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Comment Re:Aluminium (Score 1) 365

Modern nuclear reactors can load-follow quite well, swinging output by 30% in fifteen minutes thanks to newer control tech and a lot of operational experience over the past 50 years. Load-following can even be done somewhat with older second-generation LWR plants. It's not actually done much since baseload nuclear power is very cheap in terms of fuel consumption and refuelling tends to be done at fixed intervals anyway. Other thermal generators like gas where the fuel is a major part of the cost of operations are normally used to top-up baseload stations -- in the UK the nuclear generators run full-out as much as possible with gas filling in much of the rest and coal as a cheap backstop, limited by pollution and carbon controls.

Comment Re:Aluminium (Score 1) 365

Most renewable generators get a guaranteed minimum payment for electricity they feed into the grid (in the UK where I live windfarm operators get about £145 per MWh) so the "excess" production is not free, it is paid for by the grid operators and ultimately the consumers even if it is not needed sometimes. If the renewable generators stored their excess production and dispatched it into the grid at times of low output that would be a different story, but that would cost them money so they don't do that. The round-trip efficiency losses are even more reason for them not to build storage into their operations.

Comment Re:Aluminium (Score 3, Informative) 365

Storage costs money. Lots of storage costs lots of money. Storage wastes energy too -- pumped hydro, the cheapest form of bulk energy storage has an input-to-output efficiency of about 65 percent. Baseload coal, gas and nuclear generation doesn't need storage to be useful and meet demand 24/7/365 unlike intermittent renewable generating capacity, but no-one ever adds the cost of storage to the cost of renewables when comparing prices.

Comment Re:Serously? (Score 1) 398

You mean like the major Japanese Army command centre in Hiroshima? Or the extensive Naval dockyards and repair facilities in Nagasaki, close to where the Allied invasion was going to hit the beaches in Kyushu? Nagasaki was actually a secondary target due to bad weather over the primary target, a place called Kokura Arsenal which might give you an idea why it was on the target list.

In reality the atomic bombs were used because they were ready to be used, just one more wonder weapon in a war filled with wonder weapons. They contributed to the decision by the Japanese War Party, the military/political group in power at the time, to surrender but it was mostly down to the Russians declaring war on Japan on the 9th of August 1945 and promptly destroying the last major Japanese army outside Japan itself, the million plus Manchurian occupation force with embarrassing ease.

Comment Re:Early days of KIA repeated (Score 1) 431

Diesel engines typically run at twice the compression ratio of a gasoline/petrol engine. They also last a lot longer than petrol engines in my experience. This may be because they are designed to deal with the higher compression and greater loads on crankshaft bearings etc. from day one. They do tend to be heavier than gasoline engines of the same power and torque though.

Submission + - Ask Slashdot: What's the best rapid development language to learn today? 2

An anonymous reader writes: Many years ago, I was a coder—but I went through my computer science major when they were being taught in Lisp and C. These days I work in other areas, but often need to code up quick data processing solutions or interstitial applications. Doing this in C now feels archaic and overly difficult and text-based. Most of the time I now end up doing things in either Unix shell scripting (bash and grep/sed/awk/bc/etc.) or PHP. But these are showing significant age as well.

I'm no longer the young hotshot that I once was—I don't think that I could pick up an entire language in a couple of hours with just a cursory reference work—yet I see lots of languages out there now that are much more popular and claim to offer various and sundry benefits.

I'm not looking to start a new career as a programmer—I already have a career—but I'd like to update my applied coding skills to take advantage of the best that software development now has to offer.

Ideally, I'd like to learn a language that has web relevance, mobile relevance, GUI desktop applications relevance, and also that can be integrated into command-line workflows for data processing—a language that is interpreted rather than compiled, or at least that enables rapid, quick-and-dirty development, since I'm not developing codebases for clients or for the general software marketplace, but rather as one-off tools to solve a wide variety of problems, from processing large CSV dumps from databases in various ways to creating mobile applications to support field workers in one-off projects (i.e. not long-term applications that will be used for operations indefinitely, but quick solutions to a particular one-time field data collection need).

I'm tired of doing these things in bash or as web apps using PHP and responsive CSS, because I know they can be done better using more current best-of-breed technologies. Unfortunately, I'm also severely strapped for time—I'm not officially a coder or anything near it; I just need to code to get my real stuff done and can't afford to spend much time researching/studying multiple alternatives. I need the time that I invest in this learning to count.

Others have recommended Python, Lua, Javascript+Node, and Ruby, but I thought I'd ask the Slashdot crowd: If you had to recommend just one language for rapid tool development (not for the development of software products as such—a language/platform to produce means, not ends) with the best balance of convenience, performance, and platform coverage (Windows, Mac, Unix, Web, Mobile, etc.) what would you recommend, and why?

Comment Re:I wonder (Score 4, Interesting) 190

A couple of Tu-95 Bears flew down towards the north of Scotland a few weeks back, the RAF went up to welcome them outside the national limit and got some nice pictures. I grabbed them off the MoD website and bundled them up since most of my friends are Apple fans and don't do Flash.

https://www.mediafire.com/?fs5...

Runs to about 12MB or so as a zip download.

Comment Re:Godzilla! (Score 2) 75

Actually the Japanese are burning more LNG with some extra coal to replace some of their nuclear generating capacity. In the 12 months up to March 2013 TEPCO burned 23 million tonnes of LNG and 7 million tonnes of coal to generate electricity, in comparison in the same period ending March 2011, just after the earthquake and tsunami they burned 19.5 million tonnes of LNG and 3.5 million tonnes of coal. LNG has twice the energy of coal tonne for tonne.

http://www.tepco.co.jp/en/news...

As for coal as a long-term solution the Germans plan to be still generating at least 40% of their electricity from coal and lignite by 2050. That seems quite long-term to me. I doubt very much the US will have stopped mining coal in South Dakota and West Virginia to burn in power stations by then either. The Japanese don't have any significant amounts of native coal left to burn, no oil and no gas so they have to import it. Uranium is cheap, their nuclear generating plants are still in place ready to restart and their balance of payments are in the crapper for the 22nd month in a row mostly due to buying carbon instead.

Comment Re:Keystone XL (Score 1) 411

Which refineries in the north? The Texas and Gulf refineries have underutilised capacity especially for the heavy form of oil that is the end product of the Athabasca tarsands production. That's why the producers want to pipe it across America north to south, it's cheaper than building new refineries in Canada and it guarantees jobs and profits for US-based operations.

As for shipping the refinery product to Europe or China, if the US consumers are willing to pay the going price for the refinery output then it will sell in America. If other folks abroad are willing to pay more even with the shipping costs well that's capitalism for you, you know, free movement of goods and materials, one of the lynchpins of an unregulated market.

Of course you do realise that the Athabasca reserves are not American property but in fact the product of a foreign country being imported to the US, that free market capitalism at work? Why should the end result of processing foreign oil be reserved to subsidise US consumers when the source material is imported?

Comment Re:obsolete (Score 1) 323

you're lying, or maybe you're just ignorant or you got your "information" from bullshit anti-nuclear blogs and such, but...

a) nuclear power reactors are decommissioned to "greenfield" status, that is the land is fit to grow crops on afterwards. It's a lot more work than brownfield where the ground will be repurposed for industry but it's a cost the nuclear industry has to bear unlike, say, coal mining.

No a nuclear site doesn't need to be quarantined for "hundreds of years". Heck, even after Chernobyl burned its core to the atmosphere the other three reactors on the site were kept in operation. No quarantine.

Storm surges affect ex-nuclear sites in the same way they affect farmland since they present the same levels of threats of toxicity. If you're really worried about flooding then look to coal mines and coal power stations which regularly dump millions of tonnes of poisonous effluent into streams and drinking water after flooding takes out their inadequate levees and dykes. Nobody cares much though because it's not scary radioactivity.

As for the British SafeStor decommissioning system, it's an alternative method to prompt disassembly of a power reactor -- tear down everything around the containment since it's not radioactive and then wait about 60 to 80 years for the remaining radioactivity in the pressure vessel and surrounding structures to decay to the point where it can be dismantled with minimal precautions. Other countries deal with this differently, in the US the reactor vessel is usually extracted promptly and put in a pit to "cool down" for about the same length of time so the entire site can be cleared more quickly.

Comment Re:Yeah... (Score 1) 146

They're not using any pesticides or herbicides as they would have to in the "wild". There are no caterpillars, no fungus or microbial antagonists or weed seeds that could destroy or deplete the crop, they're kept at bay because the facility is a clean-room setup with filtered air and water. That's the big "no chemicals" deal with this greenhouse.

Comment Re:You real what you sow (Score 2) 283

Plenty of countries don't offer automatic citizenship to people who marry one of their citizens. The US doesn't, for example. They don't offer green cards or right of residence automatically either. Friends of mine who got married in the UK tried to move to the US where the wife was a natural-born citizen but her British husband was refused leave to stay. They lived in the UK for several years and finally after many appeals her husband managed to get a green card and they moved to the US. As far as I know he still hasn't got citizenship, I don't know if he's applied for it.

I know a few non-Japanese who are long-stay residents of Tokyo and environs. One is married to a Japanese woman and another has been engaged to a Japanese woman in the past but as far as I know neither wants citizenship.

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