Slashdot is powered by your submissions, so send in your scoop

 



Forgot your password?
typodupeerror
Check out the new SourceForge HTML5 internet speed test! No Flash necessary and runs on all devices. ×

Comment Re:I thought diesel ran cleaner (Score 1) 65

Typical compression ratio in a Diesel engine is somewhere around 20:1, vs a gasoline engine that's running 10:1 or there about.

So what?

Basically this is displacement/cylinder * compression ratio * RPM * number of intake strokes per revolution.

The compression ratio is a function of the head volume and the cylinder volume. It has nothing to do whatsoever with determining how much air is drawn into the engine, which is defined by speed, bore, stroke, and intake efficiency. It is rather determined by how much air is drawn into the engine, and how much space you have left for air at the end of a compression stroke.

Ever wondered why diesel tail pipes are a lot larger than gasoline ones? This is why, diesels move a lot more air.

Diesel tail pipes are a lot larger than gasoline ones because diesels shit the bed when you have backpressure. It ruins their efficiency and you have to play tricks to get it back. Turbocharging is worth it anyway because it's turbocharging. Now, pay attention to this part, because it's important: exhaust gas volume is proportional to load. Diesels have bigger exhausts because they have more torque. This is also why turbochargers and diesels go together so well. Turbochargers are driven by exhaust gas expansion, which as mentioned, is proportional to load.

If you carve the piston out, you lower the compression ratio, and you increase the amount of air the engine consumes. You in fact have this exactly backwards.

Comment Re:I thought diesel ran cleaner (Score 1) 65

Not when cruising at 65 mph. Not even close.

Well, tell us what it is. Neither of my turbos boost that high, but they're both old. (My F250 peaks out at 11 psi and my Mercedes at 12.) The F250 cruises at only around 2 psi unless you have a trailer, then it's more like 6 or 7. The Mercedes cruises at around 7 or 8 psi. But they have much lower boost pressure than modern diesels.

Comment Re:So much for biodiesel use... (Score 1) 65

And still has a hell of a lot of particulate emissions, negatively impacting air quality in major cities, which you might note are the entities banning the diesels here.

Gasoline has just as much particulate emissions as diesel. It's just a smaller soot particle which we couldn't accurately measure until recently. Of course, DPFs on diesels reburn the soot until it's a small, invisible particle just like gasoline, making it just as dangerous as gasoline.

Banning diesel is not the remedy. Banning combustion is the remedy. Banning diesel is just stupid.

Comment Re:Democrats are the enemy (Score 1) 549

They're all going to agree to never lobby for foreign entities, and go half a decade after they leave office before they can do that work domestically.

Guess what? Those agreements are unconstitutional and won't stand. That's like a Californian signing a non-compete agreement. Okay! Sure!

Comment It's already happened a few times already... (Score 1) 287

"Secretary" used to be the most common job according to some interpretations of BLS reports. The Word Processor made that role largely obsolete and now self-service:
http://www.npr.org/sections/mo...

So nowadays it's "Truck Driver"... wait a bit longer until autonomous vehicles make those delivery jobs go away. Wouldn't call those middle-class jobs, though.

Counterpoint: Sales and Services are the most common job in the US today, along with maybe some form of Educator:
http://www.marketwatch.com/sto...

It'll still be a while before those social jobs are automated away.

Comment Re:OK, now pull the other one (Score 1) 488

Actually, it's nowhere near that simple. For example, my wife is a "stay-at-home mom". Thus she's on the "bad" side of the labor force participation rate.

The numbers of "stay-at-home moms" includes women who are doing it because they cannot find work.

She's doing this because 1) we think it's better for our younger-than-school-age kids, and 2) she can't make enough to pay for the daycare we would have to buy.

She chose to be unemployed rather than underemployed? Thank you for making my point for me.

Comment Re:Plenty of low-wage jobs to go around... (Score 1) 488

Well, I have no great love for CNN, but I liked the look of this article. Let's see, there's a Forbes link on millenial underemployment, let's skip that one just in case. Hmm, there's an article on Monster with... no date? hmm, can't cite that. Here's one from time which says 46% of Americans Say They Are Underemployed, that's a fun idea. The federal reserve's estimate is "fairly close to the trend derived from CPS data, but at a much higher level".

IOW, the direction of trend is accurate, but the numbers are bullshit. Like always

Comment Re:I prefer emby... (Score 1) 81

I have just read about emby after reading your comment, and it has made me excited. Not in the TMI way, but in the this might be what I am looking for way, even though it depends on Mono. I'm going to download an Ubuntu image for my Pine A64+ stat. Hopefully that has enough gusto to do what I want to do with it. The data is already connected to the network via another ARM SBC (a pogoplug) which also has GigE.

Comment Re: If a drone came in your yard uninvited ... (Score 1) 44

"Nobody knows where all these cool drone parts came from. There's a chassis over there in the dumpster of the Shell Station on Richmond Street with a scratched off label. Nobody know how it got there."

No doubt if nobody saw you do it, you're golden. On the other hand, Slashdot is going to get a subpoena for logs if someone actually does find a scratched off label in the dumpster of the Shell Station on Richmond Street one day...

Comment Re:Koran 9:29 (Score 1) 371

Well, not entirely. I mean sure, it's fine to stone to death those who worship false idols etc. But if you're not from the right tribe, you can never become one of God's chosen people. So, you're basically boned either way.

Actually, that's part of the point of Christianity, as opposed to Judaism. If your mom isn't a registered Jew, neither are you. But anyone can become a Christian and even go to Christian heaven if they just repent their sins and accept Jesus into their heart at the last minute. Jews also expect you to do certain things while you're alive if you want to be favored by God when you're dead, and so do the Muslims. The Christians are the only ones for whom belief is sufficient. In that way, if in no other, Christianity is less bigoted than its fellows.

You don't have to be a six footer...

Comment Re: I peruse iffy websites all the time (Score 1) 371

Oddly enough, those three chemicals are also very useful to etch PCBs. But thanks to our SWAT team, I now know an additional use for them...

This is the kind of thing that drives me nuts. What year is it? Can't they just look up your blog and find out you're making whosiewhatsits with homemade pcbs? Who knows, maybe this was a while ago. But that sort of thing is still going on.

Slashdot Top Deals

1.79 x 10^12 furlongs per fortnight -- it's not just a good idea, it's the law!

Working...