"The purpose of this site is to provide a comprehensive list of links related to optics and optical simulation in general. Topics include optical design, optical engineering, illumination, Laser, optical materials, thin film coatings, and many more subjects needed to build and analyze complex optical systems."

"I personally scan the books I bought because I’m tired of thousands of them cluttering up my house, ending up lost at the bottom of a box marked Dishes, getting eaten by bugs, or attacked by acid inherent in the paper. If you don’t like the idea of reading electronic editions of books, stop reading here! Also, if you think format-shifting is intellectual property theft, stop reading here. There are as many reasons people have for scanning books as there are people:…"

"These are basic life skills that everyone should want to master. If we taught them broadly, and if everyone learned them, then this sort of mastery wouldn’t attract the geek label. But we don’t teach these skills broadly, most people don’t learn them, and the language we use isn’t our friend. If systems thinking is geeky then only geeks will be systems thinkers. We can’t afford for that to be true. We need everyone to be a systems thinker."

"How do we choose k, the number of clusters ?
This topic is so annoying, that I'm going to devote more than one post to it. While choosing k has been the excuse for some of the most violent hacks in clustering, there are at least a few principled directions, and there's a lot of room for further development."

"This seems a reversal of some things I have said in the past about the need for change control. I said that "shit happens" is not an excuse any more. I still believe that. Just because some incidents will remain unpreventable doesn't mean that many others can't be prevented. Just because fixing a problem in one place means higher risks will be taken elsewhere doesn't mean we shouldn't fix the problems. And just because complex systems are impossible to stop breaking doesn't mean that there isn't negligence behind some breakages."

"There's plenty to argue about here and he presents in black and white some issues that are full of grays, but chances are you won't spend 20 minutes today with a smarter person. It's worth watching and thinking about …"

"What really makes the current period stand out is the number of people (and percent) that have been unemployed for 27 weeks or more. In the early '80s, the 27 weeks or more unemployed peaked at 2.9 million or 2.6% of the civilian labor force.

In January, there were 6.3 million people unemployed for 27 weeks or more, or 4.1% of the labor force. The number declined slightly in February, but this is much higher than earlier periods."

"Wow. If a person markets something, like a book they've written, or a product they are selling, it is regulated as if it were advertising published by a media company, such as a newspaper, TV, magazine, etc.

That means everyone is now a media company. And subject to the same regulations – at least in the UK. Wow."