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Comment: Let's close it because it's too popular. Really?!? (Score 2) 203

by w3woody (#49653487) Attached to: Critics Say It's Time To Close La Guardia Airport

According to AirNav, La Guardia handles around 1013 aircraft operations a day; that's 1013 takeoffs and landings per day. Compare to JFK, which handles 1232 aircraft operations a day with twice as many runways, or Newark, with 1098 aircraft operations a day.

The airport might suck and may or may not be inconvenient, but it is handling far more traffic than can be diverted to another existing airport. You could expand another existing airport to handle the excess traffic--but where? Teterboro? Caldwell in Essex County? Long Island Mac Arthur?

And the entire industry is moving away from long haul flights to shorter regional hops, meaning traffic operations are only going to increase. So assuming you can just divert all the flights to JFK and Newark isn't going to work; split the number of flights between the two and now you have two airports handling about the same amount of traffic as LAX, with 1741 flights/day. So even if we assume those airports can handle the increase in traffic, that pretty much will max out both airports and prevent future expansion.

Hong Kong International took nearly a decade to construct, in a regulatory environment which makes it easy to steamroll in large infrastructure projects. So constructing a new airport near Rikers Island is not going to happen over a weekend.

And if you did go the Hong Kong route, you may be better off spending the money, moving everything off Rikers Island, and expanding the airport by paving Rikers and adding two additional runways, modernizing La Guardia, and extending the subway system to run out to the terminals there.

Comment: Re:"water, making landing difficult and hazardous" (Score 1) 203

by w3woody (#49653397) Attached to: Critics Say It's Time To Close La Guardia Airport
That was pilot error caused by a pilot who failed to keep the proper speed on approach to an airport where the ILS glide slope was out of service. That could have happened at any airport. Fortunately it did not happen at an airport where there were tall buildings along the flight path, otherwise the damage would have been far worse.

Comment: Re:A first step (Score 4, Interesting) 299

by w3woody (#49550439) Attached to: Tesla To Announce Battery-Based Energy Storage For Homes

Mine's more.

Where we moved to in North Carolina, we're only served by two utilities: AT&T (for internet/phone/TV) and Duke Progressive (for electricity). We use electric heating--which is expensive, and while our neighborhood will be getting natural gas in the next few months, it makes no economic sense for us to replace our central heating system with gas. (The payoff exceeds the lifespan of the HVAC already installed.)

I have to admit, the primary reason for not getting solar where we've lived in Los Angeles and now in Raleigh is that it didn't make a lot of economic sense. But as solar cell prices drop, having a battery-backed solar system on my house starts to sound more promising--especially after the last storm which knocked out our power for a couple of days.

Since we are on a well and septic tank, if we can get most of our power from solar then we can pretty much be self-sufficient if there is a major disruption in the future--and that's worth a premium over what we now pay for electric service.

Comment: Re:Check their work or check the summary? (Score 1) 486

by w3woody (#49336491) Attached to: No, It's Not Always Quicker To Do Things In Memory

Really, what's happening is that they're performing repeated concatenations of various length strings--an operation that eventually becomes O(m*n) time, with m being the length of the string and n being the number of strings. (Concatenating strings in Java requires a new string to be created, then the contents of the two source strings copied into the new destination.) Appending a file, on the other hand, is only an O(n) operation, but has a very large constant time associated with it. So, in essence: TL;DR: O(n**2) operations can be slower in memory than O(n) operations on disk for large values of n.

The real lesson is that you should understand what's going on underneath the hood. And in this case, if you're doing a lot of string concatenation operations in Java, you probably should be using the StringBuilder class. I mean, after all, that's why there are multiple ways to do the same thing in Java (like ArrayList verses LinkedList): each offers different performance characteristics, and at the fringes performance characteristics can kill your application.

Comment: Re:Not a watch (Score 1) 111

Rolex, in fact, hand-manufactures its own movements. Some processes of the manufacturing process do use some degree of automation, and of course a number of jigs are used during the assembly process. But they are hand-built movements built internally by Rolex.

The reason why people think Rolex outsources their movements is because Rolex doesn't talk much about their movements, and because Rolex used to use Zenith watch movements in some of their watches, such as the Daytona. (Since 2000, the Daytona has used an in-house movement--and I suspect this move to bring all their movements in-house is what drove Zenith to release their own complete watches.)

Omegas, on the other hand, mostly uses mass-manufactured ETA movements rather than using movements made in-house. While ETA movements are certainly of a much higher quality than mass-manufactured movements from China, they are still basically mass-produced watch movements.

Comment: Re:Not a watch (Score 3, Insightful) 111

Try "thousands", if the movement is built in-house and has more than a couple of complications. Ah, hell; try hundreds of thousands for a custom watch movement with more than a handful of complications--mostly due to engineering costs of designing the movement, which can take years. And when you get to the extreme high end of the watch movement market, they start becoming small analog computers, such as this Patek Philippe pocket watch, which has a complication which calculates the sidereal day, and was constructed in 1933. Or this Jaeger-LeCoultre, which consists of over 1400 individual parts and 26 separate complications.

Comment: Yeah, this will go as well as a lead balloon. (Score 2, Insightful) 111

I own a Rolex DateJust in Gold and Stainless Steel, and someday I'd like to own a Jaeger-LeCoultre Master Ultra Thin Moon 39 in Stainless Steel, as well as a Breitling Navitimer 01. For my father's 70th birthday we bought him a Navitimer 01, which he just loves. (My father and I are both private pilots.)

Here's the thing about luxury watches: for women, you can wear necklaces, wrist bands, rings and earrings. But for men, the only pieces of jewelry that a man can wear (and get away with it) is cufflinks, a tie clip and a luxury watch. And if you're not wearing a shirt with french cuffs, or wearing a tie, then all that is left is the watch.

So basically a luxury watch is jewelry. Functional jewelry, but jewelry all the same. And like all jewelry, if its taken care of you can inherit it from your grandparents (as my wife inherited some pieces), you can receive it when you are young and still wear it when you're old, and you can pass it down to your grandchildren.

When you start looking at luxury watches, you find there are two types: those which use an in-house built movement built by craftsmen who sweat the details and who create all sorts of intricate complications which do interesting things (like keep accurate time, provide a stopwatch function, show the phase of the moon, the day of the month, the month of the year), and those who buy an off-the-shelf movement and wrap it in gaudy jewelry.

From what I've read (I'm not a collector but I'd like to be one someday if I ever really strike it extremely rich, because mechanical wrist watches fascinate me no end), watches from watchmakers who build their own movements are highly respected. Watches from watchmakers who buy their movements from third parties, however, are not very well respected. And the worst are those who use quartz movements: essentially an electric powered watch movement regulated by a small oscillator crystal. Like about 1/3rd of Tag Heuer's product line, many running up into the 10's of thousands, which horticulturally have more in common with a cheap Casio than with an A. Lang & Sohne.

This is why I think luxury smart watches will be an unmitigated disaster. Sure, some people will buy them--because some people have more money than God, and to be able to show off a $10,000 smart watch that you're just going to toss away in a couple of years when the electronics are out of date would be the height of "one upping the Joneses." But I cannot see them being any more interesting to someone fascinated by mechanical watches than a quartz Tag Heuer--it's the sort of watch someone with no sense of connection to the past or any sense of connection to the tradition of hand-crafted watches would shove in your face to exclaim how much better they are than you.

You know: crass assholes.

Comment: Re:It's almost like the Concord verses the 747 aga (Score 1) 157

by w3woody (#49154569) Attached to: Hyperloop Testing Starts Next Year

I just cannot see how a large tube holding a vacuum extending 100 miles or 300 miles or 500 miles or 2,800 miles is ever going to be cheaper than a rail track the same length (assuming right of way problems can be solved--and note the high speed rail system between SF and LA had to be slowed down because right-of-way issues put too many curves in the track) is ever going to be cheaper per passenger mile. And if it turned out per passenger mile a train was cheaper (without government subsidies) than flying a fleet of 737's, do you think investors in their right mind would fly a fleet of expensive 737's when they could run cheaper trains?

And one thing people forget when counting the cost of using trains to transport people or goods is the fact that the first railroads which connected the U.S. continent was built on the cheap with slave labor.

Comment: It's almost like the Concord verses the 747 again. (Score 5, Insightful) 157

by w3woody (#49153497) Attached to: Hyperloop Testing Starts Next Year

Meaning the Boeing 747 became extremely popular while the Concord wound up eventually going to the dustbin of history because per passenger-mile, the Boeing 747 was cheaper than the Concord, despite taking much longer to move passengers from New York to London.

And that's the problem I see with the Hyperloop: sure, it may be technically possible to send passengers in a train in a tube with a vacuum at 800 miles per hour from Los Angeles to New York, but at the end of the day, its the cost per passenger mile that matters. And a large airplane traveling along at 500 miles per hour, which doesn't require 3,000 miles of dedicated hardware to travel through, is going to be far cheaper than buying a 3,000 mile strip of land and building a tube. across it.

Comment: Re:Sounds good (Score 5, Interesting) 599

by w3woody (#49126339) Attached to: Republicans Back Down, FCC To Enforce Net Neutrality Rules

I'm also concerned partially because at its root, the problem with broadband in this country is a lack of local choice. I believe competition (such as Google Fiber) going up against the phone company and the cable company would help lower prices while raising speeds far better than regulation that explicitly acknowledges monopoly status and exchanges (easily watered down) performance demands for guaranteed profit margins on (easily manipulable) books. I mean, the real problem with explicit acknowledgement of monopoly status is an implicit guarantee that the phone company and the cable company may not fail--and if they make poor infrastructure investment choices, they're insulated from failure.

I'm not suggesting this can't work. Only that there are a bunch of ways in which this can go haywire, so to me, the FCC's actions is simply the first step in a very long battle.

Comment: Interviews and candidate quality. (Score 1) 809

by w3woody (#49049607) Attached to: Ask Slashdot: What Portion of Developers Are Bad At What They Do?

I've both helped hire people and have been a hiring manager, as well as the hot-shot programmer and now becoming the wise gray-beard everyone speaks reverently to and then ignores.

When I interview a candidate on the phone, my primary interest is to screen out the candidates who are either obviously lying on their resume, or who have inflated their resume or are otherwise uncommunicative. (You'd be amazed at how many are unable to hold a conversation about the stuff they've supposedly worked on for a couple of years. Almost as if they put it into their resume just to inflate it. And I feel free to go through any part in the resume; for example, I dinged a guy because he put in his resume he was a private pilot. Having a father who was a pilot and learning to be a pilot myself, I asked him questions related to his being a private pilot--which he utterly failed to answer. And if you're willing to lie about something that irrelevant, what else are you lying about?)

In person, however, I may ask a couple of questions about the specific work I'm doing. But for the most part I stick to straight forward development questions: I ask the person to solve a problem which requires a loop, to walk a linked list, to search for primes. What I'm looking for, however, isn't if the person is a mathematician, but how he solves the problem: does he automatically close the curly brace when he writes the open curly brace at the top? Does he store intermediate results somewhere, and how does he chooses to store them? Does he use any naming conventions in his sketched out code? When he gets stumped, how does he talk to me about solving the problem? Does he come up with anything I hadn't thought of?

And that's because I'd rather hire someone who seems smart and communicative and who can sketch code on the fly than someone who may happen to know about public/private key systems.

My theory is that specific problems that revolve around the web site can be learned on the fly: someone who is smart can look up how OpenSSL works, for example, and start implementing code against OpenSSL. But someone who has OpenSSL experience but who is otherwise unable to communicate effectively or solve problems on the fly is going to be useless as soon as we move on to other problems.

And my theory is the same regardless if you're hiring a beginner out of college or an architect with 20 years of experience; the architect I'll just ask much harder questions, as well as probative questions about the sort of design work he's done and the types of design problems he's had to face.

In terms of quality, I've found that roughly a quarter of the people I interview I'd happily work with, but for architectural level stuff, it's hard to find someone who is really good. That's because software development seems to weed people out after 10 to 20 years--and many who survive that long do so out of inertia, not because they're really good at what they do. So if you want someone with 20 years of experience who can architect something complex and get it right the first time--you're going to be looking a long time.

(And if you happen to be hiring in Raleigh, North Carolina and are paying above competitive rates for a first rate architect and developer, send me a private message. :-D )

MATH AND ALCOHOL DON'T MIX! Please, don't drink and derive. Mathematicians Against Drunk Deriving