also: catamarans are "not stable for the same reason that square hulls are". that statement alone shows a basic misunderstanding of boat design and simple physics/statics.
a catamaran is stable because if you imagine one side unsupported (such as a wave dropping out frm under it) you have a CG which extended beyond the vessels "base", ie, the remaining outrigger. this causing a natural tipping moment until the unsupported outrigger comes into contact with teh water again.
you're only correct if youre talking about a hull riding smack on the surface and not extending beneath it. ie, you're ignoring CG, displacement, and actual bouyancy dynamics and vastly oversimplifying the problem.
the bouyancy forces acting on a hull dont care if they are acting on the angled side of a V hull or the flat bottom of...well a flat bottomed boat.
the surface area of the horizontal plane of the boat hull where it intersects the waterline is effectively a "flat hull", or the "area upon which the bouyancy forces act", for any boat, regardless of whether the hull is a perfect square or a perfect circle or inverted triangle.
two hulls with different shapes but the same surface area of that plane (and the same displacement and CG are equivealent) will have the same bouyancy forces acting upwards on the hull.
Humanities is religion for people who don't believe in a deity.
No, that's science. All work and no play makes Jack a dull boy.
Likewise, all science all the time teaches you lots of facts and figures...but nothing of human nature, social interaction, history (lest ye be doomed to repeat it), etc. The humanities are important. Art, literature, etc, these are what actually make up a culture. A civilization so devoted to science and math that they ignore all else will have no beauty, no individuality....essentially the Borg, or Observers, or whatever scifi junket you choose. Point is: you (if not you personally, then at least society) need the humanities. And frankly, someone who is well rounded and has taken a few humanities will be far mroe interesting than someone who hasnt.
(and for the record, im a very facts and logic driven person who hated taking literature and art...it was only after several years that I learned what I had missed out on by doing bare minimum, and retook courses in them)
no what need is to use it to figure out the route between what i say and my wife's interpretation centers, and back again, so i can figure out how mad she'll be and why about whatever normal innocent thing i say before i say it, and i can properly interpret it when she says "Fine" or "Really?".
(really really need an edit button) although...one reason jets are hot is because its a consequence both of the required pressures need to both keep the reaction self sustaining and not escaping out the front (essentially a pressure wall from the compresor stage so it can only go rearward), and combustion itself. the heat itself isnt necesarily required, it's "just there". so if they could get the required pressures and airflow for their power turbines to work without as a much heat, so much the better for them i guess.
i can explain the mechanics of the engine, but the physics/thermodynamics of the heat and flow etc is not something im expert on so i actually cant really speak to how they could get it working at 100C, though i do recognize that its unusually "cool". i guess it would just depend on how much energy they need to drive the rotors themselves, and i'd just be guessing.
mechanically, it did seem odd that the power turbines are seemingly integral to the rotor mast/housing, no reduction gearbox. as for getting rid of it (the air), i wondered if they were maybe bleeding the air into the blades and out the tips once it was used.
when i say "some helicopter have a direct link" its referring more to much older designs using piston engines. i dont know of any turboshaft powered helos that have a directly linked xmission....since as stated thats wher ethe name of the powerplant type comes from! so..there.
This is actually not new technology. In fact, most turboshaft helicopters already use this sort of system, eg: Hueys and Cobras (my background)
What you have here is a non-physical or indirect link between the engine and rotor transmission. In some helicopters the link is direct or physical. IE, the transmission gearbox is directly attached to the engines output shaft, just like a car with a direct connection. This means the transmission must input must therefore spin at the same RPM as the engines output.
What they have done is the helicopter equivalent of the torque converter in your car. The rotor transmiion and gearbox is NOT directly connected to the engine's output shaft.
So how this works is you have a turbine engine. A jet engine basically. It produces a jet exhaust. What Hueys and Cobras, and Im sure some other types as well, what they do is rather than put the xmission gearbox directly on the engines output shaft is they isntead have a seperate unconnected turbine in the exhaust stream. Thus, the hot, compressed and fast flowing exhaust turns this second turbine. And it's this 2nd turbine that is connected to the xmission gearbox and thus to the rotor. This is essentially like the torque converter now common in cars.
By not having a direct link you do reduce mechanical complexity, as well as increase reliability. The 2nd turbine, the one driven the by the exhaust, can be keyed differently, thuis naturally resulting in a lower RPM than the engines axial shaft, and without using a gearbox in between to step down the RPM. Thats where the reduced complexity and higher reliability come from.
In the case of Hueys/cobras we're talking about stepping down from a jet turbine (say, 40k RPM) to a Rotor speed of say ~120 RPM. That kind of gearboxing is going to have high streess, high wear and tear, be extremely hot, and need careful babying. So instead we put this power turbine in the exhaust stream and design it so it naturally spins at a slower speed for a given flow rate, achieving the same effect as a gearbox. Now this is obviously still going to be a higher RPM than the final Rotor output, so theres still gearboxing and further reduction (say ~2k to 120 rpm). But the big jump from the engines axial RPM is accomplished via exhaust air flow.
In the helo community the engine is thus commonly known as the "Gas producer" (Ng, rpm of the gas producer). So what they've done here is replace the jet engine as the gas producer with an air compressor, to achieve the same goal: air to drive a Power Turbine that actualy moves the rotor.
Also note, for space sake the two turbine shafts, engine and power, are usually coaxial, hence the name: turboshaft. Compared to jet engine with a propellor directly attached via gearing, which is the turboprop. (lot of words, but now you know a whole lot more about modern helo engines)
a lot of things are a win over the macbook air. i'm still waiting for the proper aspect ratio to come back. this one is still that horrendous widescreen ration intended for movies and not work.
but if we can learnt o understand hers, we can learn to understand others. eventually a methodology to map and understand the brain in a living person, without surgery, could be the norm. alzheimers beings to set in? No problem. Step into the BRI machine for a few a hours, doc reads the results, then they apply a small implant to the precise relevant location of your unique brain to repair the malfunctioning communication relay.
Wrong about this topic too. Man you just can't catch a break.
Few or no "regular" mass market car needs more than regular gas. Some luxury or performance cars, with a high performance engine with high compression ratios, will run more efficiently with it, but even then its not required because of the anti-knock sensors that are standard and have been for a while now. you lose a little performance, but they adjust the timing.
Read the manual. If it says the words "premium required" then fine, you might actually need it. If says "recommended" or nothing at all, and this is the overwhelming majority of vehicles, then premium is a waste of $$.
also humourous of course is that the Mayor just issued some boilerplate response in defense of the council, not even aware the the gent is a (volunteer) member of that very same council.
It seems that the alternative journalist he ticked off is a volunteer member of hte same Council that he is a volunteer member of. She wrote some inflammatory things about his wife's charity group (dealing with special needs kids), he got ticked, said some things, and the journalist in turn threatened blackmail of the "stop saying bad things about me, or we'll stop covering your wife's charity in the press at all". he of course didnt take that lying down and criticized the hournalist more......and so now the journalist, in the name of hte council that they are both volunteer members of, contacted a lawyer and had the C&D sent.
So in the end the C&D Lawyer is a middleman in their dispute. Now, he sent a very poorly written C&D and deserves all ridicule he has recieved on that (and failed in his own due diligence if he can so easily be trumped by such simple things as facts, as the shown in the response letter). but he was also just being used a pawn in the battle between the two individuals.
you're not bursting anyone's bubble let alone mine. i have considerable experience in aviation maintenance, primarily military, to back me up. even parts for new aircraft, for new civilian light aircraft, have a robustness to them you wont ever find in consumer electronics. its not merely a matter of being hard to get certified due to red tape clogging innovation.
Slashdot Mirror
mod up
That's exactly what it is. He knows nothing about boats of the physics behind them.
"Only stable because of the sail (which has ballast in it). "
seriously wtf. cant believe i missed this. sails dont have ballast.
you know nothing about boats Jon Snow
also: catamarans are "not stable for the same reason that square hulls are". that statement alone shows a basic misunderstanding of boat design and simple physics/statics.
a catamaran is stable because if you imagine one side unsupported (such as a wave dropping out frm under it) you have a CG which extended beyond the vessels "base", ie, the remaining outrigger. this causing a natural tipping moment until the unsupported outrigger comes into contact with teh water again.
you're only correct if youre talking about a hull riding smack on the surface and not extending beneath it. ie, you're ignoring CG, displacement, and actual bouyancy dynamics and vastly oversimplifying the problem.
the bouyancy forces acting on a hull dont care if they are acting on the angled side of a V hull or the flat bottom of...well a flat bottomed boat.
the surface area of the horizontal plane of the boat hull where it intersects the waterline is effectively a "flat hull", or the "area upon which the bouyancy forces act", for any boat, regardless of whether the hull is a perfect square or a perfect circle or inverted triangle.
two hulls with different shapes but the same surface area of that plane (and the same displacement and CG are equivealent) will have the same bouyancy forces acting upwards on the hull.
Yes, because no sailor ever thought of that, ever, in the 8000 years of boat design history.
Here you go AC. Educate thyself: http://en.wikipedia.org/wiki/Sea_anchor
to question everything....as long as its not:
evolution
big bang
climate change
(the best part of this pot stirring is that when the flames begin and call me stupid for questioning them, they make my point for me!)
Humanities is religion for people who don't believe in a deity.
No, that's science.
All work and no play makes Jack a dull boy.
Likewise, all science all the time teaches you lots of facts and figures...but nothing of human nature, social interaction, history (lest ye be doomed to repeat it), etc. The humanities are important. Art, literature, etc, these are what actually make up a culture. A civilization so devoted to science and math that they ignore all else will have no beauty, no individuality....essentially the Borg, or Observers, or whatever scifi junket you choose. Point is: you (if not you personally, then at least society) need the humanities. And frankly, someone who is well rounded and has taken a few humanities will be far mroe interesting than someone who hasnt.
(and for the record, im a very facts and logic driven person who hated taking literature and art...it was only after several years that I learned what I had missed out on by doing bare minimum, and retook courses in them)
Now I imagine the same joker that moded the GP "Funny" will also modteroll my post, because all things MS are automatically toxic to /., but:
the eternally security paranoid government uses IE.
no what need is to use it to figure out the route between what i say and my wife's interpretation centers, and back again, so i can figure out how mad she'll be and why about whatever normal innocent thing i say before i say it, and i can properly interpret it when she says "Fine" or "Really?".
(really really need an edit button)
although...one reason jets are hot is because its a consequence both of the required pressures need to both keep the reaction self sustaining and not escaping out the front (essentially a pressure wall from the compresor stage so it can only go rearward), and combustion itself. the heat itself isnt necesarily required, it's "just there". so if they could get the required pressures and airflow for their power turbines to work without as a much heat, so much the better for them i guess.
i can explain the mechanics of the engine, but the physics/thermodynamics of the heat and flow etc is not something im expert on so i actually cant really speak to how they could get it working at 100C, though i do recognize that its unusually "cool". i guess it would just depend on how much energy they need to drive the rotors themselves, and i'd just be guessing.
mechanically, it did seem odd that the power turbines are seemingly integral to the rotor mast/housing, no reduction gearbox. as for getting rid of it (the air), i wondered if they were maybe bleeding the air into the blades and out the tips once it was used.
damn we need an edit button. "and im sure some other types as well"...dont know why i typed that. damn stream of thought typing.
when i say "some helicopter have a direct link" its referring more to much older designs using piston engines.
i dont know of any turboshaft powered helos that have a directly linked xmission....since as stated thats wher ethe name of the powerplant type comes from!
so..there.
This is actually not new technology.
In fact, most turboshaft helicopters already use this sort of system, eg: Hueys and Cobras (my background)
What you have here is a non-physical or indirect link between the engine and rotor transmission.
In some helicopters the link is direct or physical. IE, the transmission gearbox is directly attached to the engines output shaft, just like a car with a direct connection. This means the transmission must input must therefore spin at the same RPM as the engines output.
What they have done is the helicopter equivalent of the torque converter in your car. The rotor transmiion and gearbox is NOT directly connected to the engine's output shaft.
So how this works is you have a turbine engine. A jet engine basically. It produces a jet exhaust. What Hueys and Cobras, and Im sure some other types as well, what they do is rather than put the xmission gearbox directly on the engines output shaft is they isntead have a seperate unconnected turbine in the exhaust stream. Thus, the hot, compressed and fast flowing exhaust turns this second turbine. And it's this 2nd turbine that is connected to the xmission gearbox and thus to the rotor. This is essentially like the torque converter now common in cars.
By not having a direct link you do reduce mechanical complexity, as well as increase reliability. The 2nd turbine, the one driven the by the exhaust, can be keyed differently, thuis naturally resulting in a lower RPM than the engines axial shaft, and without using a gearbox in between to step down the RPM. Thats where the reduced complexity and higher reliability come from.
In the case of Hueys/cobras we're talking about stepping down from a jet turbine (say, 40k RPM) to a Rotor speed of say ~120 RPM. That kind of gearboxing is going to have high streess, high wear and tear, be extremely hot, and need careful babying. So instead we put this power turbine in the exhaust stream and design it so it naturally spins at a slower speed for a given flow rate, achieving the same effect as a gearbox. Now this is obviously still going to be a higher RPM than the final Rotor output, so theres still gearboxing and further reduction (say ~2k to 120 rpm). But the big jump from the engines axial RPM is accomplished via exhaust air flow.
In the helo community the engine is thus commonly known as the "Gas producer" (Ng, rpm of the gas producer). So what they've done here is replace the jet engine as the gas producer with an air compressor, to achieve the same goal: air to drive a Power Turbine that actualy moves the rotor.
Also note, for space sake the two turbine shafts, engine and power, are usually coaxial, hence the name: turboshaft.
Compared to jet engine with a propellor directly attached via gearing, which is the turboprop.
(lot of words, but now you know a whole lot more about modern helo engines)
a lot of things are a win over the macbook air.
i'm still waiting for the proper aspect ratio to come back. this one is still that horrendous widescreen ration intended for movies and not work.
but if we can learnt o understand hers, we can learn to understand others. eventually a methodology to map and understand the brain in a living person, without surgery, could be the norm. alzheimers beings to set in? No problem. Step into the BRI machine for a few a hours, doc reads the results, then they apply a small implant to the precise relevant location of your unique brain to repair the malfunctioning communication relay.
Wrong about this topic too.
Man you just can't catch a break.
Few or no "regular" mass market car needs more than regular gas.
Some luxury or performance cars, with a high performance engine with high compression ratios, will run more efficiently with it, but even then its not required because of the anti-knock sensors that are standard and have been for a while now. you lose a little performance, but they adjust the timing.
Read the manual.
If it says the words "premium required" then fine, you might actually need it.
If says "recommended" or nothing at all, and this is the overwhelming majority of vehicles, then premium is a waste of $$.
http://auto.howstuffworks.com/premium-gas-luxury-vehicles.htm
http://lifehacker.com/5846880/should-i-use-premium-gas-in-my-car
also humourous of course is that the Mayor just issued some boilerplate response in defense of the council, not even aware the the gent is a (volunteer) member of that very same council.
It seems that the alternative journalist he ticked off is a volunteer member of hte same Council that he is a volunteer member of. She wrote some inflammatory things about his wife's charity group (dealing with special needs kids), he got ticked, said some things, and the journalist in turn threatened blackmail of the "stop saying bad things about me, or we'll stop covering your wife's charity in the press at all". he of course didnt take that lying down and criticized the hournalist more... ...and so now the journalist, in the name of hte council that they are both volunteer members of, contacted a lawyer and had the C&D sent.
So in the end the C&D Lawyer is a middleman in their dispute.
Now, he sent a very poorly written C&D and deserves all ridicule he has recieved on that (and failed in his own due diligence if he can so easily be trumped by such simple things as facts, as the shown in the response letter). but he was also just being used a pawn in the battle between the two individuals.
this is how it looks frm what ive found.
Again: Neither.
KKK member.
As it happens, they're KKK members.
http://www.cnn.com/2013/06/20/justice/new-york-x-ray-plot/index.html
KKK. Read the article on CNN.
you're not bursting anyone's bubble let alone mine. i have considerable experience in aviation maintenance, primarily military, to back me up.
even parts for new aircraft, for new civilian light aircraft, have a robustness to them you wont ever find in consumer electronics. its not merely a matter of being hard to get certified due to red tape clogging innovation.
I wish I could get a dose of Kardashian or three.
At the same time even!