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Ask Slashdot: What Tech Products Were Built To Last?

john.r.strohm Timex Ironman Triathlon 200m digital watch (702 comments)

I just retired a Timex Ironman Triathlon 200m digital watch. It was time for a battery (at least its third, possibly its fourth), when I noticed that the Mode button had failed. (I never use it as anything but a watch these days, having pretty much given up diving.) That watch was easily 15 years old, and had been at least 100' underwater (wreck diving off North Carolina).

That watch was the cheapest diver's watch you could buy, by a big margin. Timex was very careful NOT to call it a diver's watch, because of product liability concerns, but IN FACT that's what it was and a lot of people used it for diving. (On their 50m and 100m water-resistant models, Timex very carefully said that the water resistance was guaranteed only as long as no buttons were pushed, and they very carefully did NOT say that for the 200m models. That language has since changed.)

about 4 months ago

Team Austria Wins the 2013 Solar Decathlon With Their Net-Zero LISI House

john.r.strohm I Must Have Missed Something (50 comments)

I looked at the slideshow on the LISI house site, and I don't see anything that looks like a kitchen, anything that looks like a bedroom, or anything that looks like a bathroom.

Yes, they made a pretty space, but I do not see how it is a space for people to live, and I thought that was the purpose of a house, to be a space for people to live.

about 10 months ago

NSA Chief Built Star Trek Like Command Center

john.r.strohm Re:That's awesome (372 comments)

VERY old news.

When "Star Trek" first came on the air, in the 1960s, the US Navy sent a team to visit the set. They were building a new communications center, and they REALLY liked the bridge set layout, as it did an OUTSTANDING job of facilitating communications among the bridge crew.

about a year ago

US Uncorks $16M For 17 Projects To Capture Wave Energy

john.r.strohm Re:Hope they pay close attention (132 comments)


NOBODY wants to talk about this one.

Extract all the energy from the wave, and you have no more wave. There is a HUGE amount of shoreline and shallow-water marine ecology that is critically dependent on wave action. Remove the waves, and you wreck that ecology.

The Environmental Impact Statements for those wave energy plants are gonna be INTERESTING.

about a year ago

Man Builds Fully-Functional Boeing 737 Flight Simulator In His Son's Bedroom

john.r.strohm Re:No Stewart platform... (128 comments)

Not really.

It was proven decades ago that you didn't need a motion base under a flight simulator if your visual scene generator was good enough.

What is interesting is that the visual scene doesn't have to be all that good.

1 year,20 days

Man Builds Fully-Functional Boeing 737 Flight Simulator In His Son's Bedroom

john.r.strohm Re:Can't That Get You Marked as a Terrorist, Now? (128 comments)

There's no such thing as an "Airbus 757". Boeing builds the 7x7 airplanes. Airbus builds the A3xx birds.

I'm scheduled to take my first-ever Airbus ride in November (maybe sooner). I almost took one back in March, but Cathay Pacific put me on the earlier flight, which was on a 767.

I'm not really looking forward to it.

1 year,20 days

Man Builds Fully-Functional Boeing 737 Flight Simulator In His Son's Bedroom

john.r.strohm Re:Can't That Get You Marked as a Terrorist, Now? (128 comments)

It was a Boeing 777.

VERY good airplane. (Direct quote from an American Airlines 777 First Officer: "Sweetest-flying airplane I ever flew!" Direct quote from a very senior American Airlines 777 Captain: "10 years in 757/767. First time I got in the 777, I realized they'd fixed things I hadn't realized had been bugging me.")

1 year,20 days

The Aging of Our Nuclear Power Plants Is Not So Graceful

john.r.strohm Re:NIMBY (436 comments)

With all due respect, natural gas is generally far too valuable as a chemical process feedstock to burn for electricity or heat.

about a year ago

The Aging of Our Nuclear Power Plants Is Not So Graceful

john.r.strohm Re:NIMBY (436 comments)

Wind power, no matter where it is located, suffers from Carnot efficiency limits: the amount of power per unit "size" you can extract from a machine is limited by the temperature differential across the machine. This is fundamental physics, and will always mean that wind machines have to be physically HUGE for the amount of power they generate.

Compare a wind machine with a nuclear submarine powerplant.

For offshore wind, you also have the transmission line problem: you have to get the power from where it is generated (harvested) to where it is needed.

Geothermal: there aren't that many geothermal sites available, last I heard.

about a year ago

The Aging of Our Nuclear Power Plants Is Not So Graceful

john.r.strohm Re:NIMBY (436 comments)

Let me see if I understand this.

You're saying that, as we shift from reliable power sources (coal, nuclear) to unreliable ones (wind, solar), we should shift that unreliability penalty to the end user, who just has to live with the fact that his power is unreliable?

Where I come from, the system designer's first job is to ensure reliability: when the user throws that switch, the machine is supposed to work. Every time.

Seriously: In the name of energy efficiency, would you consider incorporating a random "Walk to work today" module into your car, such that, every so often, it would refuse to start? With no recourse whatsoever for emergencies? That is what you are proposing for unreliable energy.

about a year ago

The Aging of Our Nuclear Power Plants Is Not So Graceful

john.r.strohm Re:NIMBY (436 comments)

I invite you to observe that the quantity of nuclear waste per kilowatt-hour generated is very very small, compared to the quantity of carbon dioxide and other pollutants, including radioactives, emitted per kilowatt-hour by a coal-burning plant.

You COULD figure this out by noticing that a coal-fired plant takes many, many freight trains of coal per year to haul the fuel in, while a nuclear plant takes on semi-trailer I think every two years or so.

It is also worth noticing that the United States is the only country doing nuclear power generation that does not recycle (reprocess) the spent fuel rods, so that more energy may be extracted, leaving less total waste.

about a year ago

The Aging of Our Nuclear Power Plants Is Not So Graceful

john.r.strohm Re:NIMBY (436 comments)

With all due respect, you appear to fail to understand the distinction between base load plants and topping plants.

Base load plants supply the huge amount of power that MUST BE THERE 24x7. Topping plants supply the variable amount that is or is not needed depending on seasons, weather, uncharacteristic heat waves, sudden cold snaps, Pink Floyd concert light shows...

MOST of the power demand is base load demand. Heating and cooling don't stop. Water pumping doesn't stop. Hospitals run 24x7. Ditto traffic lights.

For topping plants, there are lots of choices, natural gas being a popular one. For base load plants, there are at the moment exactly three viable choices: hydroelectric, coal, and nuclear (to be precise, negative void coefficient pressurized water reactors). We are maxed out on hydroelectric power: every dammable river in the country has already been dammed. Coal is about the dirtiest power generation technology known to man, as well as one of the most dangerous (Google "black lung disease" someday). That leaves nuclear as Hobson's Choice, if you actually care about environmental and safety issues. (Hint: Of the three, only one emits significant quantities of carbon dioxide.) (For that matter, if coal plants were held to the radiation release limits applied to nuclear plants, it would be impossible to light up a coal plant, because of the radioisotopes in the coal (carbon-14 being the big one) that go straight up the smokestack and into the atmosphere.)

*ANY* base load plant costs a lot of money and takes a long time to build, because, by their very nature, they are BIG.

Finally, observe that wind and solar are utterly unsuitable for base load, because the wind doesn't always blow, and the sun effectively "goes out" for several hours every day.

about a year ago

U.S. District Judge: Forced Decryption of Hard Drives Violates Fifth Amendment

john.r.strohm Re:My goodness (417 comments)

I wish it was that good an answer.

I RTFA. It wasn't.

This was a hearing on a motion objecting to a procedural point. The previous proceeding, in front of a Federal magistrate (not a judge: key point, although obscure) at which the order to decrypt the drives was issued, was attended only by the prosecutors and the magistrate. Defense counsel was not present and was not able to argue against the order. According to TFA, the judge agreed with this part of the motion, set the order aside, and ordered both parties to submit additional briefs on the matter.

It isn't over.

At this point, as I read the tea leaves, even if he wins the 5th Amendment case, Feldman is toast. They found kiddie porn on the one piece they were able to crack. They also found financial data on the drive that ties it to Feldman. Even if the prosecutors are forced to go to trial with just what they have today, they almost certainly have enough to convict him for possession of kiddie porn and put him in prison.

about a year ago

Should the Power of Corporate Innovation Shift Away From Executives?

john.r.strohm Texas Instruments did this for years (149 comments)

I worked for Texas Instruments Defense Systems and Electronics Group from early 1988 through about mid-1999.

TI DSEG had LOTS of R&D money available, and MANY different internal programs for handing it out. The most important one was called IDEA (I don't know if it was an acronym or not, or what it may have stood for). IDEA was designed to hand out small chunks of first-round funding, enough to keep one engineer with a crazy idea that just might work fed and working for a couple of months, while he threw together a detailed study proposal, saying how to do a pilot project to see if there might be something to the idea. IDEA money was EASY to get, and there were multiple paths to it. If you for whatever reason didn't want to go through your management, that was no problem at all: *ANY* IDEA coordinator ANYWHERE IN THE COMPANY could listen to an IDEA pitch from ANYONE, and, if it sounded AT ALL plausible, throw some funding at him.

The whole idea behind IDEA was that most IDEA projects were EXPECTED to fail, but they'd generally fail quickly and cheaply. The ones that didn't fail got more funding, and more detailed investigation. Wash, rinse, and repeat, and every so often something REALLY good would pop up, that would make TI a huge chunk of money, enough to justify all those little failed efforts, and some not-so-little failures as well.

about a year ago

How Sequestration Will Affect Federal Research Agencies

john.r.strohm Re:Same old same old (277 comments)

From a David Casey online newsletter, courtesy of a friend's blog:

Lesson #1

US Tax revenue: $2,170,000,000,000
Federal budget: $3,820,000,000,000
New debt: $1,650,000,000,000
National debt: $14,271,000,000,000
Recent budget cuts: $38,500,000,000

Let’s now remove 8 zeros and pretend it’s a household budget:

* Annual family income: $21,700
* Money the family spent: $38,200
* New debt on the credit card: $16,500
* Outstanding balance on the credit card: $142,710
* Total budget cuts so far: $385

about a year ago

Missile Defense's Real Enemy: Math

john.r.strohm Re:Simply put... No. (589 comments)

There's something else about Iron Dome.

As long as the Bad Guys are throwing unguided rockets, they're basically just a nuisance.

The moment they start throwing guided missiles, they cease being a nuisance and graduate to being an actual threat. Israel historically has taken swift, decisive, and violent action against actual threats. (Recall the Six Days War.)

For all their rhetoric, Iran really doesn't want to get into a hot shooting war with Israel.

about a year and a half ago

Missile Defense's Real Enemy: Math

john.r.strohm Re:The problem with averages (589 comments)

However, the average person most certainly DOES need to understand Rolle's Theorem, since it is the theoretical underpinning of the Laffer Curve. (Laffer himself has observed that the curve bearing his name is a trivial application of Rolle's Theorem.)

Rolle's Theorem says that given a differentiable function f(x) and two points a and b such that f(a) = f(b) = 0, there exists at least one point c such that the derivative f''(c) = 0. To get the Laffer Curve, f(x) is tax revenue as a function of tax rate, a = 0% tax, and b = 100% tax. (Hint: It is generally safe to assume that nobody will work for free. Then somewhere between 0% tax and 100% tax there is a point beyond which tax revenue goes DOWN instead of up when tax rate is increased.

about a year and a half ago

Putting Biotech Threats In Context

john.r.strohm Re:Preston's Other Works - Related (117 comments)

To me, "The Cobra Event" reads and feels like it started out to be another nonfiction book, similar to "The Hot Zone". I got the distinct feeling that someone said something to the author that gave him the screaming willies and he decided it would be safer all around to make it look like fiction.

In the afterword, he points out that every item he described in the book was real, although some of them had different names.

about a year and a half ago

Elon Musk Offers Boeing SpaceX Batteries For the 787 Dreamliner

john.r.strohm Re:Batteries if you must (163 comments)

I wore a full beard for many years. I shaved it off several years ago, on medical advice (concern about allergens trapped in the beard possibly aggravating severe chronic bronchial asthma). It didn't help the asthma, but the informal poll of adult females of my acquaintance, who'd seen both versions, ran about 30-1 or 30-2 that I looked better without it.

I'm not completely stupid.

I initially kept the mustache, and that was OK with them. I shaved it off when the doctors cleared me to return to SCUBA diving and my mask wouldn't seal properly over it.

about a year and a half ago


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