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Comment Re:Use that low pressure air (Score 1) 59

Inductrac is less efficient than air bearings and the track is more complicated to build than straight pipe. That said, if the air bearing concept proved unworkable, I'd think it a fine fallback alternative.

The costs of the turbomachinery on the current design is factored into the budgeting. And you need it either way unless you're planning to run a hard vacuum, since otherwise the vehicle will compress the column of air ahead of it. Industrial air compressors aren't exactly new technology, although the operating environment is admittedly a bit unusual ;) But I do have to agree with their choice of focusing on air bearings. They're simple, light, equal or greater efficiency in comparison to magnetic, and most importantly they keep the "track" simple. The main downside is that they require a fairly high wall smoothness (hence Hyperloop Alpha's need for a rotary tube polisher).

Comment Re:Terrorist target? (Score 1) 59

If you're going to detonate bombs large enough to take out a concrete column for a big steel pipe, why wouldn't you do it where you'd kill a lot more people rather than "hopefully lucking into causing enough deflection (by increasing the span) right before the next capsule arrives that it can't decelerate sufficiently in time to handle said deflection, and possibly killing or injuring one capsule's worth of people"?

Airplane attacks were popular because of the ability to kill hundreds of people at once, or to hijack planes and use them as weapons. Not exactly applicable to Hyperloop. And even airplane attacks seem to be falling out of popularity, in favour of coordinated shootings and plowing through crowds.

Comment Re:Hornby set? Maglev is "new"? (Score 1) 59

If you think the pressure maintenance figures in the Hyperloop Alpha document are unreasonable, cite the actual numbers you disagree with and explain why.

The main advantages over air travel are that the pressure is much lower, frontal area much lower, allowable spacings far closer (no "air traffic"), no noise pollution, no air pollution, and efficient, direct acceleration of the vehicles, with the tube itself serving as a mounting point for the solar panels that power it.

You clearly have never read the Hyperloop Alpha design document. It does include diversion options. There are regularly spaced emergency exits across the track. Vehicles brake to a stop then roll on wheels to the nearest emergency exit.

As for security: the cars are about the size of monorail cars. So if you're going to assert random things about what security will be like, why not assert it'll be like monorail security?

Yes, the design fundamentally does not work if it's not driverless (you really should read the design document before discussing it).

The costs of tunneling are included in the budgeting in the design document (again, you really should read it). There is no "50km long 7,6m diameter undersea tunnel" leg to it.

Comment Re:Think of why maglev is expensive... (Score 1) 59

Why are you under the impression that putting it in a tube makes handling turbing forces, stopping forces and control more difficult? Inside a tube, all motion is perfectly constrained, and you have a tremendous amount of surface area to magnetic brake against.

The turning radii issues are of course real, and are highly addressed in the Hyperloop Alpha document. Likewise for dimensional precision. For smoothness, their solution is a radial polisher which drives down the tube behind the pipelaying crew and smoothing out each orbital weld (and the pipe itself). For straightness, alignment is maintained by the same suspension/alignment system they use to deal with earthquakes.

As for why maglev trains are expensive - trains are expensive for a wide variety of reasons. Land acquisition and permitting is often the most expensive. Tunnels and viaducts are often a very large component as well. Maglev technology itself often tends to have high bills.

Hyperloop (as per Hyperloop Alpha, not the student competition) isn't maglev, it's an air bearing system. Skis, basically. The pipe is built the same as oil pipeline, and the budget is similar to that of oil pipeline budgeting per unit area per unit distance (oil pipelines have harder environmental issues to overcome and much higher loadings, more significant temperature management issues, etc, but lower precision / straightness requirements, so it's probably a wash). Tunnel cost is minimized by minimizing tube size (the budgeted tunnels are standard rates for tunneled pipe in non-urban areas). Viaduct costs are minimized by a key design feature of Hyperloop - minimizing peak loadings by having frequent, small vehicle launches rather than infrequent, large vehicle launches. Viaduct costs tend to track their peak loading.

As for land acquisition, the costs in Hyperloop Alpha are kept down by a combination of design and cheating. As per design, it's designed to be small enough to fit elevated into highway medians, with the low peak loadings, making overhead suspension an affordable option. Such places are state land, and already permitted for far more environmentally harmful activity (road traffic). This of course requires state buy-in to the concept, but states often specifically pursue high speed transport options. Private land acquisition is limited to places needed to maximize turning radii, and in-city for stations. The latter is the other place that they cheat - Hyperloop Alpha avoids cities. LA and San Francisco are served by it, according to the design, like airports on the outskirts of town; people have to get connecting legs into town. But that would be an unpopular decision, and you would expect the state to insist on greater accessibility (airports are only out of town because they have to be, not because that's a desirable location). Likewise it bypasses cities en route, unlike HSR. Basically, it's designed as something halfway in-between HSR and air travel (both in terms of service and throughput), but targeting much lower prices, higher speeds, and a lower energy footprint.

In short, it's budget savings vs. HSR are somewhat of a combination of cheating (cutting out a lot of what HSR does) and design (keeping track loadings down, profile small, build in the same manner as an established industry (pipeline), and moving your hardware (capital expense) through the system as quickly as you can.

Comment Re:Distances (Score 1) 59


Part of the whole point of Hyperloop is that the low pressures aren't extreme (it's not a hard vacuum), and are thus easier to maintain with a regular series of vacuum pumps. And it has no "joints" (the only interruptions being periodic emergency exits, and the pumps themselves). All of the pipe segments are orbital welded and then polished smooth.

Comment Re:Use that low pressure air (Score 1) 59

Wheels at low speed, not maglev.

Of course, the "Hyperloop competition" blurred the line as to what counts as "hyperloop" anymore, because it was based around a bunch of purely maglev options that were radically different from the Hyperloop Alpha design (in many ways beyond just the levitation means).

Comment Jobs have been returning to the US for a while (Score 5, Insightful) 289

Trump or not, it's sure good to see at least some jobs moving in the other direction for once.

According to the Reshoring Initiative, about 41,000 jobs have been returning to the US per year for the last six years. This does not even count jobs that were planned to leave but reconsidered (like Carrier) or jobs created from foreign investment (like FoxConn).

As automation becomes more capable and wages in other countries increase, it just makes sense that jobs would start to return. Unfortunately for the rust belt the jobs which return are often not the same low skill work which was off-shored over the past few decades.

Comment Re:I don't even like Uber but (Score 1) 597

It seems like what you are saying is "some jobs aren't meant to pay for someone's subsistence" My question is "what jobs are those?"

No jobs are meant to pay for someone's subsistence. Jobs are meant to fill a need of the employer. The wages are meant to provide the incentive for the need to be filled. The amount of money it takes to live a good life is completely decoupled from this arrangement. When I need a babysitter, I don't care if my wages are enough to feed and house a 15 year old girl. I only care what amount of money it will take to get the more responsible teenagers in the area to consistently disrupt their weekend plans to watch my kids for me instead.

This is why I greatly prefer a universal basic income, because it allows society to decide what quality of life everyone "deserves" regardless of their economic value. If funded in a progressive way, it doesn't lower the purchasing power of the working/middle class as much as minimum wage and doesn't disincentive economic activity which is not worth the minimum wage.

Are they "unskilled" jobs? If so, are you suggesting that there needs to remain a majority of people without proper education in order to have an "unskilled" work force so that you can go to the grocery store on Sunday or out to eat in the evening?

Unskilled really just means less skilled. Just being literate would have been considered skilled labor 200 years ago, so being "unskilled" is always a moving goalpost. Being unskilled generally means you don't have any skills which would take more than a few weeks / months to teach your average high school graduate. Just like with a business, if your skills don't create a barrier to entry for competing workers, you will probably not command a high wage. The higher the barrier to entry, whether through natural ability or training, the higher wage you will command.

What happens if everybody has an education and is competing on the same level for "skilled" jobs and nobody wants to do the "unskilled" jobs? What happens if we don't have anyone to man the register or pick your food from a field? Wouldn't you say those jobs are necessary?

If for instance the goalpost moves by every person receiving a college-level education, skilled labor will be those who have skills which cannot be quickly taught to your average college graduate (as opposed to an average high school graduate). Someone who did poorly in college and never differentiated themselves would be considered unskilled.

It seems to me that "unskilled" workers are necessary in order to provide a quality of life for the workers in "skilled" jobs.

Yes, we will continue to need many unskilled workers but as I've said there will probably never be a shortage of them since it is a relative term.

Comment Re:As a tech worker with kids... (Score 1) 378

Austin is having the same problem.
Families that have lived there for generations can't afford to anymore.

Yeah I guess everything is relative. As a resident of the Chicago suburbs, when I see a non-foreclosure 3000 sq ft home in the middle of Austin for $400k it seems like the house is being given away. But to many native residents just the $9k in yearly taxes can be enough to cause problems.

Comment Re:As a tech worker with kids... (Score 1) 378

What qualifies as a "park" or "forest preserve" in and around San Francisco is laughable, at best. Come to Muir Woods where you can share 3 acres of forest with eleventy billion other city residents thinking they are getting in touch with their natural side, too!

Muir Woods is more like 554 acres, and sees only 6000 people per day during peak times. Far more than 3 acres and far less than eleventy billion visitors to share it with. And Muir Woods is only part of the Golden Gate National Recreation Area which protects over 80,000 acres of land. This doesn't even count the numerous large parks within the city, like the Golden Gate Park, Presidio, and Land's End. Or the smaller neighborhood parks like Lafayette or Alta Plaza.

I have more forest in my back yard in Minnesota than pretty much all of NorCal combined.

Look up the concept of diminishing returns. Unless you are a real outdoorsy type, you're not going to need much more forest than even a small forest preserve to get a bit of nature in your life. But yes, those types of people are unlikely to like living in most cities. Perhaps the Denver area is one that gives both a modern city feel and easy access to a huge amount of wilderness.

Comment Not good enough! (Score 3, Funny) 276

I want him to roll in the additions from Cilk++, Aspect-Oriented C++ and FeatureC++, the mobility and personalisation capabilities of Occam Pi, the networking extensions provided by rtnet and GridRPC, full encryption and error correction code facilities, everything in Boost, and a pointless subset of features from PL/1.

If you're going to do it all, might as well do it in style.

Seriously, though, Aspects would be nice.

Comment Re:As a tech worker with kids... (Score 2) 378

> The same is true of most desirable suburbs

Yup, exactly, that's why my neighbors are eating a 2 hour commute to the bay area. San Francisco, however, isn't a suburb.

The same is true for the desirable areas in any city. The problem with San Francisco is if you want to live in places like Pacific Heights it costs millions of dollars. In a city like Chicago you can get a decent house in many good neighborhoods for $500k. Go to Texas and it's more like $300k.

Comment Re:Deliberately missing the forest for the trees (Score 3, Insightful) 378

They can't admit that we're in the worst economy for young people since the Depression. They can't get jobs that pay enough for food and housing, let alone a wife and kids.

We are talking about San Francisco, where the economy is booming. The price of housing is skyrocketing precisely because people have more money to pay for housing. The problem has nothing to do with a weak economy.

The problem is caused by zoning. Existing property owners know new construction could lower their existing home values, so building permits are severely restricted. If they allowed more new housing to be built, along with improving public transportation to accommodate greater demand, these problems would diminish.

Comment Re:As a tech worker with kids... (Score 1) 378

Here I am sitting in the 'middle of nowhere' on 20 acres. If the kid wants go go outside, we go out side. Walk on our own property. Go sledding, biking, or what ever else he wants to do. If I need a workout I'll go fell some trees. I can't imagine trying to raise a kid in a concrete jungle.

You do realize there are parks even in cities, right? I only live on a quarter acre of land, but we have a forest preserve and three parks within a mile of our house. The same is true of most desirable suburbs (perhaps not the forest preserves). I significantly prefer public parks to a huge private property for both the community aspect and the lack of maintenance effort.

I grew up on a farm with a nearly 10 acres of non-field/pasture land to maintain, and I sure never want to go back to that. But I can at least imagine why it appeals to others, which you should be able to do about suburb / urban life if you took the time to empathize with other peoples' priorities.

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% APL is a natural extension of assembler language programming; ...and is best for educational purposes. -- A. Perlis