I seldom call for people's jobs, but I'll make an exception in this case..
I agree! And I also seldom call for people to be fired.
But, just to be totally clear -- the person/people who should be fired is NOT the operator who selected the wrong drop-down box on the badly-designed UI. And NOT the one who coded it, either. The real culprit here is whoever reviewed, and approved the architecture. Probably a _much_ higher level person than the one who will most likely be blamed -- given what I know about typical government and corporate scapegoating habits.
OK, go ahead and mod me down for not RTFA'ing! If I'd read the original posting, I'd have realized they were referring to exactly the same Stanford study I just posted. Sorry!
The relative number of sedans versus extended cab trucks owned in a neighborhood, can be correlated with political leanings. Perhaps, substituting a survey of vehicles parked near a polling place makes for a better indicator still, because it reflects voter turnout?
lockout, exponential backoff, black- and greylists, IP fail2ban, rate limiting, fail advice, provisional (honeypot?) access and other tactics will increase attack costs. Yes, some of them becomes DoS, but all cracking essentially is exactly this.
Agreed! But don't go hog wild. Slowing down a password-guessing attack requires only a moderate amount of throttling. Extreme measures just piss off legitimate users.
A rate-limiting or exponential back off scheme can reasonably be capped at a few seconds, perhaps a few tens of seconds delay at most. And lockout is never justified. A 5 second delay will be tolerable for the casual user who types clumsily, yet is more than adequate to defend against a brute-force attack.
Always consider the frustrations experienced by a user with a motor coordination impairment -- say mild Parkinsons Disease. This user is otherwise more than capable of using online services, but will unavoidably enter more miss-typed passwords than the average user. Online services that set draconian lockout policies render themselves essentially unusable to such a user. (And YES, voip.ms with your 4 attempts limit triggering a 24-hour lockout -- I'm talking about you!).
Correct me if I am wrong (and if I am wrong, be gentle -- this is not my field of expertise!), but to me this sounds like a proof that the simulation we are in (if any) is not "recurseable".
Our universe cannot be simulated by a machine that "exists" within our universe, because that machine would have to be built within, and follow the physical rules of, our universe -- which are not rich enough to perform a self-simulation. Perhaps our universe CAN be simulated by a machine running in a hypothetical "real" universe, whose physical rules are less restrictive than our own.
To me this is (weakly) analogous to some forms of virtualization in computer science. A computer architecture may be used to run an emulation of a different virtualized computer architecture. The virtual architecture being emulated may have an entirely different, probably lesser set of capabilities -- not necessarily rich enough for it in turn to be capable of emulating a virtualized instance of its own architecture.
You are right, I was ignoring UberPool and LyftLine In part because I've never used them and only want to comment on things I've seen first hand. And, in part because their geographic availability seems so limited -- at least in my subjective far-from-the-taxi-ciities experience. Right now, I am in a small city of 200,000 population, for example, and neither of these services exist.
I was vaguely aware that in "taxi cities", some of the classic taxi problems you describe might be the case. Fixed supply trying to meet hugely variable demand seems like a recipe for failure. But again, I didn't want to comment on that, because I prefer to stick to the things I know about first hand -- namely how Uber and Lyft have totally changed the game in smaller cities and otherwise taxi-underserved areas. And there, their positive impact is huge.
(PS: There's no need to be so pre-emptively defensive about seeming like a troll. Nothing in you post looked remotely trollish to me!)
Uber and Lyft are far from perfect, and I certainly didn't mean to argue that conventional taxis are obsolete. Only that in my opinion, Uber and Lyft add huge value in taxi-underserved areas -- enough that for me at least, they change the game entirely.
Other replies to my original post seem to confirm that -- going further and saying that they are a game-changer in "taxi cities" too -- a fact that I was not aware of because I've personally seldom used either alternative in those cases.
Ok, I'll get my nitpick out of the way first: I've always hated the mis-application of the term "Ride Sharing" to Uber and Lyft. They have nothing to do with Ride Sharing. More like taxis, but I don't totally buy that equivalency either. Here's why.
For people who live in a "taxi city" like New York or Chicago or London, there really is very little difference between Uber, Lyft, a classic taxi, or a minicab. These are cities where a significant fraction of the populace uses taxis much of the time already. Here Uber and Lyft are additional players in the taxi economy, but they don't change the game one iota. I won't get into the politics of whether they are good or bad in these locales. That's not my soapbox.
But what about other locations? Smaller towns, or cities that were never traditionally taxi-centric -- where most folks own private cars and use them most of the time. Or in outer-lying suburbs of big cities that are poorly served by taxis. If you live in or frequently travel to such an area, you'll understand that Uber and Lyft really *have* changed the game -- by being truly distributed rather than depot-centric, and much more adaptive to demand. Call a convectional taxi, and the dispatch office will tell you it'll be 20 minutes. Call again an hour later, and the dispatch office will tell you 20 more minutes. Repeat another hour later, and once again the answer will be 20 more minutes. There's no way to ever know whether and when you'll get your ride. If and when the taxi ever shows up, the driver very likely doesn't know how to get to your destination, and speaks very little language in common with you, and besides by then you probably no longer want to go!
Uber and Lyft have fixed that (but not everywhere). There is now a relatively reliable service, that you can call at pretty much any time, and the estimated arrival times really are reliable, and usually pretty short, and if there will be a long wait, you know about it and can plan accordingly. And when there truly is nobody available, you know it -- you don't get strung along.
Even the dreaded surge pricing has not been a problem for me (so far). I've almost never had to pay it, and the few times I have haven't affected my long-term average cost much. I have occasionally gamed it, switching to Lyft when Uber is surged, and vice versa. Very surprisingly, that worked!
So, YMMV, but for me Uber and Lyft have indeed changed the game. For me, they've made me much less dependent upon rental cars when I travel, and have made other forms of public transit more viable too, by solving the "last mile problem".
There have been a couple of factually incorrect responses to my post, but I'll pick just this one to respond to.
You are correct that the Bernoulli principle applies to the mechanism by which above-versus-below pressure differential is created. You are entirely wrong in stating that this somehow does not mean air is accelerated downward. Air is indeed accelerated downwards, and in EXACTLY the amount dictated by F=ma. Anything else would be reactionless force, and even aerodynamicists are not exempt from newtons laws.
Bernoulli principle is NOT an alternative to Newtonian physics! You can't ignore either one just because you choose the other to explain the mechanicsm by which the air is displaced. Both explainations are equally valid, and exactly equivalent.
Yes an airplane wing has a longer upper path and a shorter lower path, and yes, that creates speed differential and thus pressure differential. But to create lift it also has to have a positive angle of attack - the angle between the chord of the wing and the so-called "relative wind". Without this, no pressure differential is created, no downward acceleration, and no lift.
Also, I should point out that in this regard there is no fundamental difference between fixed wing and rotor. A rotor is still a wing. Each blade still has a curvature and a positive angle of attack. It still creates upper/lower pressure differential with a little help from Bernoulli. It still accelerates air downwards as as result. It still generates upward force proportional to the product of mass and acceleration of downward-displaced air. The only difference between rotor and fixed is that rotor is configured to make its own relative wind (if motorized) and hence its ability to generate lift is not strictly tied to forward motion of the craft as a whole.
And replying to my own post with a slight topic drift. I am also somewhat skeptical (but less so) about Musk's alternatives.
Boring is a great solution where the cost can be justified, but I'm skeptical of the economies of scale that it's widespread adoption seems to depend upon. And, I'm highly skeptical of the safety proposition -- how do you rescue passengers from a stranded pod in an evacuated underground tube?
I really want Hyperloop to succeed. I'm just not sure I want to drink all the Kool Aid involved in becoming a true believer.:-)
I am a major skeptic about the whole flying-car idea. For many reasons, but not the same reasons as Musk. Here, I am disagreeing with one of Musk's points out of technical nit-pickery, but I DO agree with his overall conclusion that flying cars are not the right answer to personal transportation.
I agree they will be noisy. That will never be fully solved. (And expensive and unsafe, but that's off topic.) But, Musk's wind objection -- I just don't buy it.
Yes, aircraft generate lift by displacing air downwards. Some inclined plane (either the wings, or the rotor blades) deflects air downwards, creating an equal and opposite force upwards. So yes, all flying machines "create downward wind". Some do it highly efficiently (at optimum cruising speed, a typical fixed-wing plane or even to a lesser extent a helicopter). Some do it a little less efficiently (a fixed wing plane at very low airspeed), and some do it horribly inefficiently (a helicopter or drone hovering).
The efficiency is largely a function of the craft's forward speed through the air, for a very basic Newtonian reason. F = ma.
The upward FORCE (which must counterbalance the aircraft's weight) must be matched by downwards ACCELERATION of some MASS of air. Acceleration is not velocity, it is rate of change of velocity. Therefore, lift comes from the act of imparting new or increased downward velocity on some mass of air. Absolute velocity doesn't help, only increase in velocity. Hold that thought, we'll get back to it.
An aircraft moving forward horizontally encounters a steady supply of new air that does not yet have any vertical velocity. OTOH, once an aircraft that is hovering, has imparted downward velocity on a column of air, it remains within that accelerated column as it tries to accelerate more mass downwards. The established downward velocity of the air doesn't help, only the acceleration (increase) in downward velocity of some part of that air. To solidify this concept, think of "swimming up a waterfall".
Hopefully this illustrates why hovering is highly inefficient, and cruising is much more efficient.
Enter simple economics. Any economically VIABLE system of flying vehicles spends the minimum time hovering and the maximum time cruising. This is the reason helicopters are used only for specialized tasks or by rich people, while fixed wing planes are used for general transportation. While I don't personally believe that flying cars will take off (bad pun semi-intended), if they do, simple economics dictate that they won't spend much time milling around close to their terminals hovering. They will rapidly get a move on along their course. Once they are moving en-route, their "downward wind" is over such a dispersed area that is is essentially immeasurable.
I don't know what exact means they'll use to transition from takeoff to cruise -- rotors, fixed wings, adjustable wings, whatever -- but they won't be concentrating their "downward wind" in one small place for very long. If one's vision of personal air transportation involves any significant time hovering close to the terminal, then economics dictate that it won't succeed. And downward wind during cruise is simply not a problem.
There will be some localized wind right at the terminals, but if you've ever stood nearby when a helicopter takes off, you know that it is windy very strong but very localized, and does not persist long after the helicopter moves away.
The cost to personal liberty, the flagrant unconstitutionality, and the chilling effect on US international relations and tourism aside, this is ALSO a bad idea because it will have zero effect on the real bad guys.
If you are a bad guy, why would you bring a phone loaded with contacts? Why would you provide a real, rather than a fake social media account? For a real bad guy, it is trivially easy to circumvent this new check. For the rest of us, it's a massive inconvenience, invasion of privacy, and an almost certain invitation to both systematic abuse and abuse by bad-apple agents.
(BTW, topic drift... I was quite surprised to see financial data disclosure requirements described as "new". Unlike the phone search and social media stuff, the financial data part is _not_ new. It's been a requirement for certain visa applicants for at least 40 years. It doesn't currently happen at the border, but rather at visa application time. Perhaps the reason it's listed as being new is because it now includes visa-waiver-program countries too?)
This is just a semantic nitpick question about terminology. (I am not a chemist. Nor a physicist. So, humor me if this question is stupid.)
Should we think of Hydrogen as being metal -- one that happens to have been given a bad rap in the past because the "right" temperature/pressure point where it's metalic-ness would have been obvious, just happens not to be exactly common in our everyday experience. In the taxonomy of elements, isn't a given element on periodic table either considered a metal or not?
Or is hydrogen qualitatively different, somehow? e.g. is it semiconductor like Silicon?
Also, are there any other elements with metalic/non-metalic versions of (say) their solid states?
(The following are not recent, they are long-standing UI problems, but I think at least as serious as the others on the list.)
- Un-commanded/asynchronous change of focus. (E.g. popup appears, userping your current interaction with a window).
- Lack of context. (E.g. popup tells you there has been an error of type X, and offers some choices, but you have no way of even knowing which program or window the popup is assocated with. For bonus points, it asks you to choose a corrective aciton on the spot.)
- Missing or non-obvious way to "back out" of the previous action, if you decide you took a wrong turn. (Iphone is really bad this way, and the alleged fix in IOS9 doesn't really fix it.)
- User-interaction windows that "take you hostage". You have to click one of several irreversible choices before anything else can happen. Won't relinquish focus to go see explore options or understand the context better. Worst still, it can't even be dragged so you can look at the window below for context!
- Obscured boundary between executing the program and changing the configuration. "Do you want to do X?". "Do you always want to do X in future?" "Do you want to make XYZZY the default handler for X"?. Also, ambiguity about whether resulting changes are for the current operation, the current data set, the current session, or all future activities by the program.
- Ambiguity about which each choice means what. Does "proceed" mean proceed with the original operation you requested? Does it mean proceed with the corrective action suggested, e.g. in an error popup? A popular variation of this is "do you want to do X (yes/no)", with no explanation of what will be done instead if you select no.
Agreed with all of the above. Slight topic drift follows...
I've never bought or sold a Bitcoin, because they don't seem to offer any use case that I care about.
Certainly not investment. Not even under the banner of "speculation" -- that's not in my temperament (I don't like playing with the highly volatile) And not money-laundering either. What little money I do possess is sparkling clean, and not in need of any laundering.
But, is the following a useful use-case for Bitcoin?
Can you use Bitcoin useful as an interim currency to send money between family members in different countries? The sender would buy bit-coin in say dollars, send it electronically to the receiver, who would almost immediately sell it in euros, say. The Bitcoins would be held for a short enough time that hopefully the volatility would not be an unacceptable risk. Perhaps just minutes.
I would be interested in that use model, perhaps. I don't care about anonymity per-se, as the transfers would all be legal and well within regulatory limits. But, purely as a way to avoid dealing with foreign-exchange departments in banks, which I can tell you from experience are VERY very slow, complicated, and expensive. Seems like a Bitcoin-based transfer would essentially be self-directed, with nobody other than the sender and receiver having to play an active role.
> my house payment is $1000, it'll be $1000 in a fiat currency like US dollars, period. > But my house payment will be $1000 US dollars regardless of the price of gold or silver or bitcoin or whatever.
It's only "fixed" in dollars, because you negotiated in dollars when you took out the mortgage. (I'm not suggesting you had a choice, of course).
It's not "fixed" in any other fiat currency. Your $1000/mo mortgage payment still changes from month to month when measured in Euros, Yuan, Pounds, Shekels, Wampum, or Micronesian Rai stones.
So, I don't think this argument illustrates any fundamental fiat-vs-bitcoin difference. It only illustrates the pragmatic point that currency amounts specified in a contract have to be bound to a particular currency in order to make the contract unambiguous. That chosen currency (whether fiat or bitcoin) is only "special" in the context of that particular contract.
I am always suspicious of web sites that present only one interface -- something like "sign up here". No reading what the implications are first. No up-front disclosure of how to terminate the agreement if you change your mind. Basically, no information disclosed until you are already committed.
The web site appears to have a glaring omission. Provides for easy opt-in, but what about opt-out?
Suppose you own a property, and the previous owner was on the list. You buy a drone, and want to fly it on your own property. Oops!
Even if they fix that problem, and provide a way to remove an address from the list, there needs to be a robust way of ensuring that the change propagates quickly to new and existing drones.
The article is a little light and fluffy. Doesn't say how these passwords were leaked.
Seems likely, though, that the very fact that they were leaked at all might be a form of selection bias. For example if the leakage vector involved some sort of cracking, it is hardly surprising at all that simple passwords dominate the list.
I have lost four of my friends to airplane accidents. Two were pilots -- in one case the it clearly his own fault, and in the other it was extremely bad piece of luck. The other two deaths were the direct result of naively trusting the wrong pilot.
I see two flavors of comment so far. Non-pilots saying they think the idea is scary, and pilots saying "aw, pshaw, I am well trained, what is the problem?". Well, I am a pilot myself (commercial pilot and certified flight instructor), yet I strongly agree with the "that's scary" crowd. I've flown many thousands of hours in all sorts of locales, weather, and equipment. I've handled numerous emergencies, with never a scratch. I've taught hundreds of other pilots to fly. But, in all that time, by far the scariest moments I have ever had in the air were occasions where I made the mistake of riding as a passenger with the wrong choice of pilot!
Those who place their faith in the FAA's training standards, simply fail to understand that the ratings indicate compliance with the bare legal minima -- essentially they mean nearly nothing.
Nor does safety correlate with pilot rating. I've met some mere student pilots that I'd sooner trust with my life than many commercial pilots. The variation from one individual pilot to the next, regardless of qualifications, by far exceeds the variations from one rating to another. That variation comes from preparedness, attitude experience and common sense. Bottom line, with the exception of airlines (where I have no choice!) I will NEVER ride with a pilot whose experience, skills, and attitude I do not personally know first hand. And, I'd never advise friends or loved ones to ride with "just any old pilot".
Just for the heck of it, I tried searching for downloads of known 100% legal content -- Linux distributions, kernels etc.
Sure enough, there are people (well ok, IP addresses actually) accused of being thieves because they downloaded perfectly legal materials. Nowhere on Ter's web site did I see a single mention of the distinction between merely using file sharing (which is legal) and using it to violate copyright laws (which is not).
This distinction is apparently unknown to Suren Ter, or more likely deliberately ignored. His rhetoric clearly states that if you ever use file sharing, under any circumstances, you are a thief!
Slashdot Mirror
Anybody know?
YES. Mod parent up, please, anybody who has points!
I seldom call for people's jobs, but I'll make an exception in this case..
I agree! And I also seldom call for people to be fired.
But, just to be totally clear -- the person/people who should be fired is NOT the operator who selected the wrong drop-down box on the badly-designed UI. And NOT the one who coded it, either.
The real culprit here is whoever reviewed, and approved the architecture. Probably a _much_ higher level person than the one who will most likely be blamed -- given what I know about typical government and corporate scapegoating habits.
OK, go ahead and mod me down for not RTFA'ing!
If I'd read the original posting, I'd have realized they were referring to exactly the same Stanford study I just posted. Sorry!
Isn't this just a subtle exit poll?
The relative number of sedans versus extended cab trucks owned in a neighborhood, can be correlated with political leanings.
Perhaps, substituting a survey of vehicles parked near a polling place makes for a better indicator still, because it reflects voter turnout?
https://news.stanford.edu/2017...
lockout, exponential backoff, black- and greylists, IP fail2ban, rate limiting, fail advice, provisional (honeypot?) access and other tactics will increase attack costs. Yes, some of them becomes DoS, but all cracking essentially is exactly this.
Agreed! But don't go hog wild. Slowing down a password-guessing attack requires only a moderate amount of throttling. Extreme measures just piss off legitimate users.
A rate-limiting or exponential back off scheme can reasonably be capped at a few seconds, perhaps a few tens of seconds delay at most. And lockout is never justified. A 5 second delay will be tolerable for the casual user who types clumsily, yet is more than adequate to defend against a brute-force attack.
Always consider the frustrations experienced by a user with a motor coordination impairment -- say mild Parkinsons Disease. This user is otherwise more than capable of using online services, but will unavoidably enter more miss-typed passwords than the average user. Online services that set draconian lockout policies render themselves essentially unusable to such a user. (And YES, voip.ms with your 4 attempts limit triggering a 24-hour lockout -- I'm talking about you!).
Not allowed in prisons?
Then why call them cell phones?
Correct me if I am wrong (and if I am wrong, be gentle -- this is not my field of expertise!), but to me this sounds like a proof that the simulation we are in (if any) is not "recurseable".
Our universe cannot be simulated by a machine that "exists" within our universe, because that machine would have to be built within, and follow the physical rules of, our universe -- which are not rich enough to perform a self-simulation.
Perhaps our universe CAN be simulated by a machine running in a hypothetical "real" universe, whose physical rules are less restrictive than our own.
To me this is (weakly) analogous to some forms of virtualization in computer science. A computer architecture may be used to run an emulation of a different virtualized computer architecture. The virtual architecture being emulated may have an entirely different, probably lesser set of capabilities -- not necessarily rich enough for it in turn to be capable of emulating a virtualized instance of its own architecture.
You are right, I was ignoring UberPool and LyftLine In part because I've never used them and only want to comment on things I've seen first hand. And, in part because their geographic availability seems so limited -- at least in my subjective far-from-the-taxi-ciities experience. Right now, I am in a small city of 200,000 population, for example, and neither of these services exist.
I was vaguely aware that in "taxi cities", some of the classic taxi problems you describe might be the case. Fixed supply trying to meet hugely variable demand seems like a recipe for failure. But again, I didn't want to comment on that, because I prefer to stick to the things I know about first hand -- namely how Uber and Lyft have totally changed the game in smaller cities and otherwise taxi-underserved areas. And there, their positive impact is huge.
(PS: There's no need to be so pre-emptively defensive about seeming like a troll. Nothing in you post looked remotely trollish to me!)
Uber and Lyft are far from perfect, and I certainly didn't mean to argue that conventional taxis are obsolete. Only that in my opinion, Uber and Lyft add huge value in taxi-underserved areas -- enough that for me at least, they change the game entirely.
Other replies to my original post seem to confirm that -- going further and saying that they are a game-changer in "taxi cities" too -- a fact that I was not aware of because I've personally seldom used either alternative in those cases.
Ok, I'll get my nitpick out of the way first: I've always hated the mis-application of the term "Ride Sharing" to Uber and Lyft. They have nothing to do with Ride Sharing. More like taxis, but I don't totally buy that equivalency either. Here's why.
For people who live in a "taxi city" like New York or Chicago or London, there really is very little difference between Uber, Lyft, a classic taxi, or a minicab. These are cities where a significant fraction of the populace uses taxis much of the time already. Here Uber and Lyft are additional players in the taxi economy, but they don't change the game one iota. I won't get into the politics of whether they are good or bad in these locales. That's not my soapbox.
But what about other locations? Smaller towns, or cities that were never traditionally taxi-centric -- where most folks own private cars and use them most of the time. Or in outer-lying suburbs of big cities that are poorly served by taxis. If you live in or frequently travel to such an area, you'll understand that Uber and Lyft really *have* changed the game -- by being truly distributed rather than depot-centric, and much more adaptive to demand. Call a convectional taxi, and the dispatch office will tell you it'll be 20 minutes. Call again an hour later, and the dispatch office will tell you 20 more minutes. Repeat another hour later, and once again the answer will be 20 more minutes. There's no way to ever know whether and when you'll get your ride. If and when the taxi ever shows up, the driver very likely doesn't know how to get to your destination, and speaks very little language in common with you, and besides by then you probably no longer want to go!
Uber and Lyft have fixed that (but not everywhere). There is now a relatively reliable service, that you can call at pretty much any time, and the estimated arrival times really are reliable, and usually pretty short, and if there will be a long wait, you know about it and can plan accordingly. And when there truly is nobody available, you know it -- you don't get strung along.
Even the dreaded surge pricing has not been a problem for me (so far). I've almost never had to pay it, and the few times I have haven't affected my long-term average cost much. I have occasionally gamed it, switching to Lyft when Uber is surged, and vice versa. Very surprisingly, that worked!
So, YMMV, but for me Uber and Lyft have indeed changed the game. For me, they've made me much less dependent upon rental cars when I travel, and have made other forms of public transit more viable too, by solving the "last mile problem".
I'd like to see more players in the game, though.
There have been a couple of factually incorrect responses to my post, but I'll pick just this one to respond to.
You are correct that the Bernoulli principle applies to the mechanism by which above-versus-below pressure differential is created. You are entirely wrong in stating that this somehow does not mean air is accelerated downward. Air is indeed accelerated downwards, and in EXACTLY the amount dictated by F=ma. Anything else would be reactionless force, and even aerodynamicists are not exempt from newtons laws.
Bernoulli principle is NOT an alternative to Newtonian physics! You can't ignore either one just because you choose the other to explain the mechanicsm by which the air is displaced. Both explainations are equally valid, and exactly equivalent.
Yes an airplane wing has a longer upper path and a shorter lower path, and yes, that creates speed differential and thus pressure differential. But to create lift it also has to have a positive angle of attack - the angle between the chord of the wing and the so-called "relative wind". Without this, no pressure differential is created, no downward acceleration, and no lift.
Also, I should point out that in this regard there is no fundamental difference between fixed wing and rotor. A rotor is still a wing. Each blade still has a curvature and a positive angle of attack. It still creates upper/lower pressure differential with a little help from Bernoulli. It still accelerates air downwards as as result. It still generates upward force proportional to the product of mass and acceleration of downward-displaced air. The only difference between rotor and fixed is that rotor is configured to make its own relative wind (if motorized) and hence its ability to generate lift is not strictly tied to forward motion of the craft as a whole.
And replying to my own post with a slight topic drift. I am also somewhat skeptical (but less so) about Musk's alternatives.
Boring is a great solution where the cost can be justified, but I'm skeptical of the economies of scale that it's widespread adoption seems to depend upon. And, I'm highly skeptical of the safety proposition -- how do you rescue passengers from a stranded pod in an evacuated underground tube?
I really want Hyperloop to succeed. I'm just not sure I want to drink all the Kool Aid involved in becoming a true believer. :-)
I am a major skeptic about the whole flying-car idea. For many reasons, but not the same reasons as Musk.
Here, I am disagreeing with one of Musk's points out of technical nit-pickery, but I DO agree with his overall conclusion that flying cars are not the right answer to personal transportation.
I agree they will be noisy. That will never be fully solved. (And expensive and unsafe, but that's off topic.)
But, Musk's wind objection -- I just don't buy it.
Yes, aircraft generate lift by displacing air downwards. Some inclined plane (either the wings, or the rotor blades) deflects air downwards, creating an equal and opposite force upwards. So yes, all flying machines "create downward wind". Some do it highly efficiently (at optimum cruising speed, a typical fixed-wing plane or even to a lesser extent a helicopter). Some do it a little less efficiently (a fixed wing plane at very low airspeed), and some do it horribly inefficiently (a helicopter or drone hovering).
The efficiency is largely a function of the craft's forward speed through the air, for a very basic Newtonian reason. F = ma.
The upward FORCE (which must counterbalance the aircraft's weight) must be matched by downwards ACCELERATION of some MASS of air. Acceleration is not velocity, it is rate of change of velocity. Therefore, lift comes from the act of imparting new or increased downward velocity on some mass of air. Absolute velocity doesn't help, only increase in velocity. Hold that thought, we'll get back to it.
An aircraft moving forward horizontally encounters a steady supply of new air that does not yet have any vertical velocity. OTOH, once an aircraft that is hovering, has imparted downward velocity on a column of air, it remains within that accelerated column as it tries to accelerate more mass downwards. The established downward velocity of the air doesn't help, only the acceleration (increase) in downward velocity of some part of that air. To solidify this concept, think of "swimming up a waterfall".
Hopefully this illustrates why hovering is highly inefficient, and cruising is much more efficient.
Enter simple economics. Any economically VIABLE system of flying vehicles spends the minimum time hovering and the maximum time cruising. This is the reason helicopters are used only for specialized tasks or by rich people, while fixed wing planes are used for general transportation. While I don't personally believe that flying cars will take off (bad pun semi-intended), if they do, simple economics dictate that they won't spend much time milling around close to their terminals hovering. They will rapidly get a move on along their course. Once they are moving en-route, their "downward wind" is over such a dispersed area that is is essentially immeasurable.
I don't know what exact means they'll use to transition from takeoff to cruise -- rotors, fixed wings, adjustable wings, whatever -- but they won't be concentrating their "downward wind" in one small place for very long. If one's vision of personal air transportation involves any significant time hovering close to the terminal, then economics dictate that it won't succeed. And downward wind during cruise is simply not a problem.
There will be some localized wind right at the terminals, but if you've ever stood nearby when a helicopter takes off, you know that it is windy very strong but very localized, and does not persist long after the helicopter moves away.
The cost to personal liberty, the flagrant unconstitutionality, and the chilling effect on US international relations and tourism aside, this is ALSO a bad idea because it will have zero effect on the real bad guys.
If you are a bad guy, why would you bring a phone loaded with contacts? Why would you provide a real, rather than a fake social media account? For a real bad guy, it is trivially easy to circumvent this new check. For the rest of us, it's a massive inconvenience, invasion of privacy, and an almost certain invitation to both systematic abuse and abuse by bad-apple agents.
(BTW, topic drift... I was quite surprised to see financial data disclosure requirements described as "new". Unlike the phone search and social media stuff, the financial data part is _not_ new. It's been a requirement for certain visa applicants for at least 40 years. It doesn't currently happen at the border, but rather at visa application time. Perhaps the reason it's listed as being new is because it now includes visa-waiver-program countries too?)
This is just a semantic nitpick question about terminology. (I am not a chemist. Nor a physicist. So, humor me if this question is stupid.)
Should we think of Hydrogen as being metal -- one that happens to have been given a bad rap in the past because the "right" temperature/pressure point where it's metalic-ness would have been obvious, just happens not to be exactly common in our everyday experience. In the taxonomy of elements, isn't a given element on periodic table either considered a metal or not?
Or is hydrogen qualitatively different, somehow? e.g. is it semiconductor like Silicon?
Also, are there any other elements with metalic/non-metalic versions of (say) their solid states?
Also:
(The following are not recent, they are long-standing UI problems, but I think at least as serious as the others on the list.)
- Un-commanded/asynchronous change of focus. (E.g. popup appears, userping your current interaction with a window).
- Lack of context. (E.g. popup tells you there has been an error of type X, and offers some choices, but you have no way of even knowing which program or window the popup is assocated with. For bonus points, it asks you to choose a corrective aciton on the spot.)
- Missing or non-obvious way to "back out" of the previous action, if you decide you took a wrong turn. (Iphone is really bad this way, and the alleged fix in IOS9 doesn't really fix it.)
- User-interaction windows that "take you hostage". You have to click one of several irreversible choices before anything else can happen. Won't relinquish focus to go see explore options or understand the context better. Worst still, it can't even be dragged so you can look at the window below for context!
- Obscured boundary between executing the program and changing the configuration. "Do you want to do X?". "Do you always want to do X in future?" "Do you want to make XYZZY the default handler for X"?. Also, ambiguity about whether resulting changes are for the current operation, the current data set, the current session, or all future activities by the program.
- Ambiguity about which each choice means what. Does "proceed" mean proceed with the original operation you requested? Does it mean proceed with the corrective action suggested, e.g. in an error popup? A popular variation of this is "do you want to do X (yes/no)", with no explanation of what will be done instead if you select no.
Agreed with all of the above. Slight topic drift follows...
I've never bought or sold a Bitcoin, because they don't seem to offer any use case that I care about.
Certainly not investment. Not even under the banner of "speculation" -- that's not in my temperament (I don't like playing with the highly volatile)
And not money-laundering either. What little money I do possess is sparkling clean, and not in need of any laundering.
But, is the following a useful use-case for Bitcoin?
Can you use Bitcoin useful as an interim currency to send money between family members in different countries? The sender would buy bit-coin in say dollars, send it electronically to the receiver, who would almost immediately sell it in euros, say. The Bitcoins would be held for a short enough time that hopefully the volatility would not be an unacceptable risk. Perhaps just minutes.
I would be interested in that use model, perhaps. I don't care about anonymity per-se, as the transfers would all be legal and well within regulatory limits. But, purely as a way to avoid dealing with foreign-exchange departments in banks, which I can tell you from experience are VERY very slow, complicated, and expensive. Seems like a Bitcoin-based transfer would essentially be self-directed, with nobody other than the sender and receiver having to play an active role.
Thoughts?
> my house payment is $1000, it'll be $1000 in a fiat currency like US dollars, period.
> But my house payment will be $1000 US dollars regardless of the price of gold or silver or bitcoin or whatever.
It's only "fixed" in dollars, because you negotiated in dollars when you took out the mortgage. (I'm not suggesting you had a choice, of course).
It's not "fixed" in any other fiat currency. Your $1000/mo mortgage payment still changes from month to month when measured in Euros, Yuan, Pounds, Shekels, Wampum, or Micronesian Rai stones.
So, I don't think this argument illustrates any fundamental fiat-vs-bitcoin difference.
It only illustrates the pragmatic point that currency amounts specified in a contract have to be bound to a particular currency in order to make the contract unambiguous. That chosen currency (whether fiat or bitcoin) is only "special" in the context of that particular contract.
Must be a slow news day, I guess.
I am always suspicious of web sites that present only one interface -- something like "sign up here". No reading what the implications are first. No up-front disclosure of how to terminate the agreement if you change your mind. Basically, no information disclosed until you are already committed.
The web site appears to have a glaring omission. Provides for easy opt-in, but what about opt-out?
Suppose you own a property, and the previous owner was on the list. You buy a drone, and want to fly it on your own property. Oops!
Even if they fix that problem, and provide a way to remove an address from the list, there needs to be a robust way of ensuring that the change propagates quickly to new and existing drones.
Seems very half-baked and gimmicky to me.
The article is a little light and fluffy. Doesn't say how these passwords were leaked.
Seems likely, though, that the very fact that they were leaked at all might be a form of selection bias. For example if the leakage vector involved some sort of cracking, it is hardly surprising at all that simple passwords dominate the list.
I have lost four of my friends to airplane accidents. Two were pilots -- in one case the it clearly his own fault, and in the other it was extremely bad piece of luck. The other two deaths were the direct result of naively trusting the wrong pilot.
I see two flavors of comment so far. Non-pilots saying they think the idea is scary, and pilots saying "aw, pshaw, I am well trained, what is the problem?". Well, I am a pilot myself (commercial pilot and certified flight instructor), yet I strongly agree with the "that's scary" crowd. I've flown many thousands of hours in all sorts of locales, weather, and equipment. I've handled numerous emergencies, with never a scratch. I've taught hundreds of other pilots to fly. But, in all that time, by far the scariest moments I have ever had in the air were occasions where I made the mistake of riding as a passenger with the wrong choice of pilot!
Those who place their faith in the FAA's training standards, simply fail to understand that the ratings indicate compliance with the bare legal minima -- essentially they mean nearly nothing.
Nor does safety correlate with pilot rating. I've met some mere student pilots that I'd sooner trust with my life than many commercial pilots. The variation from one individual pilot to the next, regardless of qualifications, by far exceeds the variations from one rating to another. That variation comes from preparedness, attitude experience and common sense. Bottom line, with the exception of airlines (where I have no choice!) I will NEVER ride with a pilot whose experience, skills, and attitude I do not personally know first hand. And, I'd never advise friends or loved ones to ride with "just any old pilot".
Not another one!
Browse this list before you get too excited about this development.
http://en.wikipedia.org/wiki/Comparison_of_personal_aerial_vehicles
Just for the heck of it, I tried searching for downloads of known 100% legal content -- Linux distributions, kernels etc.
Sure enough, there are people (well ok, IP addresses actually) accused of being thieves because they downloaded perfectly legal materials. Nowhere on Ter's web site did I see a single mention of the distinction between merely using file sharing (which is legal) and using it to violate copyright laws (which is not).
This distinction is apparently unknown to Suren Ter, or more likely deliberately ignored. His rhetoric clearly states that if you ever use file sharing, under any circumstances, you are a thief!
What a bozo!