Beta

Slashdot: News for Nerds

×

Welcome to the Slashdot Beta site -- learn more here. Use the link in the footer or click here to return to the Classic version of Slashdot.

Thank you!

Before you choose to head back to the Classic look of the site, we'd appreciate it if you share your thoughts on the Beta; your feedback is what drives our ongoing development.

Beta is different and we value you taking the time to try it out. Please take a look at the changes we've made in Beta and  learn more about it. Thanks for reading, and for making the site better!

Comments

top

How Japan Lost Track of 640kg of Plutonium

taiwanjohn Re:Come now. (104 comments)

According to another post this plutonium could not be used to make a bomb, and the explanation makes sense to me. So even if they change the constitution they won't be making any bombs, at least not with this plutonium.

about three weeks ago
top

How Japan Lost Track of 640kg of Plutonium

taiwanjohn Re:Come now. (104 comments)

I was thinking some hardliners in Japan's military might have stashed it somewhere, "just in case" it's ever needed.

about three weeks ago
top

Making an Autonomous Car On a Budget

taiwanjohn Re:Oh Joy! (61 comments)

Fully automated vehicles, that is.

I don't think "full auto" is required. This is more like Tesla's "autopilot" concept than Google's "driverless" car. This would get used most often on the interstate, not so much in cities, and it's a pretty good fit for that application. I can do some work (or take a nap) between cities and take the wheel a few minutes before the exit ramp. (Or I could program certain conditions such as weather or traffic to trigger an alarm.) But even this level of automation would dramatically reduce highway casualties.

What I'm curious about is how they sense certain road conditions, such as "black ice" that can fool even the most experienced human driver. OTOH, with a broad range of sensing like RADAR and echolocation, you could plow through pea-soup fog without much worry.

cabs are too expensive for everyday use

I'm lucky to live in a place (Taipei) where public transportation is cheap and ubiquitous. Even taxis are plentiful and cheap here. I don't even own a single motorized vehicle. Why bother, when I can get to anyplace I want with less than 20min walking and $2 in fees, and I can get home from anywhere in the city for less than $10, anytime, day or night?

This is where "full auto" is required: bringing this kind of convenience to the broad, "midwestern" spaces of America. When you can make the round-trip to/from your local watering hole for less than 15 bucks, why would anyone take the risk of driving drunk?

I think Google is smart to be investing so heavily in this tech, because once we pass that tipping point, this is going to be the biggest "killer app" of all time. And in the meantime, Tesla is also smart to be pursuing their autopilot tech, because it will be a huge selling point.

about a month ago
top

'Godfather of Ecstasy,' Chemist Sasha Shulgin Dies Aged 88

taiwanjohn Re:And for those that weren't aware (164 comments)

I read somewhere, years ago, that Shulgin had an "informal understanding" with the authorities: he would keep his "recipes" obscure enough to prevent casual duplication by anyone without a PhD in organic chemistry, and in return "they" would leave him alone to do his work -- and they would also reap the benefits of his research via his copious and detailed lab notes and trip reports.

I have no idea if this is true, but it sounds nice.

In any case, well played, Sasha... RIP.

about 2 months ago
top

Google To Spend $1 Billion On Fleet of Satellites

taiwanjohn Re:180 satellites... (170 comments)

Based on past satellite ventures, costs could rise.

Based on recent developments, costs could plummet. IMHO, the only reason Google is even talking about this now is because SpaceX recently flew a (theoretically) reusable first stage. Of course, "practical" reusability is still in the works, but Musk is tight with the gurus of Google, and it doesn't cost them much in the short run to flog their "visionary" quest to bring broadband to the masses. And if Musk succeeds with reusability (which seems likely) they'll be able to deploy this constellation at a fraction of the currently advertised cost.

Sounds like a win-win for all concerned...

about 2 months ago
top

SpaceX To Present Manned Dragon Capsule

taiwanjohn Re:Excellent! (128 comments)

> SpaceX want to remove the parachutes, too?

No, they are not removing the parachutes, they'll be kept as a backup system in case the landing thrusters fail.

about a month ago
top

Robots Will Pave the Way To Mars

taiwanjohn Re:Ad astra per aspera (95 comments)

It'll be a while before we start towing asteroids into Earth orbit. Earth-Moon Lagrange points will be the first destinations, then after we get good at that we'll gradually allow more and bigger rocks closer to Earth.

As for kinetic bombardment from orbit, the energy budget is not promising for this scenario. The amount of reaction mass needed to de-orbit a large boulder is "non trivial" to say the least. I suppose you could build a rail-gun and shoot a small mass at high velocity in order nudge a bigger rock into decay, but unless you've got a really huge capacitor, you'll have a tough time "dropping" a rock from orbit that would do much more damage than a standard cruise missile.

It's trivial to track such changes in velocity. So if you can't "drop" your boulder directly on target without taking a couple of orbits to decay, then the weapon loses it's surprise/initiative. The target could simply nuke it in space before it has a chance to de-orbit.

Then you've got the problem of cross-range deflection. Unless you don't mind waiting a few hours (or days, or weeks) until your rock's orbit takes it right over your target, you're going to need some way to widen your zone. The rail-gun can do some of this work, but you're going to need an "aerodynamic" rock in order to hit a precision target.

I'm not saying this is impossible, I just don't think it's very likely, given how many other (much easier) ways we already have to do the same job.

about 2 months ago
top

Robots Will Pave the Way To Mars

taiwanjohn Re:Send In the Clones (95 comments)

If you're not familiar with potholer54 you should check out his videos on climate change. He cuts through the BS/hype on both sides of the issue, and is reasonably amusing too. Very worth the time.

about 2 months ago
top

Robots Will Pave the Way To Mars

taiwanjohn Re:What about it? (95 comments)

Mod points can't be changed, only deleted. Could be somebody accidentally down-modded somewhere else in this discussion, and posted with their real uid to undo the mistake. If they had previously up-modded the parent, that mod point would be gone now too.

about 2 months ago
top

Fusion Power By 2020? Researchers Say Yes and Turn To Crowdfunding.

taiwanjohn Re:Bad move (280 comments)

Thanks again for "translating" the argument into language I can make sense of. IIRC, Lerner does acknowledge the engineering challenges in the "PCST" (nice acronym, btw). But if he can demonstrate the p-B reaction with his method (especially if he can do so for $200k), that could open a floodgate of interest and investment.

Doing that reliably on an over-unity energy budget would be a "BFD" (in the words of VP Biden), and it could dramatically alter the course of R&D. I'm just "spit-balling" here as a non-expert, but the PCST sounds a lot less challenging than the Tokamak.

about 2 months ago
top

Fusion Power By 2020? Researchers Say Yes and Turn To Crowdfunding.

taiwanjohn Re:Bad move (280 comments)

That is interesting. Thanks for the link. I wish I had the expertise to follow the argument in detail, but I'll just have to take "their" word for it (on both sides) and wait and see how it all turns out.

That said, I confess that I hope Lerner can make his method work. From an engineering POV, it's an elegant solution to the problem of plasma instability... don't fight it, use it to your advantage. The history of science may be littered with "elegant" ideas that didn't pan out, but there are also quite a few examples of ideas that were initially scoffed at by the mainstream, and nowadays are mainstream.

about 2 months ago
top

As NASA Seeks Next Mission, Russia Holds the Trump Card

taiwanjohn Re:So many mistakes. (250 comments)

If that is the case, then why haven't they done a single experiment in centrifugal "artificial gravity" yet? Heck, they wouldn't even need ISS for that. The idea has been around since the 60s (at least), but it's never even been tried by anyone that I know of.

about 2 months ago
top

Fusion Power By 2020? Researchers Say Yes and Turn To Crowdfunding.

taiwanjohn Re:Bad move (280 comments)

Part of the problem is that Mr. Lerner also favors a steady-state model over the Big Bang theory, so he is not taken seriously by the mainstream scientific community. OTOH, he does appear to know a lot about plasma behavior, and has gotten some interesting results with the small-scale "garage" experiments he's done thus far. If $200k is enough to get his work to the next level where he can show some more compelling evidence, maybe that will be enough to get some VC guy like Khosla to give him a few million more.

In any case, he seems harmless enough. And he doesn't appear to be blatantly trying to rip people off, like so many of these "free energy" gurus... I say let him proceed, and see what he can come up with.

If you're curious about the approach, watch his Google Tech-Talk for the details. It's one of the more novel methods I've seen.

about 2 months ago
top

Autodesk Unveils 3d Printer As It Aims To Become Industry's Android

taiwanjohn Re:They make their money off of software. (85 comments)

Probably the printer driver will come on a disc with some autodesk demos that you can pay-to-unlock.

If the price to "unlock" the demos is cheap, they might have a winner, but then why would their current customers continue to pay those hefty per-seat fees? OTOH, if they're going for a mass-market shift toward cheap, ubiquitous 3D printing, that would make sense. I just don't see how a big corporation would make a move like that on such a short time scale. Methinks this is more marketing hype than a real strategic shift.

about 2 months ago
top

Autodesk Unveils 3d Printer As It Aims To Become Industry's Android

taiwanjohn Re:They make their money off of software. (85 comments)

I was thinking the same thing. And this breaks down their analogy to the Google Nexus, since Android was released as "free" and (reasonably) "open" software. OTOH, if you can afford a $5k printer, you can probably afford a "seat" license for AutoCAD too. Seems to me the maker-bot crowd have already sparked the fire, so I'm not sure how this new offering is going to speed up the revolution. I don't see anything wrong with what they're doing either... just have to wait and see what comes of it.

about 2 months ago
top

Astronomers Identify the Sun's Long-Lost Sister

taiwanjohn I vote we name it... (69 comments)

Lady Marmalade

Hey Sister, Go Sister, Sol Sister, Go Sister
Hey Sister, Go Sister, Sol Sister, Go Sister

about 3 months ago
top

Tesla Logged $713 Million In Revenue In Q1 and Built 7,535 Cars

taiwanjohn Re:Down 3%?! (131 comments)

Today's /. fortune is particularly appropriate: "There has been a little distress selling on the stock exchange. -- Thomas W. Lamont, October 29, 1929 (Black Tuesday)"

about 3 months ago
top

US Climate Report Says Global Warming Impact Already Severe

taiwanjohn Re:sigh (627 comments)

why hasn't anyone proposed this mysterious solution if it fixed the problem that "easily", with "barely any significant change in our style of life"?

Someone has proposed a solution. Actually, more than one solution.

The first video is Amory Lovins giving his presentation Reinventing Fire. This is a detailed plan for eliminating all fossil fuel emissions by 2050 for no greater cost than business as usual.

The second video is Allan Savory showing how to sequester vast amounts of CO2 by reversing desertification with managed grazing of livestock.

Both of these solutions are already happening in many places, it's just not common knowledge yet.

about 3 months ago
top

You Are What You're Tricked Into Eating

taiwanjohn Re:Sugar (499 comments)

For the most part, yes. But if it travels such a long distance it's more likely to be picked early and "ripened" in transit. Also, supermarket produce is more likely to be treated with pesticides, herbicides, etc.. Your best bet is either to grow your own or get to know your local farmer.

about 3 months ago
top

You Are What You're Tricked Into Eating

taiwanjohn Re:Sugar (499 comments)

...is also a major culprit in this story, in part due to the "low-fat" orthodoxy that developed in the 1970s. When you take out the fat, you lose a lot of the flavor, so sugar was used to make processed foods more appealing. Even worse, hydrogenated vegetable oil was used as a fat replacement. (Turns out that saturated fats are not as bad as they thought back then.) Another problem with processed foods is that they contain far less fiber, since removing the fiber is an easy way to extend shelf life. But this affects the way they are digested and absorbed, exacerbating the bad side effects.

Dr. Robert Lustig has an excellent lecture about sugar and how it is the single most important change in our diet in the last few decades, and the chief cause of rising obesity and diabetes rates. (The above link is a TED Talk, he also has several long format lectures available on YouTube.)

The author Michael Pollan has a simple set of 3 rules for managing your nutrition: 1. Eat food*; 2. Not too much; 3. Mostly plants.

* What he means by this is "real" food, rather than the "edible food-like substances" that constitute the bulk of the American diet. He has a simple rule for identifying real food: If you've ever seen it advertised on TV, it's probably not real food. Also, for various reasons, there is an inverse relationship between the "realness" of food and the distance it travels from its source to your plate.

about 3 months ago

Submissions

top

Nate Silver's new site stirs climate controversy

taiwanjohn taiwanjohn writes  |  about 4 months ago

taiwanjohn (103839) writes "One of the first articles on Nate Silver’s highly anticipated data-driven news site used flawed data to make its conclusions, according to some of the nation’s top climate scientists.
Silver’s FiveThirtyEight published its first article about climate change on Wednesday, entitled “Disasters Cost More Than Ever — But Not Because of Climate Change.” But climate scientists are condemning the article and its author, Roger Pielke Jr., saying he ignored critical data to produce a “deeply misleading” result.
The crux of Pielke’s article is this: Extreme weather events are costing us more and more money, but that is not because climate change is making extreme weather more frequent or intense. The reason we are losing more money, rather, is because we have more money to lose. Pielke came to this conclusion by measuring rising disaster damage costs alongside the rising global Gross Domestic Product. He also cited a U.N. climate report, along with his own research, to assert that extreme weather events have not been increasing in frequency or intensity."

Journals

taiwanjohn has no journal entries.

Slashdot Account

Need an Account?

Forgot your password?

Don't worry, we never post anything without your permission.

Submission Text Formatting Tips

We support a small subset of HTML, namely these tags:

  • b
  • i
  • p
  • br
  • a
  • ol
  • ul
  • li
  • dl
  • dt
  • dd
  • em
  • strong
  • tt
  • blockquote
  • div
  • quote
  • ecode

"ecode" can be used for code snippets, for example:

<ecode>    while(1) { do_something(); } </ecode>
Create a Slashdot Account

Loading...