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Comment: Re: just put a motor on the elevator itself (Score 1) 235

by dj245 (#48924397) Attached to: Engineers Develop 'Ultrarope' For World's Highest Elevator

No, you could use a conductive rail, like a subway, and rack and pinion system to move the elevator. The rack and rail would add a fair bit more total weight to the building compared to a cable. But more importantly, the motors would have to be much much more powerful! Modern elevator systems have a counter-weight balanced on the other side of that cable, which means the motor only has to overcome friction and the small difference in weight between the elevator and counterweight (which varies depending on current payload). The motor on an elevator like Noah is suggesting would have to provide enough force to counteract the entire weight of the elevator + payload + motor + friction, which is at least an order of magnitude more than a traditional elevator.

Let's not forget that rack and pinion elevator cars are significantly noisier, slower, and have much more vibration compared to traditional cable or hydraulic elevators. Rack and pinion is great for portable elevators but a poor choice for a short building, and an awful choice for a tall building.

Comment: Re:just put a motor on the elevator itself (Score 1) 235

by dj245 (#48924367) Attached to: Engineers Develop 'Ultrarope' For World's Highest Elevator

i would do away with the motor at the top of the shaft, and instead electrify each individual elevator so it has motive power. seems like the best solution to me.

The only benefit to doing this is to eliminate the cable. That leaves you with rack and pinion drive as basically the only realistic* option for moving the car up and down. Rack and pinion elevator cars are slower, noisier, and have substantially more vibration than hydraulic or cable elevator cars.

*Another option is a pneumatic elevator, but those are even slower and less suited for tall buildings.

Comment: Re:Who eats doughnuts with the doughnut men? (Score 2) 450

by dj245 (#48915275) Attached to: Police Organization Wants Cop-Spotting Dropped From Waze App

I dunno how it is in america (or any other country for that matter) but where i live, speedometers in cars are required by law to over-report speeds by a small percentage.

I don't think the USA has such rules. The issue is most likely because the speedometer measures tire rotation with an assumed tire diameter. New tires will indicate close to the true speed, but as the tire wears down, it has to rotate more to travel the same difference, and therefore the reported speed will be higher than true speed.

Car manufacturers would get a lot of complaints if their speedometers were underreporting the speed, so they probably add a little margin to ensure that doesn't happen.

Comment: Re:Saddest line ever (Score 1) 140

by dj245 (#48914865) Attached to: Young Cubans Set Up Mini-Internet

When every article about a communist, pseudo-communist, or crypto-communist country has to have a post like this (and it's in every thread), it's time to start thinking about why and how all communist countries (save, perhaps, India) become totalitarian hell-holes, and whether communism as a pure ideology is too hopelessly broken to implement in reality. Not to mention that it seems to me that no Scottish communism on earth is True Scottish communism.

Western democracies are heading in that direction, but so far every country with a communist economic model has to start there.

Democracy (at least how the US practices it) have problems too. Just as 1 example, we have no mechanism for long-term planning with any teeth to "stick to the plan". When we pass budgets other laws/plans for the 5-10 year future, we have to put in "poison pills" or use other tricks to make them harder to reneg on. But that doesn't matter either because the politicians just repeal the poison pill part of the law the second it benefits their career.

Comment: Re:Money *needs* to be removed from Politics ... (Score 1) 178

We chastise China, Cuba, N. Korea etc. for not having democracies, but neither do we

Yes we do. Democracy doesn't mean we get the government we want, just the government we voted for. The people in congress were elected in free and fair elections.

I know, technically we were a "republic", not a "democracy"

I don't know where this idiotic meme, that a "republic is not a democracy" started, but repeating it doesn't make you look intelligent, it makes you look stupid. Please stop doing it.

I think part of the US's political problems is that there is absolutely no mechanism for long-term planning. Places like China (through its ironhanded 1-party system) and Saudi Arabia (through a monarchy) can make long-term plans and stick to them unless the situation changes. 5-year and 10-year programs are a lot more common in non-democracies. The US doesn't have any mechanism for this, so our governing is just reacting to problems and kicking the can down the road. Even if both parties agree to a plan which lasts longer than a year, they are free to (and almost always) change it just as soon as it is convenient or beneficial for their career to do so.

I think the US would benefit a lot if we had an additional branch of government which set broad long-term goals for the benefit of the country, and had sufficient power to make it happen. Checks and balances would need to be added. Companies which only look to the next quarter struggle in the long run, and Countries are no different.

Comment: Re:Technical limitations (Score 1) 254

by dj245 (#48906165) Attached to: Verizon, Cable Lobby Oppose Spec-Bump For Broadband Definition

There are some technical reasons that the telecom monopoly lobbying groups REALLY don't want broadband to be defined at high speeds. It rules out a wide range of very cheap technologies which can be used to claim that they do provide broadband. At 25/3 you need to offer at least ADSL2+M (ADSL2 won't cut it), DOCSIS systems will be severely limited in the number of subscribers, GPRS is out (you need to move to HSPA) and so on. Setting a very low limit for what is broadband is a perfect way to polish the numbers and make it look like good service is provided at very reasonable prices. We have sold refurbished telecommunication equipment to the US, which was no longer considered competitive in the northern European market, but was state of the art for many parts of the US.

While it is certainly nice to have a place to unload old equipment I don't think it is in the best interest of the USA to play catch up on infrastructure just to help a few telcom companies to keep their profit margins high...

That raises the question- Where are the large router and telecom equipment manufacturers on this issue? Don't they have lobbyists too?

Comment: Re:Jesus, we're fucked. (Score 1) 351

by Teancum (#48901547) Attached to: Americans Support Mandatory Labeling of Food That Contains DNA

As she continued to ignore me my explanations grew longer and more detailed, until finally she interrupted me with "What's inertia?"

After you explained the concept, did she at least understand the idea but not the term, or was even the concept of inertia something that was a revelation?

Comment: Re:Discussion is outdated (Score 2) 484

by Teancum (#48901397) Attached to: Ask Slashdot: Is Pascal Underrated?

I *think* that fpc Pascal can not properly handle utf8 strings

Only because of purists that insist a six byte character is counted as one character.

A lack of documentation is an issue, but that is simply because it is an open source project. About par for the course on most open source projects, from my experience too. Delphi has some amazing documentation, but then again they can pay for that documentation to be developed.

Comment: Re:Modula-3 FTW! (Score 1) 484

by Teancum (#48901381) Attached to: Ask Slashdot: Is Pascal Underrated?

People gave up on Pascal and moved to C++ back then for a reason.

It wasn't really for a good reason other than simply the choice of the software development shop, as well as the cost of compilers where C compilers were widely used as assignments in Computer Science graduate courses... thus frequently offered for free. Arguably a C compiler is also easier to write than a good Pascal compiler, so it frequently is the first compiler available for a given instruction set or computer architecture.

That doesn't mean it is necessarily inferior or for that matter better than C++ for high level application development. It does explain why you see fewer people developing in Object Pascal vs. C++.

Comment: Re:Modula-3 FTW! (Score 3, Interesting) 484

by Teancum (#48901253) Attached to: Ask Slashdot: Is Pascal Underrated?

Wow, I hope you're not suggesting 22 div 3 vs. 22/3 is more intuitive to a novice for what it does compared to 22/3 and 22/3.0!

A properly designed compiler (like Turbo Pascal and later Delphi) makes no distinction nor software penalty for using either convention. This is nit picking at such a minor detail, although as a software developer I like to emphasize that I am using an integer division as opposed to floating point, thus deliberately use the div operator when appropriate. For a novice, it shouldn't make any difference at all.... particularly for the kinds of applications developed by a typical novice that would have any sort of confusion over this issue (or some C++ developer tasked to do some Object Pascal debugging).

Comment: Re:Modula-3 FTW! (Score 3, Informative) 484

by Teancum (#48901197) Attached to: Ask Slashdot: Is Pascal Underrated?

From a maintainability standpoint when you need to have code written by an experienced software developer familiar with Pascal and its various (current) compilers as opposed to an experienced software developer familiar with C++... when you hand those software packages over to another developer to continue development by somebody having to start cold on that software and fix bugs, make extension, or overhaul that code... I dare say that the software written in Object Pascal can be developed sooner than a comparable application in C++. My direct experience has been in about half of the time or less than a comparable C++ program.

That is my standard for readability. The only reason you might notice some developers who have a hard time with Pascal readability is mainly due to the fact that the developer is simply unfamiliar with Pascal syntax due to a lack of development in that language for a prolonged period of time. Handing Object Pascal code to somebody else already familiar with the language clearly has a huge advantage.

Just because it is different doesn't mean it is worse. It might mean that you would need to personally take some extra time to learn another programming language. Besides, for a Pascal programmer, curly braces are for comments and stand out very well for that purpose.

Comment: Re:Other than the obligatory security theatre... (Score 1) 110

by dj245 (#48898353) Attached to: Bomb Threats Via Twitter Partly Shut Down Atlanta's Hartsfield Airport

And to give the elyappearance of "doing something" in a situation where realistically, nothing can be done. It is very important for governments to always give the appearance to be in control and that they know what they are doing, even when any halfway smart person knows neither is true most of the time.

If the bomb was a time bomb. If it happened to be triggered remotely, why not bring assets into play that might be able to block such signals? Since we don't know the bomb characteristics, or even if these is a bomb, it is a safe move to play. And fighter jets can almost certainly get on station quicker than an AWAC type plame.

Comment: Re:Bullshit (Score 5, Interesting) 210

by dj245 (#48890897) Attached to: At Oxford, a Battery That's Lasted 175 Years -- So Far

From The Fucking Article

"You'd think it'd be annoying as hell for a bell to be going off, constantly, for 175 years—but the voltage left in the battery is so low that the human ear can't actually hear the ringing. Instead, the clapper oscillates back and forth between the bell constantly, which you can see happening in this video. At this point, the experiment is more of a curiosity than anything—Croft says that the battery pulls 1 nanoAmp each time it oscillates between the bell’s sides, which is an exceedingly low amount of energy."

1 nanoamp is so tiny that it may be being recharged from the environment somehow.

"The pyramid is opening!" "Which one?" "The one with the ever-widening hole in it!" -- The Firesign Theatre

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