentina.html

magnificent-torres-del-paine-national-park-photos-you-absolutely-have-to-see - http://list25.com[..]tos-you-absolutely-have-to-see/?view=all

Hotel next to Perito Moreno Glacier - http://www.eolo.com.ar/home_eng.htm

一個中國人在沒有馬奎斯的波哥大- https://theinitium.com[..]0170211-culture-travel-marquez-columbia/

世界獨一無二 哥倫比亞彩虹河奇觀 - https://dq.yam.com/post.php?id=2498

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Tue Jul 25 00:48:50 HKT 2017 From /weblog/science

light


Interesting, test speed of light with ping - http://physics.stackexchange.com[..]experiments-to-derive-the-speed-of-light

History of color photograph - http://writescience.wordpress.com/2012/11/21/in-living-color/

光電效應:愛因斯坦的諾貝爾 - https://phycat.wordpress.com[..]19/photoelectric-effect-einsteins-nobel/

光速:宇宙高速公路的速度限制 - https://phycat.wordpress.com/2016/12/08/speed-of-light/

What exactly is a photon? Definition, properties, facts - http://www.zmescience.com/science/what-is-photon-definition-04322

Why Gold is yellow in color - http://www.zmescience.com[..]other/feature-post/gold-color-relativity

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Fri Jul 21 17:24:58 HKT 2017 From /weblog/database/performance

Note of SQL performance tuning


Note of this book - http://www.ocelot.ca/tuning.htm

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 - http://www.techartifact.com[..]9/12/sql-optimization-tipsquestions.html

16) Prevent database level transaction, prevent joining, prevent locking ( like auto increment key ), pretty good suggestion - http://www.aviransplace.com/2015/08/12/mysql-is-a-great-nosql/

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

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Wed Jul 19 17:07:17 HKT 2017 From /weblog/political

democracy


Problem?? http://cn.wsj.com/big5/20110419/GOK075032.asp?source=rss

民主、法治與自由 - http://cn.wsj.com/big5/20111010/WES071154.asp?source=rss

憲政與民主:孰先孰後? http://cn.wsj.com/big5/20130131/YXZ070844.asp?source=rss

Noam Chomsky - http://list25.com/25-facts-about-noam-chomsky/?view=all

從思考終審法院的多數決制度我們能學到什麼? -
https://thestandnews.com[..]%BD%E5%AD%B8%E5%88%B0%E4%BB%80%E9%BA%BC/

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Wed Jul 19 14:59:51 HKT 2017 From /weblog/design

packaging


Avoid circular dependencies between packages! http://www.infoq.com/news/2007/06/large-code-bases

2 common approach, by function or by layer - http://dolszewski.com/architecture/project-package-organization/

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Wed Jul 19 00:22:53 HKT 2017 From /weblog/security

tools


The NSA has open-sourced dozens of security tools
- https://medium.freecodecamp.org[..]ced-dozens-of-security-tools-7af99cfe422

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Tue Jul 18 23:56:58 HKT 2017 From /weblog/learning

performance


焦慮能讓你表現更出眾 - http://cn.wsj.com/big5/20120711/hea075016.asp?source=rss

Importance of finding out your Signature Strengths - http://traderfeed.blogspot.com.au[..]ature-strengths-and-trading-success.html

索托說:“你應該從改變行為做起,接下來,如果你能長期保持這種新行為,這種行為就會被鎖定下來。”他說,如果能獲得心理治療師的指導,你可以在幾個月之內看到持續的變化。你也可以學著自己管理你的性格特征,只是要花費比較長的時間。
那么,你應該從哪做起呢?加州德爾馬(Del Mar)的心理學家理查德‧萊瓦克(Richard Levak)表示:“首先,我們必須認識到性格中有哪些因素對我們構成了影響。如果我愛發牢騷,好爭辯,還有點多疑,我總是因為跟同事吵架,老是責怪別人而被解雇,那我就必須意識到得改變一下。”
萊瓦克說,這和糾正暴飲暴食這種壞習慣相似。要想減肥,你就得認識到自己什么時候以及為什么會暴飲暴食。萊瓦克博士表示:“如果你有戒心過重和好斗的傾向,你就要對自己說:‘好的,當我老板過來跟我說話,而我立馬感覺老板在挑我的刺,想要自我防衛的話,那我就是反應過激了。’讓自己冷靜下來,不要爭吵。”
不要把期望值定得太高。耐心一些。索托博士說,要把一種有意為之的行為變成習慣,需要花費很長時間。不要太擔心其他人的反應,因為你的變化通常是他們樂于見到的。

http://cn.wsj.com/big5/20140502/lif114051.asp?source=rss

How you can use your negative emotion - http://www.theatlantic.com[..]reat-depression/304247/?single_page=true

Performance improvements… or experiments? - http://letstalkaboutjava.blogspot.com[..]ormance-improvements-or-experiments.html

http://traderfeed.blogspot.hk[..]e-you-operating-in-peak-performance.html

This, I find, is the single greatest impediment to pursuit of excellence: Most of us are simply too busy doing our jobs well to become truly world class at what we do. I occasionally ask traders to go back to old journal entries and tell me how much time they spent reviewing those entries and assessing their progress over the past week. In the great majority of instances, the journal entries are never revisited! - http://www.forbes.com[..]ndar-into-a-peak-performance-tool/print/

10-questions-can-dramatically-change-life and business (I don't think so, but anyway a good reading) - https://thenextweb.com[..]ns-can-dramatically-change-life-business

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Tue Jul 18 00:30:55 HKT 2017 From /weblog/learning

presentation


How to capture the attention from audience in 30 second - http://www.learninggeneralist.com[..]tter-beginnings-how-to-capture-your.html

How you can build Meaningful Interactivity into your eLearning - http://www.learninggeneralist.com[..]010/01/how-you-can-build-meaningful.html

3 Ways to Spice up Linear Navigation in Elearning - http://www.learninggeneralist.com[..]ys-to-spice-up-linear-navigation-in.html

5 Simple Ideas to Avoid Presentation Nervousness - http://www.learninggeneralist.com[..]-simple-ideas-to-avoid-presentation.html

3 Visual Design tips to make your presentation slides pop - http://www.learninggeneralist.com[..]4/3-visual-design-tips-to-make-your.html

Questions to ask to make presentation short - http://www.stevenlist.com[..]blog/2011/03/29/make-a-long-story-short/

Some tips for developing presentation skill - http://www.insightfullogic.com[..]w-grow-speakers-your-technical-community

做個一流講者 - http://wired.tw/posts/2789

Ignite, a way of short presentation - http://blogs.ancestry.com/techroots/ignite-at-ancestry-com/

http://www.bbc.com[..]s-to-make-yourself-effortlessly-charming

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Thu Jul 13 00:26:12 HKT 2017 From /weblog/trip/travelling

German


The trip of art - http://cn.wsj.com/big5/20120203/trv083545.asp?source=rss

History when communist party in charge - http://cn.wsj.com/big5/20121221/LLW075021.asp?source=rss

柏林圍牆的去或留 - http://thisbigcity.net/zh-hant/berlinwall/

http://blog.kkday.com/2017/06/reasons-to-visit-berlin.html

通往神秘世界的入口?德國完美倒影魔鬼橋 - http://www.dcfever.com/travel/deal.php?id=19686 http://mymodernmet.com/circle-bridge-photography/

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Wed Jul 12 14:46:08 HKT 2017 From /weblog/photographic

star


星軌拍攝技巧 數問 -

1).數碼機因hot pixel而唔適合曝得耐...最好分開影影夠幾個鐘...咁每張間隔之間都要俾CMOS斗下氣?
有師兄 教過 分十幾張 每張 10-20min 再合成 好過 一野 暴 幾粒鐘, (菲林 令計)

2).數碼機有D人話用ISO 100、有人話用ISO 400-800好...如果用合成方法...其實係咪都係就番光害而定...定係關雜訊事?
睇天氣 , 小弟 用 o個次 用 iso 100

5).北極星仰角澳門係23度,咁香港一樣??
4季 都唔同 位置, 用星座 搵 會準確 d, e+ 係 冬季, 北極星 位置 係 獵戶座 (lei 個最易 認, 唔會 搵唔倒 ... ) 頭頂 (腰帶 致 頭頂 距離 再過 5倍左右)

附圖 係 舊年 去雲南 香格里拉 時影, 本泥想 長暴, 不過 o個晚 太涷 個人 頂唔順 要收皮 反酒店

http://www.dchome.net/viewthread.php?tid=798154

With a lot of information, 香港的星空 — 觀測及拍攝資訊 - http://www.dcfever.com/column/read.php?id=1829

Herman's articles at dcfever - http://www.dcfever.com/column/info.php?id=185

500px tutorial - http://500px.com/blog/738/tutorial-photograph-the-night-sky

About Comet - http://www.dcfever.com/column/read.php?id=2193

Atmospheric optical phenomena 大氣光學現象 - http://matthew-chin.blogspot.hk[..]16/06/atmospheric-optical-phenomena.html

=====
這張是11月15日凌晨拍攝的M42獵戶座星雲, 大埔的光害較嚴重, 所以要加上IDAS V4濾鏡作長時間曝光, 分三段不同時間曝光及作Layer Masking 處理, 把動態範圍拉闊. 在月光的影下算是滿意, 希望之後可以分數晚作10小時以上的曝光並加長每一張frame 的曝光時間 (現在是5分鐘一張), 使到暗位的表現進一步改善.

Place: Tai Po
Date: 14 Nov, 2013 (UT)
Camera: Canon 20Da
Lens: Canon EF-600 F4L
Mount: Vixen Sphinx with Star Book
Filter: IDAS V4
Exposure: 10 sec x 10, 30 sec x 10, 300sec x 26
ISO: 800
Guiding: Borg 60mm telescope, AIS120MM, PHD guiding.
Image calibration: Dark x 20 (average) for each exposure, Bias x 16 (Median), Dark subtracted Flat field x 20 (Median)
Processing: DSS, PS: layer Mask, Cropped, curve, colour adjusted.

http://forum.hkas.org.hk/viewthread.php?tid=8009
=====

http://list25.com[..]resemble-things-found-on-earth/?view=all

how-to-find-the-milky-way - http://goldpaintphotography.com[..]om/2015/07/24/how-to-find-the-milky-way/

how-to-capture-sharp-star-photographs - http://www.mikkolagerstedt.com[..]10/how-to-capture-sharp-star-photographs

銀河 - 觀測和拍攝 - http://matthew-chin.blogspot.hk/2016/06/blog-post.html

簡易四步驟處理高清銀河 - http://www.dcfever.com/column/read.php?id=3278 TimeLapse-AfterEffects特效『星流跡影片』-進階 - http://www.dcfever.com/column/read.php?id=3935

500 rule:
11mm: 45.5 seconds
12mm: 41.7 seconds
14mm: 35.7 seconds
16mm: 31.3 seconds
18mm: 27.8 seconds
20mm: 25 seconds
24mm: 20.8 seconds
28mm: 17.9 seconds
35mm: 14.3 seconds
50mm: 10 seconds
85mm: 5.9 seconds

http://www.price.com.hk/news.php?sec_id=12&id=7216

How to find constellations: a starter’s guide - http://www.zmescience.com[..]eature-post/starter-guide-constellations

想拍漂亮的散景靜物嗎?6步驟DIY一個超絢麗散景牆, with 鋁箔或銀色包裝紙 - http://digiphoto.techbang.com[..]steps-to-a-super-gorgeous-diy-bokeh-wall

http://www.deepskycolors.com[..]ilky-Way-Photo-Concepts-You-May-Wan.html

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Wed Jul 05 11:27:44 HKT 2017 From /weblog/trip/travelling

Philippines


巴拉望 - http://go2nature.net[..]t=32342&postdays=0&postorder=asc&start=0 http://travel.sina.com.hk/news/121/4/1/27443/1.html http://blog.kkday.com/2016/11/PalawanSpots.html

cebu - http://blog.kkday.com/2017/07/cebutop10.html

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Tue Jul 04 00:36:50 HKT 2017 From /weblog/%E6%97%A5%E5%B8%B8%E7%94%9F%E6%B4%BB

food


寫在沙中線通車前幾年,我最喜愛的土瓜灣十間食肆 - http://foodie-smashingpumkins.blogspot.hk/2017/07/2017.html http://foodie-smashingpumkins.blogspot.hk[..]ns.blogspot.hk/2015/06/blog-post_13.html

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Mon Jul 03 01:03:21 HKT 2017 From /weblog/software_engineering

specification


Painless Functional Specifications - http://www.joelonsoftware.com/articles/fog0000000036.html

How to write a project specification - https://jaxenter.com/write-project-specification-135067.html

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Sun Jul 02 21:38:24 HKT 2017 From /gallery/Home/YimKan/htc

VIDEO0032



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Sun Jul 02 21:37:42 HKT 2017 From /gallery/Home/YimKan/htc

VIDEO0031



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Sun Jul 02 19:06:52 HKT 2017 From /gallery/Home/YimKan/htc

VIDEO0030



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Tue Jun 27 17:11:29 HKT 2017 From /weblog/career/jobs

interviewer tip


The best way I've found to interview candidate developers is to pair program with them to do real work on the actual code of the project that is hiring. If not possible, give programming exercise which is:

The exercise must involve working with current development tools.
The exercise must require the candidate to apply important features of the language.
The exercise must involve understanding and working with existing code.
The exercise must involve error handling.
The exercise must involve testing.
The exercise must offer scope for domain modelling.
The exercise must involve asking questions.
The exercise must be realistic.
The exercise must involve changing requirements.
The exercise must offer the candidate enough rope to hang themselves.
The exercise must test many different skills and practices.

A good interview programming exercise takes at least an hour. - http://nat.truemesh.com/archives/000630.html

The other interesting reading - http://blog.secosoft.net[..]ass-kickin-interviewscreening-questions/

Phone interview - http://www.joelonsoftware.com/articles/ThePhoneScreen.html

Questions that somebody like to ask... although I think this guy is a bit arrogance - http://softarc.blogspot.com[..]y-favorite-java-developer-interview.html

Another interview question and answer - http://journeymanjournal.blogspot.com/2005/03/sir-am-i-hired.html http://paultyma.blogspot.com[..]/howto-pass-silicon-valley-software.html http://www.codinghorror.com/blog/archives/001042.html

How about lie at CV? http://jroller.com[..]mon?entry=lying_on_your_r%C3%A9sum%C3%A9

Interviewing in google - http://pyre.third-bit.com/blog/archives/000174.html

What interviewee should asked at interview - http://blog.reindel.com[..]programmer-should-ask-on-a-job-interview

What should not waste time to ask the candidate - http://www.innerspace.com.hk/cl_life.html

http://www.ehow.com[..]303_use-technique-ace-job-interview.html

Beware of the small things during interview - http://cn.wsj.com/big5/20100115/eoe145304.asp

The concern of putting negotiable in salary - http://jobtipsforgeeks.com/2014/08/08/negotiable/

http://www.zdfs.com/code/2015/on-interviewing-software-engineers

how-to-carry-out-technical-recruitment - http://www.infoq.com[..]s/how-to-carry-out-technical-recruitment http://ramblinjan.com[..]ing-Process-is-your-engineering-process/

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Sat Jun 24 01:29:36 HKT 2017 From /weblog/health/food

cake


甜菜根冰皮月餅 - http://icook.tw/recipes/55680

parmesan-spinach-cake - http://www.webmd.com/food-recipes/parmesan-spinach-cake

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