BitCoin
What is BitCoin Mining?
The block chain is a race of horses
Guess a value for the empty nonce in the last block that results in a hash with sufficient number of leading zeros and you win 18000 dollars.
Why a block chain database?
- A regular online bank account keeps you from spending digital money more than once. That is possible because it is a centralized design that subtracts the amount spent from your account. You can not change this because you do not have the ability to change the database.
- What do you do if there is no central database because you do not want to rely upon a central authority? How can the balances in everyone's accounts be maintained in a trustworthy fashion? How do you keep a person from spending the same buck in his bank account 2 times when it is only an entry in a database that they have access to? Access to a normal database would mean you could set any value you wanted. The skies the limit!
- Remember the database needs to be hard to fake up but easy to read. Everyone needs be able to read it. Everyone needs to be able to tell which version of it is valid. Have you ever downloaded a file that had a hash value to compare with the hash value that you compute on the version you download to verify it is not corrupted? This same methodology is used with the blocks in the database chain. The hash appended to the end of the block has to have a special value and finding that special value requires lots of computation. This makes it easy to read and verify the database block but hard to make the block in the first place.
Computing
How to Download Subtitles as Text From Youtube
This is a summary of how to download and include a transcript of a youtube video. It is mostly obsolete except for the toggle transcript.
Procedure using Google Chrome
- Open up the developer tools
- Go to console
- Paste in: if(yt.config_.TTS_URL.length) window.location.href=yt.config_.TTS_URL+"&kind=asr&fmt=srv1&lang=en" or alternatively go to this file on google docs
- The XML caption subtitles will come up as transcribed by google will come up. You can copy and paste this directly into a SOURCE pane in your wordpress editor.
- Highlight your subtitle text and make sure it is all set to the same color if you want something that looks like a paragraph and is pleasing to the eye.
- If you want to strip out the XML tags first by using an online tool. I have not found a satisfactory one yet.
Research LInks
- DownSub.com: Download Subtitle – method above is hit and miss. Looking for a new method.
To add this transcript into a blog post afterwards I use the WordPress Show Hide plugin syntax:
Put the toggled text in between the following tags:
showhide type="post" more_text="Show Transcript…" less_text="Hide Transcript…"] [/showhide]
Add a square bracket in front of the phrase. This blog already has showhide installed so I could not use a complete tag set or the text would not display.
Computing
Toggling WordPress Post Text Visibility with the Show Hide PlugIn
How to Show and Hide Text in WordPress Posts with the Toggle Effect Summary – follow the sequence To see an example of what this does go here and click on "Show Transcript" below the video. A transcript of the video Read more…
Computing
DIGIPASS GO3
How does Digipass work?
The secure key has a unique serial number allocated to it which is only known by the bank. The key has a clock in it which is synchronized with the clock on the bank's computers before it is sent out. You set the PIN on the secure key which is only known by you.
I guess the internal clock must only be accurate to human scale time intervals.
Research Links
