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  App's user value doesn't necessarily bring business value

There is an old saying in Internet world, you can get business value as long as you can achieve user value. Is this statement outdated in mobile Internet era? This statement originated from PC Internet era, but now the time users spend on PC drops and user behavior tends to be stable and conservative. In contrast, people are more willing to stay on mobile devices. The difference between PC and mobile is that users are freely to move around on PC end. People can navigate from one link to another ...

   App,Business value,User value     2013-06-25 10:52:12

  Goodbye Manual Processes, Hello Automation Certificate Lifecycle Management Like It’s Supposed to Be

At the heart of every story lies a villain and a hero. In the never-ending story of certificate lifecycle management, there’s no bigger villain than manual effort. Destructive, irrepressible, and risk-laden, this villain causes nothing but mayhem and loss. Automation, the hero, is the complete opposite of manual effort. Proactive, solution-oriented, and breach-proof, this hero deserves recognition, allegiance, and attention, yet they get none of that from a majority of today’s organi...

   DATA SECURITY,CERTIFICATE     2023-06-20 08:10:02

  Some thoughts about competitive programming

Many programmers may have experience in participating different kinds of coding competition while they are in college. Many of them are hired by top IT companies for their excellent performance during these kinds of coding competitions. There are some famous competitions organized by IT companies such as Google Code Jam, Facebook hackathons etc. Coding competitions are places where programmers can show their talents in programming and the skills they have. Usually programmers will solve some to...

   Coding,competition     2014-03-02 07:26:21

  Using htpasswd to protect your website in Nginx

We need to build a password protected website frequently such as an internal website within the team, demo website. Here what we are talking about is password protection in Nginx server level instead of application level registration and login. We are going to use Nginx server configuration and htpasswd file to achieve password authentication. The final result looks like below(Different browsers may have different interfaces): If the authentication fails, it will report a HTTP error: 401 Author...

   Nginx,Password protected,htpasswd     2013-06-07 21:35:27

  Why does LinkedIn migrate to NodeJS from Ruby?

Node.js, the server-side JavaScript-based software platform used to build scalable network applications, has been all the rage among many developers for the past couple of years. Node.js uses an event-driven, non-blocking I/O model that makes it lightweight and efficient, perfect for data-intensive real-time applications that run across distributed devices. Because of these advantages, there are many websites are migrating to Node.js.One of them is LinkedIn. LinkedIn was initially built on Ruby...

   LinkedIn,NodeJS,Ruby     2014-03-21 23:39:25

  Build route graph of Hurricane Sandy

Hurricane Sandy swept US east side and landed in New York, it killed 113 persons and incurred 50 billion US dollars economic loss. Sandy is also considered as the most expensive hurricane. We will now use matplotlib and basemap libraries in Python to build a route graph of Sandy. Below is the animated GIF. Shadow is added in the graph to show the time at night, we can see from the graph that Sandy stayed a while in Panama after emerging, then it went through Cuba and became Hurricane-2. Late...

   Hurricane Sandy,Route graph,Python     2012-11-17 07:58:13

  Data as code

What is a good command line parser API? A good command line parser should consider below 5 aspects: Support convenient help information generation Support sub commands, for example, git has push,pull,commit sub commands. Support single character option, word option, flag option and option with parameter. Support default option, for example, if no -port is set, set it as 5037 Support usage model, for example, tar's -c and -x is mutually exclusive, they belong to different usage models. Here are...

   Command line,API     2013-08-08 22:40:36

  Using public key authentication in SSH

SSH is a popular cryptographic network protocol for secure network service operation. It is frequently used in remote server login. For a system administrator or software developer, SSH is frequently used to access remote servers or development servers or testing servers etc.  To login with SSH, there are different authentication mechanisms : password, public key and interactive etc. If a remote server needs to be accessed frequently, password authentication may be too troublesome as p...

   LINUX,DEBUG,SSH,PUBLIC KEY     2016-09-10 05:55:46

  It makes nothing but sense...Mobile Payment...

Chinese New Year is around the corner, every place in China and lots of places in the work have been in the CNY mode. People are rushing out to get all the stuff ready to welcome the New Year Eveand the Spring Festival. I also packed my stuff and flew back to my howntown in China to enjoy the great moment to stay with families and hang out with friends whom I have't been seeing for almost one year. I am exited... However, the first thing stunned me is not my friends but the mobile payment s...

   CHINA,WECHAT PAY,ALIPAY,MOBILE PAYMENT     2018-02-12 00:07:46

  Select top 3 values from each group in a table with SQL

Yesterday, my friend Liu Bing asked me a question about how to select top 3 values for each person in a database table using SQL. I think this question is interesting and it deserves some thoughts. Here I record down how to solve this issue. Assume we have a table which has two columns, one column contains the names of some people and the other column contains some values related to each person. One person can have more than one value. Each value has a numeric type. The question is we want to se...

   SQL,Correlated query,top 3     2013-05-23 03:21:25

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