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Comment: Icebergs? (Score 2) 330

by rover42 (#48614453) Attached to: 11 Trillion Gallons of Water Needed To End California Drought
When I lived in Saudi Arabia (early 1980s) there was talk of towing a few icebergs from the Antarctic into the Red Sea where they would melt and produce fresh water. At least one study claimed this was feasible, given a few large nuclear-powered tugs.

The US has a number of nuclear-powered naval vessels and a large supply of ice in Alaska. Canada or Russia might provide more. Would something like this work for California?

Comment: Use on Venus? (Score 1) 145

by rover42 (#48476801) Attached to: Scientists Develop "Paint" To Help Cool the Planet
In some ways Venus is a much more attractive target for off-Earth human expansion than any of the other possibilities. Notably, it is closer to the Sun so anything solar-powered would work about twice as well. In other ways it is very unattractive indeed. One of those is surface temperature, several hundred degrees too high for most Earth life forms.
Could this stuff, or something related, help us reduce temperatures on Venus? http://en.wikipedia.org/wiki/Terraforming_of_Venus/

Comment: Not tust Japan (Score 1) 419

by rover42 (#48394067) Attached to: Japanese Maglev Train Hits 500kph
China, Korea and many European countries already have large high-speed rail systems and are building more. China's fastest is 400+ km/h from an airport to central Shanghai, but they have lot of 350 km/h trains on longer routes. Compared to other highly industrialised countries, US passenger rail is downright primitive & Canada is even worse. An article on the Chinese system: https://en.wikivoyage.org/wiki...

Comment: Can you do a conference paper? (Score 1) 182

by rover42 (#47965309) Attached to: Ask Slashdot: Who Should Pay Costs To Attend Conferences?
It is almost certainly too late for this conference, but for future ones it may help if you can do a paper or presenation. First off, many conferences let presenters in free or at least give them a discount. Second, it may help make the case to your employer, especially if the paper publicizes a project there. If nothing else, such papers look good on your resume.

Comment: Text-scanning programs (Score 1) 172

by rover42 (#46936047) Attached to: Ask Slashdot: Beginner To Intermediate Programming Projects?
You want to use Python, which is a good language for text manipulation. That suggests various projects based on scanning through text. Take any interesting large piece of open source software. How many switch() statements lack a default: case for error handling? You can get a first approximation with a few lines of shell & grep, but doing it right would need a language like Python and a moderate amount of work. What else would be easy to check? Take text samples from several different news sources. How do their vocabulary choices differ? Does that indicate their political biases? Can you program some of the standard indicators of reading level (see Wikipedia)? Do they get different scores?

Comment: Try some classic problems? (Score 1) 172

by rover42 (#46936005) Attached to: Ask Slashdot: Beginner To Intermediate Programming Projects?
There are a number of problems that are often used as exercises. Textbooks at any level from high school to grad school have examples; here are a few off the top of my head: Games: start with something really easy like tic-tac-toe, then try more interesting games. 8 queens: put 8 queens on a chessboard so that none of them checks any other. The easy version is to just find one solution. It gets a lot harder if you want to do it efficiently and/or find all possible solutions. Doing it in reasonable time for N queens on an N by N board is really hard. Markov chains: Analyze some large sample of text to count how often combinations of words or letters turn up. Then write a program to generate text using those statistics. How long a chain do you need to look at to get more-or-less sensible output?

Comment: Instrument the code (Score 2) 308

by rover42 (#46141017) Attached to: Ask Slashdot: What Do You Do If You're Given a Broken Project?
As others have suggested, talk to the original developer, document the problems and keep your boss informed. If you are a contractor being supplied by one firm to another, keep the appropriate people at both companies informed. Also, look for ways to measure the problems. First, can you run the code through lint(1) or crank the compiler options up to reveal problems? Then can you add runtime error checking or data validation code? This may help you fix things and/or be useful as documentation. Once, when working as a tech writer, I wrote a half a dozen little scripts to inspect 600,000 lines of C from a dozen programmers. Hmmm. Less than 5% of switch() statements had a default: case for error-checking. Less than 20 uses of the assert() macro in the whole code base. And so on. The programmers mostly came from a Pascal-like environment so almost none were using C idioms like if( (p = fopen(...)) == NULL) for error checking. That is OK but I found dozens of cases where they were allocating memory, starting processes or opening files, sockets or pipes with no error checking at all.

Comment: Religion & epidemics (Score 1) 70

There was a medieval cholera epidemic spread by multiple groups of religious pilgrims. It began with Hindu pilgrims bathing in the sacred Ganges at Varanasi & then going home; that spread it over most of northern India. Moslem pilgrims going West for the Hajj then spread it to Persia, Baghdad, Jerusalem, ... Finally, crusaders brought it to Europe. It killed tens or hundreds of thousands in all those places.

Comment: Rubber plants? (Score 1) 242

by rover42 (#44543861) Attached to: Looking Beyond Corn and Sugarcane For Cost-Effective Biofuels
In the 80s, I met a PhD biochemist who had worked on making synthetic rubber from petroleum products. He said going the other way -- from the latex in rubber tree sap to something that could substitute for gasoline -- looked feasible. All the science was known and in principle the process would be straightforward, but neither the engineering nor the economic/political problems involved had been solved. Is anyone looking at this sort of thing today? What about oil-producing plants, such as oil palms?

Memory fault -- brain fried

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