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Comment Um, why do we need an IoT? (Score 3, Insightful) 46

Okay, an internet connected thermostat does add functionality. An internet connected fire detector and an internet connected home security system also makes sense. (Though if you're working on a home security system that hooks up to the Internet and you don't think about software security, you're an idiot who needs to be put into protective custody and fed by a nurse so you don't accidentally poke your eyes out while eating with a plastic fork.)

But why do I need an internet connected oven, refrigerator, or toaster? Do I need an internet connected coffee maker? An internet connected microwave? What value do they add, really? Notifications?

Comment Time is also a cost (Score 1) 654

Time is also a cost; if it takes me 20 minutes to drive somewhere by car but an hour to get there by mass transit, then the equation makes no sense. If, on the other hand, you live somewhere where driving is impractical and an hour drive can be replaced by 20 minutes on mass transit, then clearly I'd take mass transit almost regardless of the cost.

Comment Conduits everywhere. (Score 2) 557

Make sure that they run whatever cable you decide to run (ethernet, fiber, whatever) in conduit, ideally with junction boxes on a relatively regular basis (at bends, etc), so it is easy to draw new wire through when you need to.

Yes, the electrician will say "you don't need to do that; that's silly." Ignore him. Do it.

I just recently moved into a house with ethernet run through to all of the rooms from an access point in the basement. Unfortunately over the years some of the runs have deteriorated--but sadly, the ethernet wire was simply threaded through holes in the studs, making it virtually impossible to pull new wire through. Had it been drawn through relatively large conduit, and had there been boxes on a regular basis, it would take just a few minutes to draw a new wire.

That also goes for conduits where you may want to put a big screen TV on the wall, low voltage systems (like door bells), and other runs where you may want to add something new (like in-home speakers or whatever). I know it's impossible to plan for everything, but at least you'll have a fighting chance when some new technology comes around (or something in the wall breaks), that it can be easily replaced without having to tear up a whole lot of drywall.

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

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

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

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

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.

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