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Comment Re:Distances (Score 1) 105

If I were picking a number out of thin air I'd certainly go higher. The question is how he arrived at that number, and I suspect economies of scale have something to do with it. Scale can do funny things to your calculations. Things can get harder, then easier, then harder again as you go up.

I once had a colleague whose first engineering job out of college was to do a reverse engineering specification on a prototype submersible; the Navy was pleased with the low cost of the prototype and thought it might like a second one. The problem was that the prototype was made by scrounging surplus bits and pieces; building a second one that was exactly the same would have cost 10x as much because you'd have to hunt down an exact replacement for each part. But if you were building a 100 units, you probably could do it for 100x the cost, because you could amortize the project's fixed costs over more units: source the odd parts, reverse engineering them if necessary, or doing design revisions with an eye to making it reproducible.

Comment Re:That's great.. (Score 1) 70

Luckily, we have a fair number of historical examples drawn from the lower-tech world of competition for the water of a given river between multiple parties that live along it.

Atmospheric moisture flows require more sophistication to track and exploit; but conflict patters should be pretty similar. Good thing land wars in Asia never go poorly!

Comment Re:Never worked before, will never work now (Score 1) 70

I too find it hard to believe that there is any empirical justification for trying this. That said, I'd like to know what they think indicates this will work. I'm wondering whether they might be dealing with some kind of post hoc ergo propter hoc scenario where cloud seeding efforts coincided with changing rainfall patterns.

In any case, the place they're trying this appears to be Qinhai Province, up on the Tibetan Plateau. The population density there 7.8/km^2 -- roughly similar to Wyoming (5.97/km^2).

Comment Re:The questioner reveals their own dishonesty (Score 1) 299

Under Obama, we stopped counting people as unemployed if they gave up looking for a job. Such people are difficult to track is the argument.

Actually unemployment has always been calculated that way. It's the way economists do the calculation, not some kind of nefarious political innovation.

As for tracking the people who give up looking, the labor department does track them. How else do you know that the participation rate is low? The thing is that while unemployment (as it has always been reckoned) has recovered to pre-Great Recessions levels, participation rates remain unusually low, and that's just something you have to take into account when you're comparing unemployment rates in 2008 to 2016: the denominator has a distinctly different character.

What really gets interesting is if you look at who is not participating. The lions' share of non-participants are Boomers nearing retirement. This isn't a happy statistic, however. I think it reflect the synergistic effects of age discrimination and long-term unemployment. We also have high rates of underemployment as well -- people who are highly skilled working low-skill jobs for example.

The overall picture is mixed, fair-to-good-ish for many but extremely grim for sizable numbers of people.

Comment Re:Who Has EVER Trusted Government Data? (Score 2) 299

Who trust government data? Anybody who uses a USGS map. Or a weather forecast that uses satellite data. Or who uses a GPS (both the satellite signal and the base map, which is compiled by private companies from government sources).

Now any statistic is capable of misleading, if you choose to misinterpret it. Take unemployment. I think that figure is accurate, it just doesn't mean what people think it does. By 2016 unemployment had recovered to where it was before the Great Recession, but if you think that means the government is fraudulently telling you that the job picture is good, that's you misinterpreting what it means. The low unemployment rate masks (a) relatively low labor participation and (b) disastrously low job growth and labor participation in certain regions of the country -- particularly rural and small to middle-sized cities. How do I know this? Well, government data, obviously.

You are conflating "data", with "information" and "opinion". The Food Pyramid is opinion, not data. If you think for yourself and drill down into the facts a bit, you'll find that government data is pretty useful. Opinions, less so.

Comment Re:You just now started worrying? (Score 1) 299

If you think that the Republicans are the party of fiscal responsibility I suggest you go back and look at the changes in Federal deficits by fiscal year when they are in charge. Note that if a president takes office in FY X, FY X+1 is the first budget he submits and FY X+2 is the first budget that fully reflects his priorities.

Comment Re:Distances (Score 1) 105

Japan's maglev system is proven technology, already at the low end of the Hyperloop speed range and projected to reach over 900km/h in time. Hyperloop is expected to hit around 1200km/h, so I just can't see the benefit being great enough to outweigh the disadvantages.

The reason to choose Hyperloop over Maglev isn't speed, it's projected cost. Musk thinks he can build the things for $11 million/km. That's about a quarter of what maglev would cost -- assuming that Hyperloop even works.

There isn't a lot to choose between 30 minutes LA to San Francisco and 45 minutes. Over longer haul routes the technology is supposed to eventually go much, much faster than maglev, but the key in the near future will be to beat maglev on cost over medium distances. And to actually work.

As for comfort, Hyperloop proposes to turn intercity travel into something more like a cross city subway ride. In fact (assuming it works) you'll be able to get from New York to Washington DC in less time than it takes to cross Brooklyn on the MTA.

Comment Re:Contrast this with the incoming administration (Score 1) 280

Solar is getting no where near to the price of coal. We're still paying 0.528kWh for solar here in Ontario, the price we were paying for coal when the last plant shut down was 0.043kWh.

Of course when you're shutting down coal power plants the price of coal is going to drop. Canadian coal demand dropped by 45% in the ten years prior to Thunder Bay shutting down, you have to look at those prices in the context of a collapsing domestic market. Coal prices would have been much higher with stable or growing domestic demand.

Latitude and climate also affect the cost of solar, and last time I checked most of the population of the US (which is the country we're talking about here) is south of Ontario. Solar is much, much cheaper in Florida for example. But even where I live in Massachusetts (same latitude as SW Ontario) you can get rooftop solar panels for US $2.50 / watt (6.25 Canadian) if you pay for them yourself and your house is favorably situated. That means to beat the Can $0.043/kwh benchmark, solar panels here in Boston have to run for about ten years. Solar panels have an expected service life of thirty years.

Of course when you get into realistic economics things get complicated. But a lot of my engineer friends have chosen to pull the trigger on rooftop solar, and they aren't afraid of doing ROI calculations. It's not for everyone yet, nor is it a solution for everything. But it's economical for some people in just about every part of the continental US, and that's a significant development.

Comment Re:Another SLOW Language (Score 1) 290

The JIT and the GC are the two parts of the VM that must be able to escape the constraints of the language model (the JIT must be able to generate executable code, which the Java security model doesn't permit, and the GC must be able to allocate memory and assign it a type and delete objects that are still reachable). Absolutely everything else in a JVM can be implemented in Java fully respecting the language model. You can write almost all of a JVM in Java, as long as you have a small amount of statically compiled Java code that is treated as trusted and so permitted to violate the language invariants. This is precisely how Smalltalk VMs are typically written. There is no requirement for C/C++ to implement Java, it's just an easy way of doing it.

Comment Re: Don't look at it that way... (Score 1) 153

If you're creating a database table, 64 bits doubles the size of the index column. If you're creating a database table in normal form, then you'll have a number of tables that are simply pairs of two indexes, so you will double the size of entire tables. That's going to have big cache and memory overheads and is definitely not a simple 'let's always do that' choice.

Comment Re:More features. (Score 1) 290

I honestly couldn't say. I learned C++ about 20 years ago, hated it, tolerated it a bit while working on LLVM, revisited it in C++11 and discovered that the language had changed beyond all recognition and didn't suck anymore. I like cppreference as a reference for the standard library, but I've not used a tutorial (and I definitely wouldn't recommend the old book that I read).

Comment Re:how about modules? (Score 1) 290

Yes, modules as proposed for C++ (which don't give you what the grandparent wanted: a clean separation between interface and implementation) are pretty easy. Clang has mature support for them and even some logic to implicitly generate modules from headers. They give you a compilation speedup, which is sorely needed for C++, but not the benefit that the grandparent was looking for, though they do at least require that you don't litter your headers with #ifdefs (which means C++ and C can't share modules).

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