Author Archives: Allen

Blog has been migrated!

The original blog has been migrated to WordPress! 新站開張!我原本的Blog已經搬到這邊啦!

Posted in 未分類 | Leave a comment

Logistics regression in Chinese

Here are recommended posts in Chinese for understanding logistics regressions. The readers can read them step by step.  1. 機器/統計學習: 羅吉斯回歸(Logistic regression), URL: https://chih-sheng-huang821.medium.com/%E6%A9%9F%E5%99%A8-%E7%B5%B1%E8%A8%88%E5%AD%B8%E7%BF%92-%E7%BE%85%E5%90%89%E6%96%AF%E5%9B%9E%E6%AD%B8-logistic-regression-aff7a830fb5d 2. 你可能不知道的邏輯回歸(Logistics Regression), URL: https://taweihuang.hpd.io/2017/12/22/logreg101/

Posted in Data Mining, Machine Learning | Leave a comment

科技的進步,學無止境

在2006年左右,我還在唸嘉義大學數學系時,跟同學分工合作,用PHP 5+Dreamweaver 寫學校處室網站,那時候學校IT不給MySQL/Sql Server,我自己還默默用很簡單的檔案系統處理函數,定義好資料結構,一行一行把「最新消息」等訊息,存在單一檔案作為offline database使用(那時候學藝不精,不知道有Sqlite可以用)。就這樣把學校處室的消息發布功能做了出來,還具備CRUD功能。  在那個大學年代,身兼學校的BBS系統站長,在那邊辛苦學習FreeBSD , Linux⋯當起MIS,三不五時就是去修伺服器,怎麼用fsck修硬碟, Make tools, build kernel 還自己去學怎麼剪RJ 45網路線,讓Server可以正常運作(可見那時候多窮,還要自己剪網路線)。 就這樣懵懵懂懂地大學畢業。 碩士班時期,實驗室還沒有積累一些關於data mining智慧資產,自己寫了一些演算法,像是PrefixSpan sequential pattern mining. 為了求效能,還全部用C++搭配STL寫。自己排crontab job,搭配bash script來產生自己要的實驗記錄。 博士班時期,老實說蠻精彩的。 當了三年的兼任助理,幫忙編hadoop教材…。為了自己的生計,還幫學校處室架設Wordpress,改別人的theme,甚至去看wordpress template怎麼寫,修掉別人模板的bug。也稍微懂得怎麼調整Apache的參數讓系統效能能夠跟得上來。 因為過去都用PHP寫網站,也順便接了幾個案子,像是做一些報名系統,多語系網站建置。 去當了幾家公司的兼任工程師,都是以C# + ASP.Net/MVC 作為主要工作技能。 曾經接了某個專利事務所的案子,幫別人寫Chrome外掛(後續做得不錯,顧客還有回鍋要我再幫忙開發,但是要顧學業,就婉拒了。) 曾幫博弈平台公司維護模組(這期間眼睛也去動手術了)。 為了打軟體競賽,還去用MongoDB,寫寫jQuery and Bootstrap。 為了做某公司的軟體專案,自己去玩Zebra ZPL印表機語言, WCF跟實作軟體序號與數位簽章演算法。 為了幫德國實驗室的同事做Big … Continue reading

Posted in 未分類 | 2 Comments

Raspberry Pi Camera + OpenCV

If you are interested in how to use Raspberry Pi Camera + OpenCV to capture images, here is a great post in Chinese.  https://link.medium.com/k2aEqonas8 However, the post had something wrong. If you want to install OpenCV packages of Python 3, … Continue reading

Posted in Python, Raspberry Pi | Leave a comment

FFMPEG: Decode and then encode frames to JPEG images

I’ve used FFMPEG library for a while. Actually, the FFMPEG library’s decoding process flow can be described as the following picture. If you want to read the videos and then save to jpeg file, you can take a look on … Continue reading

Posted in C, FFMPEG | Leave a comment

The introduction for JavaScript ES6’s classes

Do not understand the class features of JavaScript ES6? You can take a look on this introduction in Chinese.  https://shubo.io/javascript-class/

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Speed up ActiveMQ performance by 25x

Sometimes we encounter the performance issue for persistent messaging using ActiveMQ.  Here’s the best practice on Linux system to accelerate it.  https://blog.christianposta.com/activemq/speeding-up-activemq-persistent-messaging-performance-by-25x/

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使用 git worktree 建立多個工作區

Reference:  https://medium.com/@kmsh3ng/%E4%BD%BF%E7%94%A8-git-worktree-%E5%BB%BA%E7%AB%8B%E5%A4%9A%E5%80%8B%E5%B7%A5%E4%BD%9C%E5%8D%80-5a02f6d9d3fd

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Materials for Neural Network

Some materials are enclosed here.1. 深度學習(二): 反向傳播 URL:http://chansh518.github.io/deep%20learning/2016/08/08/Deep-Learning-Notes-Backpropagation.html2. 一文看懂常用的梯度下降算法 URL: https://blog.csdn.net/u013709270/article/details/786675313. 邏輯回歸代價函數及其梯度下降公式 URL: https://blog.csdn.net/Mr_HHH/article/details/789347934. The Back Propagation Algorithm. URL: https://page.mi.fu-berlin.de/rojas/neural/chapter/K7.pdf5. Derivation of Back Propagation Algorithm for Forward Neural Networks. URL:  http://www.cs.put.poznan.pl/pliskowski/pub/teaching/eio/lab1/eio-supplementary.pdf6. 凸優化 梯度下降。URL: http://www.hanlongfei.com/凸优化/2015/09/29/cmu-10725-gradient/7. Geadient Descent demystified. URL:  https://towardsdatascience.com/gradient-descent-demystified-bc30b26e432a8. An introduction to gradient descent … Continue reading

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It’s time to push my career forward

After a long time, almost 3 months, I’ve done my PhD degree. In the past, I could not image that I get my PhD. Thanks for my supervisor’s and family’s great supports. I did it!Through the training of PhD, making … Continue reading

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