Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!


Forgot your password?

Comment Re:sunfire / in my stellerator / makes me... happy (Score 1) 93

So on average the fission reactor material only has about 10% of its atoms displaced over the lifetime, while the fusion reactor would have, on average, every atom displaced hundreds of times over the lifetime.

How can you make generalized statements like that? Cross sections vary by many orders of magnitude Fission reactors are generally made of steel, which is hardly setting any records in terms of low cross sections. The smaller the reactor, the less material you have to replace, and the more expensive the material you can use. And being "displaced" is not a fundamental universal material property effect, it depends on how the material responds to radiation damage, which varies greatly. Generally materials respond better at high temperatures (annealing), and fusion reactors operate of course at far higher temperatures than fission reactors.

I have trouble seeing how one would consider neutrons per square meter to matter more than neutrons per MeV. Because neutrons determine what you're going to have to replace, and energy determines how much money you get from selling the power to pay for said maintenance. You can spread it over a broad area and do infrequent replacements, or have it confined to a tight area and do frequent replacements, the same amount of material is effected. Some degree of downtime for maintenance is normal in power plants - even "high availablility" fission plans still only get ~85% uptime.

Comment precalculating inner loop is faster & more eff (Score 1) 261

You bring up two important points. First, you said "we" want power efficiency. The article says Intel is going to provide efficient CPUs. It does not say that everyone will always prioritize efficiency over speed for all tasks. "We" (many people) will continue to want many tasks to run quickly. In many cases, speed will be more important than efficiency, and that's what this sub-thread is about. We're talking about what to do when you want speed.

Secondly, it just so happens that in the vast majority of cases, over 90% of CPU time is spent in a very small section of code called the "inner loop", which is the little chunk that runs many times.

Suppose you're adjusting a video in some way, maybe resizing it or changing the brightness. The video is a bunch of frames, each frame is a bunch of pixels, and each pixel is three color values, red green blue. There are 256 possible values for each of R, G, and B. The code looks like this:

for each of 200,000 frames
              for each of 800,000 pixels

CalculatePixel() gets called 320,000,000,000 times. (320 billion times). Each time, it's passed a value from 0-255 and returns a value from 0-255. Which means that the value for CalculatePixel(0) gets recalculated about a million times. Compare this code:

For x in 0-255
          Answer[x] = CalculatePixel(x)

for each of 200,000 frames
              for each of 800,000 pixels
                          pixel.red = Answer[pixel.red]
                          pixel.green = Answer[pixel.green]
                          pixel.blue = Answer[pixel.blue]

If you're in the habit of speeding it up by calculating all possible values for your inner loop, you code to take advantage of that fact. Here we can see that it's much more efficient to do the calculation 256 times rather than 320 billion times. This concept is generally true for most programs- the bulk of the CPU time is spent doing whatever the program does repeatedly. I routinely make other people's software faster amd more efficient using this type of approach.

A recent case was a security scanner, which did this:
For each IP -
        For each port
                  For each vulnerability

You can see that CheckPortForVulnerablity() was called over a billion times.

Comment Re:The Age of Cyberpunk with its Corporate Sociali (Score 1) 174

Insomniac ? I hope you don't have that regularly, if so I suggest you do something about that. Less caffeine and less stress ?

OK, I'll be the first to admit it. I'm no expert, I suggest you talk to one.

I'm also not completely sane at this moment, this is the morning after a night on the town, their is still a lot of alcohol in my body. ;-)

Anyway, about the topic at hand...

Yes, I do think about it like a pendulum as well and about how far it can or will be pushed in one way (maybe even multiple pendulums). I think most people would really want to avoid full on revolution. Because it's hard to predict the outcome. Take for example the Arab spring. Also look at ISIS/IS/ISIL/Daesh they came out of the chaos largely created by the US (but that is a whole different topic).

Maybe I'm wrong, but I think at least some people in government get it.

Sometimes when I see police in countries like the US get more and heavier arms, I'm thinking someone is preparing for that future in a very negative way.

But let's look at the positive.

Let's take for example the people that claim that automation will take our jobs:

Maybe they are wrong, but one thing is correct, technology can cause a lot of change and it probably will. Maybe even accelerate.

When talking about that, you'd always keep in mind what Voltaire said: Work saves us from three great evils: boredom, vice and need.

Then you look at what people in some governments are trying to do:

From a US perspective you'd think it's some kind of socialist system, but a lot of the ideas behind that came from the US from people like: Friedrich Hayek, Richard Nixon and Milton Friedman. Or as Andrew McAfee likes to say with a big smile: frothing-at-the-mouth socialists ;-)

In Europe we now have a bunch of organisations, countries and cities looking seriously into this and testing it in real life again.

From a pure technology perspective, I can see technology solving the need problem.

If energy prices do really keep falling like they have with capturing the energy from wind and solar light and heat then it will get easier (=cheaper). Take for example the Sahara Forest Project: https://www.youtube.com/watch?...

Energy storage is also still improving too: http://rameznaam.com/2013/09/2...

They seem to be on a Moore's Law like trajectory.

They might claim to be the first:

But automatic milking also has been doing very well for how long ? over 10 years now ?

If you combine: cheap energy, cheap clean water, cheap electronics/communication, cheap energy storage, cheap food production
you get a very potent mix to solve a large part of the problem of need that Voltaire talked about. In the documentary I linked they also talk about cheap health care (I hope so). Those are some very positive trends.

Cheap technology also seems to create a more decentralized future, so maybe in that sense Bitcoin/OpenBazaar and solar panels are similar.

I'm from Europe, I personally don't see the state as my enemy like some people in the US or some in Bitcoin do. For example I think of the government as the biggest VC funder/risk taker of them all. Who would spend more than 10 years on fundamental research with a high amount of risk of failure and then give it away for free (simple example: Internet, funded by ARPA now called DARPA. I don't know if it was considered a risky endeavour at the time, but it's an example of long term funding). And probably without the state no guaranteed minimum income either.

As usual, technology solves one problem and then causes to creates now ones too.

For example what if we start deplete our planets resources

I think growing inequality is a problem too, actually partly caused by technology. Look at most of the newly created really wealthy people they all came from technology companies. I think inequality might actually be partly the cause of our current shitty economies. The medium incomes haven't gone up.

Anyway, I could go on... but maybe this post is also long enough.


Online Museum Displays Decades of Malware (thestack.com) 12

An anonymous reader writes: archive.org has launched a Museum of Malware, which devotes itself to a historical look at DOS-based viruses of the 1980s and 1990s, and gives viewers the opportunity to run the viruses in a DOS game emulator, and to download 'neutered' versions of the code. With an estimated 50,000 DOS-based viruses in existence by the year 2000, the Malware Museum's 65 examples should be seen as representative of an annoying, but more innocent era of digital vandalism.

Comment Re:Ubuntu (Score 1) 44

The point is pulling an application.

How the people that made the docker image you are using created their Docker image doesn't matter much.

You can still use Debian/Ubuntu as the base of _your_ Docker images.

These are just the official Docker images. I can see how that makes sense for something like a MySQL Docker image. You just want it to run the database server.

Comment Re:Advisors? (Score 1) 67

I don't understand why the term financial advisor is used when they are just salesmen. What advice do they provide other than, "you should definitely buy our products", or maybe, "I would advise you against closing your account with us"?

There is more to it than that.

How to Choose a Financial Planner

Look for a financial adviser who is a certified financial planner (CFP). They're licensed and regulated, plus take mandatory classes on different aspects of financial planning. . . . Financial planners advise clients on how best to save, invest, and grow their money. They can help you tackle a specific financial goal—such as readying yourself to buy a house—or give you a macro view of your money and the interplay of your various assets. Some specialize in retirement or estate planning, while some others consult on a range of financial matters.

Don’t confuse planners with stockbrokers — the market mavens people call to trade stocks. Financial planners also differ from accountants who can help you lower your tax bill, insurance agents who might lure you in with complicated life insurance policies, or the person at your local Fidelity office urging you to buy mutual funds.

Anyone can hang out a shingle as a financial planner, but that doesn’t make that person an expert. They may tack on an alphabet soup of letters after their names, but CFP (short for certified financial planner) is the most significant credential. A CFP has passed a rigorous test administered by the Certified Financial Planner Board of Standards about the specifics of personal finance. CFPs must also commit to continuing education on financial matters and ethics classes to maintain their designation. The CFP credential is a good sign that a prospective planner will give sound financial advice. Still, even those who pass the exam may come up short on skills and credibility. As with all things pertaining to your money, be meticulous in choosing the right planner. . . .

A growing number of financial planners make money only when you pay them a fee for their counsel. These independent financial planners don’t get a cut from life insurers or fund companies. You might pay them a flat fee, such as $1,500, for a financial plan. Or you could pay an annual fee, often 1% of all the assets—investment, retirement, college-savings and other accounts—they’re minding for you. Others charge by the hour, like lawyers. . . . more

Comment Re:Not a bad deal, really. (Score 1) 100

take the look to independently investigate the research that has been done in this area. There is a lot of bullshit, but there is also work that has never been refuted—work whose significance level is such that it is above and beyond anything except it is adequate in any other area

Please link to this, I am not aware of such research.

Comment Re:Is this worth my time? (Score 1) 67

I stopped when I hit the 7% and I realize I'm just some guy on Slashdot. 7% is fine, nice and safe, and smart. Don't touch it. Don't fiddle with it, don't poke buttons, don't start watching the financial news, don't start reading the industry magazines, don't start doing you own work and watching stock tickers. Don't do it...

If you do do it then don't be greedy and get out when you can - but make sure to invest long-term (depending on what you're doing) as you're taxed at a lower rate. So, find a few interesting companies and dump a chunk into them and just sit. Wait a year and keep sitting. It'll spike unless you picked wrong. Do not even watch the tickers or check the prices. Set your sell price, this can be done automatically, and then just do it again.

However, take your 7%. 13% is not too much to ask for but pay attention to the do not be greedy part. I mean that. With the latter, set it at a crazy number and wait. Put it this way, I bought 2000 shares of Tesla when they were at about $24. They've not yet hit the price where they'll be unloaded automatically. (I adjusted the number - up.) However, there's a certain sell-by date (announcement, actually) for me. I'll bail then and have made a very tidy profit. I'm not actually sure what today's prices were and I'm not gonna bother looking. You can do the math yourself if you'd like.

Comment Re:And who trusts Financial "Advisors"? (Score 1) 67

Also important, the goal isn't to beat a PRNG. The goal is a steady increase in profits with diversity and a good long-term investment strategy that will make your money work best for you in the long run. It's a race, that's true. It's an endurance race, not a sprint. Now that I kind of know what I'm doing, I regularly exceed the growth done by my investment manager - I've two portfolios, one is the one I "play" with. However, to make the percentages I make, I need to take risks that I'd fire my investment manager for taking.

Slashdot Top Deals

It was kinda like stuffing the wrong card in a computer, when you're stickin' those artificial stimulants in your arm. -- Dion, noted computer scientist