"This era of terrorism" The actual prevalence of terror attacks is still quite low, despite all the press it garners. The train system can be attacked just about as easily as a hyperloop system would be.
I'm not sure whether an attack on a train or hyperloop would lead to a more impressive failure - trains in the US travel much slower, but there are a lot of super long trains. Hyperloop being automated could potentially have a greater number of smaller "pod" trains. With appropriate safety margin a single attack point could probably only kill the passengers in a single pod.
A chain reaction... right. The engineers surely wouldn't think to add any failsafe features which may include safety airlocks along the tube, mechanical brakes to hold the pod to the tube, etc.
Why on earth would you think this is a valid analogy? Yes, anything structural can "crunch pretty easily" when subject to loads far out of spec.
There's always safety margin in a design, and accounting for multiple possible scenarios, but the point of engineering is to come up with an efficient design based on the usage scenario.They could over-design the tanks to endure vacuum/pressure loads but then they'd cost more, waste more fuel trucking them around, and provide no benefit in the intended usage scenario.
A hyperloop would tube, like every other structure, would be designed for loading in a variety of anticipated scenarios plus safety margin. Since it involves human transport there would be increased testing and increased safety margin.
Well they are ramping up, which is hugely capital intensive. And so far demand for Tesla cars has been very high relative to the supply. So what's the problem?
Tesla might still fail but they're just following the same plan they've had all along for growing the company and producing a more affordable (but good) electric car.
That plan is why investors have put in the money necessary for Tesla to try this out which enables them to operate at a loss for several years.
Why would I want to drive to the store to buy a digital file on a disc (which might not even be in stock) instead of downloading it or streaming it from the comfort of my home? I already have beer and popcorn kernels at home.
Yes it pushes the limits of current home internet in many US locales for streaming, but that's a solvable problem with better home internet or pre-downloading.
There's no need to use a laser beam, you can use an omnidirectional light and superimpose a small signal which is invisible to the eye on top of room lighting. LEDs can be use but the data rate is lower. Laser diodes are actually being explored for lighting, they are already used in some car headlights and maybe other specialized applications, and they will support gigabit modulation rates.
Actually the 60 GHz band was selected precisely because the propagation loss is especially high here which reduces interference between adjacent users. Even though transmit powers must be higher for a given range and data rate the higher loss still translates into smaller adjacent user interference once you're outside of the range.
The problem is that it's challenging (i.e. expensive) to get useful range at this high frequency at high data rates where generating power is more difficult and where the propagation loss is higher.
The difference is that Apple's sales volume is over 100 million units per year, while Tesla's is under 100 thousand.
Apple's volume is 1,000 times greater than Tesla's so they are pretty much maxing out economy of scale on each hardware version. In fact in some cases they go beyond economies of scale when their suppliers can't meet this enormous demand, so producing multiple hardware versions can actually lower their manufacturing cost.
Tesla's volume is low enough that they derive additional economy of scale from reducing the number of hardware versions that they manufacture.
I used to be, like you, annoyed about this style of producing one hardware item and then software-limiting the feature set.
But then I understood that this is just price discrimination plus economies of scale - and being able to sell more cars at different feature levels with different levels of margin increases the overall sales volume by opening the car up to less wealthy consumers, while streamlining manufacturing, both of which improve economies of scale and reduce marginal cost which should translate into lower prices.
Even if the efficiency benefits don't translate into price benefits for the consumer - so what? You got what you paid for. If you're not happy then buy your electric luxury car from somebody else.
Executive orders are by nature fleeting as they are not law. A new President can undo orders much faster than Congress can reverse laws. DACA was a stop-gap measure to "defer action", and give time for Congress to make it permanent by putting its ideas into law. The Republican Congress had no interest in doing so (unfortunate in my opinion), so it's hardly surpising that DACA is now being reversed.
Plus DACA was on legally shaky ground from the beginning. Even if we agree with a President their power should still be limited because we might not agree with the next President.
The left refuses to even acknowledged he won and is an impediment to progress at every turn.
Don't exaggerate. Virtually everybody on the left acknowledges that he won, we're just unhappy about it.
And of course we are asking our representatives in Congress to do everything that they can to block his agenda... the President is not a king and cannot rule like a dictator.
You know that the Gates foundation also does a lot of work in the US right? And it buys things from taxpaying US companies, funds research in the US through grants, and directly employs US taxpayers. The US sees direct benefits from his foundation.
Further, he is absolutely free to direct his foundations priorities in the areas where he wants to make an impact, so long as the foundation keeps meeting the IRS definition of a charitable non-profit. It's all charitable work so it's tax exempt the same as every other charitable organization.
I don't see what there is to complain about when the Gates foundation is treated the exact same way as any other charitable non-profit.
While California wanted more low-emission and zero-emission cars they didn't want to force manufacturers to make them. Therefore manufacturers who didn't meet requirements for percentages of low/zero emission vehicles are allowed to purchase credits from manufacturers (like Tesla) who exceeded the government's requirements so that the manufacturer doesn't need to pay a penalty.
Because there is a free market for these credits the price varies, and the price is thus set by the supply and demand. Because of the slow ramp up of CA's emissions requirements the price is currently below what the cost of the penalty would be for a manufacturer to fail to meet the requirements (or buy credits).
It's not even clear to me that SpaceX has ever received a government subsidy.
People seem to get up in arms about the government spending money on SpaceX launches and think that it's a government subsidy, but they forget that the US government is the single biggest customer of space launch services in the world. Any rocket company who isn't selling to the US govt is missing out on a big piece of the pie.
They have received commercial crew development contracts from NASA, which is similar to contracts paid by NASA to contractors to develop the space shuttle (for example) although the commercial crew program is run somewhat differently from standard cost plus government aerospace contracting. These NASA contracts require performing to milestones to stay in the game and unlock future funding, and will ultimately lead to a capability NASA will purchase (as the sole initial customer) to launch crew to the ISS.
If an error happened because of some kind of gross negligence or deliberate misconduct like then an investigation would be conducted and appropriate people held to account. For example if management (or engineers) covered up test results indicating a problem to avoid delaying a product release then whoever covered up the test results would be culpable. There is lots of case law in this area in for example factory robots, medical equipment, and even today's car industry.
Is it expensive? Yes. But so is the current power industry. If cheaper options exist for sustainable energy storage (as you suggest) then they will eventually prevail against current options. But pumped hydro is mostly played out (and hydro usually causes massive habitat destruction) and other energy storage options tend to have drawbacks. Maybe another battery chemistry like sodium air will win.
Second, while I'm an EE I do deal with vacuum systems in my day job, I do respect them and understand that there are risks, and in any system where energy is stored. I also understand that a tanker which isn't designed to hold that pressure is totally different from a system designed to do a job. There are big vacuum systems all over the world, and big pressurized systems all over the world.
My point is twofold: 1) A vacuum with a ~14psi pressure differential is less dangerous than an equivalent pressurized system with a much larger pressure difference. 2) Although hyperloop would be the largest such vacuum system in the world, the design of systems designed to hold vacuum or positive pressure is very well understood and thus it can be undertaken safely.
Implosion bomb? What makes you think that a vacuum chamber (~14psi) will implode with bomb-like force in the event of an implosion?
Humans have built plenty of infrastructure operating at much higher pressure differentials (like water, gas, and oil pipelines) than the paltry pressure of a vacuum.
I really don't understand how liability can be "too great". All businesses involves risk, sometimes massive risk, but by testing and qualifying designs that risk can be reduced to the extent which is reasonable. Most of the remaining small risk is dealt with via insurance. If the cost of that insurance exceeds what a consumer can pay for a product then the product is not sold.
Liability exceeding the insurance policy or not covered by the insurance is dealt with by pursuing company assets to the point of bankruptcy if it reaches that point. Criminal charges could probably be filed if gross negligence led to a massive safety defect.
The riskiest thing for a car company would be to not sell self-driving cars since that will already guarantee them to eventually go out of business.
The ground based VLF antennas have efficiency in the 10-50%, and so radiated power levels appear to be in the kilowatt to low megawatt range, according to the Wikipedia article: https://en.wikipedia.org/wiki/...
Of course children are worth more than adults. Children have most of their life ahead of them. Harm in earlier years is compounded across the majority of their lifetime. Further, abuse during developmental years can have a much deeper impact. So couple the deeper impact of the crimes with the longer period of impact and it is quite obvious why we would consider the same crime to be worse when committed against a child.
Obviously there are emotional factors - it is natural and probably a result of evolution for us to be protective of children, and so we are. But there is a clear objective justification in addition to the emotional one.
It really doesn't, the comparison you cite does not apply to this "flying car" on multiple levels.
First, the article (and paper it's based on) is comparing typical mass transmit commuter planes versus typical car usage with an average of about 1.4 passengers per car. One of the big drivers of increased efficiency in flying is filling planes much closer to capacity, along with making the planes themselves far more efficient by design and by reducing speed slightly. The "flying cars" discussed here seems targeted for single-digit passenger numbers, and the present prototype only has seating for one: the pilot. It's closer to a "flying motorcycle" than a "flying car" (except I'd bet the motorcycle is faster than this).
Second, the comment you're replying to is mentioning the huge efficiency difference between planes and multicopters. Helicopters and multicopters ("rotary wing aircraft") are less efficient than planes ("fixed wing aircraft") because they travel more slowly while still needing to generate continuous lift, and they are less aerodynamic than planes. The article you're citing is discussing efficiency in planes, not heli-/multi-copters.
The truth is that it's just as easy to make that cup of coffee with an Aeropress, especially if you have an electric tea kettle, and it's a hell of a lot cheaper.
It really isn't as easy. I'm not saying using an Aeropress is hard. I own one myself and I think it's a great product. But if we use a car analogy an Aeropress is like a manual transmission, and a Keurig is like an automatic. It's not hard to see why people would be attracted to that ease - especially early in the morning before they've had coffee.
I decided to do a bit of searching, and found this detailed article which has some photos of the contents inside the pouches: http://www.businessinsider.com...
So it contains "chopped" vegetables, but it's actually already pretty finely shredded for the greens. It looks like the fruit chunks are a bit bigger in size. So this is not fully juiced, but it's about halfway there.
The bags are not filled with juice, they are filled with pre-chopped fruit and/or vegetable pieces. Or at least that's the idea behind the bags. I have a little difficulty believing that you could hand squeeze vegetables as effectively as a machine, but fruit should be easy enough.
But at $5-8 per bag, a $400 machine or one to two minutes of hand squeezing I don't really find this compelling. I'm sure the juice is delicious but it costs more than I spend on my whole lunch.
Slashdot Mirror
"This era of terrorism" The actual prevalence of terror attacks is still quite low, despite all the press it garners. The train system can be attacked just about as easily as a hyperloop system would be.
I'm not sure whether an attack on a train or hyperloop would lead to a more impressive failure - trains in the US travel much slower, but there are a lot of super long trains. Hyperloop being automated could potentially have a greater number of smaller "pod" trains. With appropriate safety margin a single attack point could probably only kill the passengers in a single pod.
A chain reaction... right. The engineers surely wouldn't think to add any failsafe features which may include safety airlocks along the tube, mechanical brakes to hold the pod to the tube, etc.
Why on earth would you think this is a valid analogy? Yes, anything structural can "crunch pretty easily" when subject to loads far out of spec.
There's always safety margin in a design, and accounting for multiple possible scenarios, but the point of engineering is to come up with an efficient design based on the usage scenario.They could over-design the tanks to endure vacuum/pressure loads but then they'd cost more, waste more fuel trucking them around, and provide no benefit in the intended usage scenario.
A hyperloop would tube, like every other structure, would be designed for loading in a variety of anticipated scenarios plus safety margin. Since it involves human transport there would be increased testing and increased safety margin.
Well they are ramping up, which is hugely capital intensive. And so far demand for Tesla cars has been very high relative to the supply. So what's the problem?
Tesla might still fail but they're just following the same plan they've had all along for growing the company and producing a more affordable (but good) electric car.
That plan is why investors have put in the money necessary for Tesla to try this out which enables them to operate at a loss for several years.
Why would I want to drive to the store to buy a digital file on a disc (which might not even be in stock) instead of downloading it or streaming it from the comfort of my home? I already have beer and popcorn kernels at home.
Yes it pushes the limits of current home internet in many US locales for streaming, but that's a solvable problem with better home internet or pre-downloading.
There's no need to use a laser beam, you can use an omnidirectional light and superimpose a small signal which is invisible to the eye on top of room lighting. LEDs can be use but the data rate is lower. Laser diodes are actually being explored for lighting, they are already used in some car headlights and maybe other specialized applications, and they will support gigabit modulation rates.
Actually the 60 GHz band was selected precisely because the propagation loss is especially high here which reduces interference between adjacent users. Even though transmit powers must be higher for a given range and data rate the higher loss still translates into smaller adjacent user interference once you're outside of the range.
The problem is that it's challenging (i.e. expensive) to get useful range at this high frequency at high data rates where generating power is more difficult and where the propagation loss is higher.
The difference is that Apple's sales volume is over 100 million units per year, while Tesla's is under 100 thousand.
Apple's volume is 1,000 times greater than Tesla's so they are pretty much maxing out economy of scale on each hardware version. In fact in some cases they go beyond economies of scale when their suppliers can't meet this enormous demand, so producing multiple hardware versions can actually lower their manufacturing cost.
Tesla's volume is low enough that they derive additional economy of scale from reducing the number of hardware versions that they manufacture.
I used to be, like you, annoyed about this style of producing one hardware item and then software-limiting the feature set.
But then I understood that this is just price discrimination plus economies of scale - and being able to sell more cars at different feature levels with different levels of margin increases the overall sales volume by opening the car up to less wealthy consumers, while streamlining manufacturing, both of which improve economies of scale and reduce marginal cost which should translate into lower prices.
Even if the efficiency benefits don't translate into price benefits for the consumer - so what? You got what you paid for. If you're not happy then buy your electric luxury car from somebody else.
Executive orders are by nature fleeting as they are not law. A new President can undo orders much faster than Congress can reverse laws. DACA was a stop-gap measure to "defer action", and give time for Congress to make it permanent by putting its ideas into law. The Republican Congress had no interest in doing so (unfortunate in my opinion), so it's hardly surpising that DACA is now being reversed.
Plus DACA was on legally shaky ground from the beginning. Even if we agree with a President their power should still be limited because we might not agree with the next President.
Don't exaggerate. Virtually everybody on the left acknowledges that he won, we're just unhappy about it.
And of course we are asking our representatives in Congress to do everything that they can to block his agenda... the President is not a king and cannot rule like a dictator.
You know that the Gates foundation also does a lot of work in the US right? And it buys things from taxpaying US companies, funds research in the US through grants, and directly employs US taxpayers. The US sees direct benefits from his foundation.
Further, he is absolutely free to direct his foundations priorities in the areas where he wants to make an impact, so long as the foundation keeps meeting the IRS definition of a charitable non-profit. It's all charitable work so it's tax exempt the same as every other charitable organization.
I don't see what there is to complain about when the Gates foundation is treated the exact same way as any other charitable non-profit.
While California wanted more low-emission and zero-emission cars they didn't want to force manufacturers to make them. Therefore manufacturers who didn't meet requirements for percentages of low/zero emission vehicles are allowed to purchase credits from manufacturers (like Tesla) who exceeded the government's requirements so that the manufacturer doesn't need to pay a penalty.
Because there is a free market for these credits the price varies, and the price is thus set by the supply and demand. Because of the slow ramp up of CA's emissions requirements the price is currently below what the cost of the penalty would be for a manufacturer to fail to meet the requirements (or buy credits).
It's not even clear to me that SpaceX has ever received a government subsidy.
People seem to get up in arms about the government spending money on SpaceX launches and think that it's a government subsidy, but they forget that the US government is the single biggest customer of space launch services in the world. Any rocket company who isn't selling to the US govt is missing out on a big piece of the pie.
They have received commercial crew development contracts from NASA, which is similar to contracts paid by NASA to contractors to develop the space shuttle (for example) although the commercial crew program is run somewhat differently from standard cost plus government aerospace contracting. These NASA contracts require performing to milestones to stay in the game and unlock future funding, and will ultimately lead to a capability NASA will purchase (as the sole initial customer) to launch crew to the ISS.
If an error happened because of some kind of gross negligence or deliberate misconduct like then an investigation would be conducted and appropriate people held to account. For example if management (or engineers) covered up test results indicating a problem to avoid delaying a product release then whoever covered up the test results would be culpable. There is lots of case law in this area in for example factory robots, medical equipment, and even today's car industry.
A single factory is not intended to. But Tesla projects that 100 gigafactories would meet demand for 100% world-wide renewable energy.
Is it expensive? Yes. But so is the current power industry. If cheaper options exist for sustainable energy storage (as you suggest) then they will eventually prevail against current options. But pumped hydro is mostly played out (and hydro usually causes massive habitat destruction) and other energy storage options tend to have drawbacks. Maybe another battery chemistry like sodium air will win.
"you fucking monkey" First off, LOL at this!
Second, while I'm an EE I do deal with vacuum systems in my day job, I do respect them and understand that there are risks, and in any system where energy is stored. I also understand that a tanker which isn't designed to hold that pressure is totally different from a system designed to do a job. There are big vacuum systems all over the world, and big pressurized systems all over the world.
My point is twofold:
1) A vacuum with a ~14psi pressure differential is less dangerous than an equivalent pressurized system with a much larger pressure difference.
2) Although hyperloop would be the largest such vacuum system in the world, the design of systems designed to hold vacuum or positive pressure is very well understood and thus it can be undertaken safely.
Implosion bomb? What makes you think that a vacuum chamber (~14psi) will implode with bomb-like force in the event of an implosion?
Humans have built plenty of infrastructure operating at much higher pressure differentials (like water, gas, and oil pipelines) than the paltry pressure of a vacuum.
I really don't understand how liability can be "too great". All businesses involves risk, sometimes massive risk, but by testing and qualifying designs that risk can be reduced to the extent which is reasonable. Most of the remaining small risk is dealt with via insurance. If the cost of that insurance exceeds what a consumer can pay for a product then the product is not sold.
Liability exceeding the insurance policy or not covered by the insurance is dealt with by pursuing company assets to the point of bankruptcy if it reaches that point. Criminal charges could probably be filed if gross negligence led to a massive safety defect.
The riskiest thing for a car company would be to not sell self-driving cars since that will already guarantee them to eventually go out of business.
The ground based VLF antennas have efficiency in the 10-50%, and so radiated power levels appear to be in the kilowatt to low megawatt range, according to the Wikipedia article: https://en.wikipedia.org/wiki/...
Of course children are worth more than adults. Children have most of their life ahead of them. Harm in earlier years is compounded across the majority of their lifetime. Further, abuse during developmental years can have a much deeper impact. So couple the deeper impact of the crimes with the longer period of impact and it is quite obvious why we would consider the same crime to be worse when committed against a child.
Obviously there are emotional factors - it is natural and probably a result of evolution for us to be protective of children, and so we are. But there is a clear objective justification in addition to the emotional one.
It really doesn't, the comparison you cite does not apply to this "flying car" on multiple levels.
First, the article (and paper it's based on) is comparing typical mass transmit commuter planes versus typical car usage with an average of about 1.4 passengers per car. One of the big drivers of increased efficiency in flying is filling planes much closer to capacity, along with making the planes themselves far more efficient by design and by reducing speed slightly. The "flying cars" discussed here seems targeted for single-digit passenger numbers, and the present prototype only has seating for one: the pilot. It's closer to a "flying motorcycle" than a "flying car" (except I'd bet the motorcycle is faster than this).
Second, the comment you're replying to is mentioning the huge efficiency difference between planes and multicopters. Helicopters and multicopters ("rotary wing aircraft") are less efficient than planes ("fixed wing aircraft") because they travel more slowly while still needing to generate continuous lift, and they are less aerodynamic than planes. The article you're citing is discussing efficiency in planes, not heli-/multi-copters.
It really isn't as easy. I'm not saying using an Aeropress is hard. I own one myself and I think it's a great product. But if we use a car analogy an Aeropress is like a manual transmission, and a Keurig is like an automatic. It's not hard to see why people would be attracted to that ease - especially early in the morning before they've had coffee.
I decided to do a bit of searching, and found this detailed article which has some photos of the contents inside the pouches:
http://www.businessinsider.com...
So it contains "chopped" vegetables, but it's actually already pretty finely shredded for the greens. It looks like the fruit chunks are a bit bigger in size. So this is not fully juiced, but it's about halfway there.
The bags are not filled with juice, they are filled with pre-chopped fruit and/or vegetable pieces. Or at least that's the idea behind the bags. I have a little difficulty believing that you could hand squeeze vegetables as effectively as a machine, but fruit should be easy enough.
But at $5-8 per bag, a $400 machine or one to two minutes of hand squeezing I don't really find this compelling. I'm sure the juice is delicious but it costs more than I spend on my whole lunch.