Please create an account to participate in the Slashdot moderation system

 



Forgot your password?
typodupeerror

Comment: Re:Help me out here a little... (Score 2) 533

by slew (#49506999) Attached to: Utilities Battle Homeowners Over Solar Power

That would work if the power distribution network was ideal and didn't have any resistance/reactance.

In real-life, the spike from all the solar installations would cause network instability unless controlled distributively (i.e. measured and limited at the spike sources). The question of who would pay to maintain that type of system is one of the major issues that needs to be solved. Of course the people who pay for solar want to shove all the power they can back on the grid to help subsidize their costs, so it unfortunately, isn't in their best interests to limit power to promote grid instability (unless they would be causing electrical fires on their own property/equipment), and the power company wouldn't want to help people cut the cord, so here we are...

Comment: Re:And once this school fails to get women interes (Score 1) 599

Can we drop the pretense that "computer science" in high schools is nothing more than programming and turning out code monkeys.

In my experience, "computer science" in high school wouldn't even qualify anyone for being a code monkey...

If by high school you haven't taught yourself programming, you aren't going to learn it taking a class in high school or community college or even university well enough to code yourself out of a paper bag.

If you finally do learn programming later in life, it will probably later when you actually have a job (or if you are one of those recent folks that are learning to code in a boot-camp).

Comment: Re:Feminism ruins society again... (Score 1) 599

I doubt that the STEM program at the mixed school my son would have to go to if I lived in this district will be on par with the shiny new facilities at the new school that specializes in STEM (for girls). Separate...but I doubt equal.

Since this is the LAUSD, perhaps of those schools will probably get those ipads with pearson software... Since they aren't buying that stuff anymore, maybe the larger population will get something "better"...

I don't put much faith in the LAUSD in making this type of school work. If I were in the district, I wouldn't be opposed on the grounds that it is unequal opportunity for boy/girl students, but that it's likely to be a FUCKING WASTE OF MONEY that could be better spent elsewhere...

On the other hand, sometimes, you might just win, by losing.

Comment: Re:I thought we were trying to end sexism? (Score 1) 599

Sexism isn't just excluding or discriminating, there is one other vital component: harm. It's like having a girl's bathroom and a boy's bathroom. The girl's bathroom might even have more facilities (tampon machines/disposal). It's not sexist because it doesn't disadvantage either gender, it's simply discriminating for a perfectly legitimate reason.

Unless someone can show that this school will somehow harm boys then it isn't sexist.

It may not be sexist, but it might be illegal. Title IX, explicitly prohibits excluding students from participation in or the benefits of ANY education program or activity receiving federal financial assistance.

The most issue addressed by Title IX is spending money supporting a football and wrestling teams (which is predominately boys). Title IX pretty much says if you spend that money there, you have to spend an *equivalent* amount of money providing sports opportunities for girl on the grounds that in a zero-sum game of money, girls are *harmed* because you spent that money on something that only benefits boys.

Of course things cannot be totally equal in every situation, so there is a 3-part test to be evaluated

1. percentages of M/F students in an activity (e.g., like sports) that accepts federal funds are about the same as the student population (this is the easiest way to show compliance)
2. equal opportunity exists for M/F students in that activity (very hard to show if you exclude 1 gender), OR
3. school is fully providing opportunities that meet the interests and abilities of M/F students

I suspect where this whole things falls downs is #3. By excluding boys from this STEM program and only providing a Language Arts option for boys if there is a significant number interested in STEM (I'm guessing, there are quite a few of them), I don't think this will survive an equitable legal challenge (imagine if it were the reverse). Having said that, legal challenges today are intertwined with politics and judicial activism, so it's hard to say what the result actual legal challenge result might be.

Comment: Re:You Can See (Score 1) 113

by slew (#49489743) Attached to: An Engineering Analysis of the Falcon 9 First Stage Landing Failure

Although I'm willing to take it on faith that it might be 'stiction' on the actuator side, I'm pretty sure extreme variations which can cause unanticipated phase lag from a measurement system (say a gyro or a flow meter) is equally disruptive to a control system and can generically explain control system oscillation events as well.

Sometimes you never really know until you set up the conditions and simulate the crap out of it in an controlled testbed as it is much harder to distinguish the difference in a "live" situation.

Comment: Re:Wow. Just wow. (Score 1) 325

by slew (#49489127) Attached to: LA Schools Seeking Refund Over Botched iPad Plan

To be fair, they can't really run a controlled experiment on an individual patient, so they have to do some guessing.

That's why they call it *practicing* medicine...

But seriously, most doctors (esp pediatricians) simply follow protocols. For example, see a certain progression of symptoms, combine with a little patient history and what they have observed during their time in the field, and then proscribe a course of action associated with that, and monitor to adjust course. That's the protocol.

Doctors aren't generally doing anything remotely scientific unless they happen to be experimenting on your kids with an untested protocol, (which sometimes happens), or perhaps if they are trying to get a complaining parent out of their hair (but even though that might be an experiment, it's generally w/o a control group which isn't very scientific)...

Comment: Re:No I don't agree (Score 1) 341

Proportional Integral Derivative (a very primitive type of feedback loop controller that modifies the control input a fraction proportional to the error signal, another fraction relative to the integrated/smoothed error signal, and yet another fraction relative to the first derivative of the error signal). In the old days people spent lots of time "tuning" these fractions (e.g., like ziegler nichols) to get acceptable performance.

I suspect they don't use anything this primitive in their control loop (at least I hope they don't). That's control-systems 101 in college before you get to smith controllers and state based systems feedback (which is also quite primitive)...

Comment: Re:Sounds like internet.org is offering (Score 1) 75

Apple seems to offer quite a spacious jail with lots of useful apps/amenities.
They also seem to charge more for the experience.

If you can offer an attractive cage at a discount, maybe no one will care they are in a white-washed cage instead of a gilded cage...

Comment: Re:We have already figured most of this out. (Score 2) 363

by slew (#49472989) Attached to: Can Civilization Reboot Without Fossil Fuels?

Asphalt is aggregate (usually crushed rocks) stabilized with petroleum tar products. Concrete on the other hand uses similar aggregate, but is bonded with cement (often portland cement), which although doesn't contain petrol products, but takes a lot of energy to mine and kiln fire which gives it a large carbon footprint which is only partially offset by the fact that during the "setting" process, cement actually absorbs carbon dioxide from the air (converting calcium-hydroxide into hard interlocking calcium-carbonate crystals).

FWIW, they already have a way to make asphalt equivalent material by replacing tar with pine-rosin and pitch.

Comment: Re:C64 had a cassette drive (Score 1) 74

by slew (#49464847) Attached to: 1980's Soviet Bloc Computing: Printers, Mice, and Cassette Decks

You never had a 3.25" floppy. You mean 3.5".

Perhaps you are talking about an ANSI X3.171-1989 90mm drive? ;^)

Which some people in the UK occasionally called a 3.5" "stiffy" to distinguish it from its larger/floppier predecessor like the 8" floppy and the 5.25" mini-floppy...

FWIW, although I never personally had a 3.25" drive, one of my buddies did purchase the Amdisk 3" compact floppy disc system for his Apple ][+....

Comment: Re:China's current capability (Score 1) 229

by slew (#49452031) Attached to: US Blocks Intel From Selling Xeon Chips To Chinese Supercomputer Projects

Although you may be in the field of chip design, you don't appear to be as knowledgeable about the field of sino-taiwanese politics. Given the politics of the folks in charge at TSMC, I'm not sure they would side with China over the USA. Many of them exited China during the cultural revolution and generally have a dim view of the Mainland.

In fact, the chairman of TSMC (morris chang, a harvard, mit, stanford alum) cut his teeth in the semiconductor business in the USA (in TI and General Instruments) before being recruited back by the Taiwanese government to found TSMC. Other than being born in mainland china, he's about as American as you can get (fwiw, he was also the guy in charge of bringing us TI's wonderful speak-n-spell). He's also on record supporting the Wassenaar Arrangement even though Taiwan isn't a signator, and I think I remember hearing that most of his daughters attended school and live in the US.

Comment: Re:I would have to assume... (Score 3, Insightful) 117

that the "accurate within microns" part is only applicable if you feed it some scaling information.

Otherwise, it's going to only be as accurate as the person guessing the size of the original.

AFAICT, the technique used by this imager is FMCW (frequency modulated continuous wave) which basically give you a very accurate time-of-flight measurement. In this type of system, the received optical frequency difference from the transmitted frequency is measured by optical-coherent mixing and sensing the resultant beat signal frequency. Apparently this groups contribution to this technique is to measure both the phase and amplitude of this beat signal digitally so multiple algorithms can be deployed to analyze the beat signal.

In any case, given a very accurate distance to an object, the solid angle projection to the imaged object, and some basic optical system calibration data, it is presumably fairly straightforward compute the actual size of the object w/o guessing.

Comment: poor reporting... (Score 0) 166

by slew (#49418865) Attached to: The Arrival of Man-Made Earthquakes

This isn't the "arrival" of man-made earthquakes. Ever since man has been doing large scale environmental modification, we have been inducing seismic activity.

The most common induced seismic events occur when we build dams to create reservoirs. One of the first examples was the filling of the Oued Fodda Dam in 1933. Others occur due to depletion of underground reservoirs (like the Lorca earthquake in 2011) or enhanced geothermal energy extraction (Cerro Prieto in 1979).

Of course all phenomena is new to the non-research reporting that passes for news today. The only difference is that today the perpetrators are seeking evil oil rather than life giving water or "renewable" energy...

Comment: Re:Yeah, Heh Heh (Score 4, Interesting) 167

We probably would have just spent considerable resources carpetbombing and firing battleship guns at them, long before setting foot on any of the main Japanese islands.

Probably should review your history. The short story, the US dropped the bomb to win the peace, not the war...

By the time the US dropped the bombs, they had *already* spent considerably resources firebombing Tokyo (including "Operation Meetinghouse" in March which was bigger than Dresden) to the point that most military commanders thought that there were no more high-value targets left in the city target (and other cities were then targeted). This was long before the nuclear bombs which were detonated in August...

I think many professional historians have become to realize that it was actually unnecessary to actually drop the bomb to conclude the war (it could have ended in a war of attrition as Japanese industrial war output had estimated to have dropped 90% from January to June of 1945), but the capitulation of the military was unlikely before the Russians would have become engaged in the Pacific War. The bomb was essentially dropped to hasten the end of the war to end the Pacific Theater War on the US terms (rather than risk a negotiated eastern block situation that occurred in Europe in the aftermath of the war).

Historical documents indicate that Prince Konoye was already favoring ending the war in February due the on-going strategic bombing campaigns which were devastating the country and the Emperor was favoring ending the war after the "Meetinghouse" firebombings in March, but the military rejected US requests for unconditional surrender until after the A-bombs were dropped in August. FWIW, Russia declared war on August 8th and invaded Manchuria on August 9th (3 months after the war in europe concluded as agreed to by Stalin in Yalta and coincidentally the same day the 2nd bomb was dropped).

Comment: Re:Here's the thing (Score 1) 227

by slew (#49394337) Attached to: Google 'Makes People Think They Are Smarter Than They Are'

And, then presents themselves as an expert on the subject because of that "fact".

Which is actually the real problem. Just because you possess a specific fact about a subject, why should I consider you an expert? You can present yourself as an expert all you want, but I don't have to accept that.

Basically, I ask myself, since you are generally only considered an expert if you are in possession of a comprehensive amount of knowledge from authoritative sources, why is googled information authoritative, or even comprehensive?

That doesn't mean that looking things up and presenting an argument based on that isn't applying well known principals of rhetoric in their arguments or statements.

It is of course quite possible to make a coherent and persuasive argument with the kind of limited factual information you might get by 2 seconds of google-ing (e.g., not from an expert point of view), but that art is lost on the interwebs (where somehow somehow asserting artificial "expertise" is bandied about as a way to attempt to suppress detractors from your poorly defensible positions).

I don't think this is at the same as those thinking they are actually experts ala-Dunning-Kruger (except perhaps to those who are naturally self-deluded which is probably a non negligible subset of people)...

e-credibility: the non-guaranteeable likelihood that the electronic data you're seeing is genuine rather than somebody's made-up crap. - Karl Lehenbauer

Working...