In a report released today, the National Academies said that there are essentially three ways NASA can go about doing this, besides completely abandoning deep space forever: It can completely liberalize its health standards, it can establish more permissive "long duration and exploration health standards," or it can create a process by which certain missions are exempt from its safety standards. The team, led by Johns Hopkins University professor Jeffrey Kahn, concluded that only the third option is remotely acceptable."
But the datasets gathered in this way have been tiny — typically 20 people playing a handful of puzzles. Now one researcher has taken a different approach by mining the data from websites in which people can play games such as Sudoku. That's given him data on the way hundreds of players solve over 2000 puzzles, a vast increase over previous datasets and this has allowed him to plot the average time it takes to finish different puzzles. One way to assess the difficulty of Sudoku puzzle is in the complexity of each step required to solve it. But the new work suggests that another factor is important too — whether the steps are independent and so can be attempted in parallel or whether the steps are dependent and so must be tried in sequence, one after the other. A new model of this puzzle-solving process accurately reproduces the time it takes real humans to finish the problems and that makes it possible to accurately predict the difficulty of a puzzle in advance for the first time. It also opens the way for other studies of human problem solving using the vast datasets that have been collected over the web. Indeed work has already begun on the Sudoku-like puzzle game, Nurikabe."
The current services will be unavailable from 1 June 2014; user content will remain available for download until 31 July, at which time it will be deleted. For a spark of solace, the company promises to open source the backend code."
Entergy has reserved just over $600 million to date for decommissioning the Vermont nuclear plant, according to the Department of Public Service. This amount will not be adequate to meet the costs of full deconstruction, estimated at more than $1 billion according to the company's 2012 Decommissioning Cost Analysis report."