Sorry for being no update a long time. Since my sites including here were hacked last year and I have been busy in switching host recently. If you are a frequent visitor to this site, you may know I have updated some pages but the more important is that more updates are coming soon. So, I reinstall the update blog and let you know the updates clearly. Besides, I re-activate the commenting system, hope the anti-spam can do its job. Then I can have more interactions with you. And you can subscribe for the update feed by saving the rss…