skysight-inc/HackerNews huggingface dataset:
Regular mechanical pumps can haul gas to pressures of a hPa. Any lower, and you're looking at something like turbomolecular pumps. (And efficiency may call for a second stage of specialized mechanical pumps.)

But in my experience, small mechanical leaks are usually of the order of a hPa or so, meaning no high vacuum tech will be needed. Just a fleet of giant blowers and mechanical pumps. (I worked on a wide area sputtering machine for a few years with a few hundred HP of mechanical backing pumps for about a hundred foot long chamber with a 10 sq foot average cross section (order of magnitude error for anonymity ;)) The machine would haul down to 10 or 1 hPa with leaks you could _hear_.

So yeah, it could work practically, especially if it's a welded system and not a giant mess of bolts and o-rings.
“The man who moved a mountain was the one who began carrying away small stones.” -Chinese Proverb

I've lived in China for over 3 years, and spend countless hours riding the HSR system. HSR combines the speed of a plane, with the cost and convenience of a regular bus. Traveling through the countryside of China at 380km/h made me feel like I was in the future. Coming home and seeing the the sad state of our infrastructure was a harsh reality check.

Granted China has a massive manufacturing/mining complex and cheap labor. But if we hadn't squandered 5 Trillion on "War on Terror" and domestic spying, I'm sure we could kept our lead in infrastructure and still has some left over to boost education / R&D spending.

In the past 20 years China's moved their mountain. Hopefully the hyperloop will help us to catch up.
I see just a little bit of hand-waving with how to deal with the 300 psi and 1000 degree F air.

He says they will cool it with on-board water and storing the steam (I don't see a pressure here)in the vehicle. Given the tight space, will any kind of thermal insulation breakthrough be needed?
You're missing the "US citizen" part of what I said.

> Do you have evidence that indicates US citizens are being 'snatched' from the streets of the US without being arrested, tried, or convicted as per the US criminal justice system?

Is what I asked. Non-US citizens aren't necessarily granted the same rights US citizens are granted.
Well, you would no longer need to evacuate the tube...
One may argue then that an ISP could offer a service that bans the Bittorrent protocol under the argument that they want to prevent abuse of an otherwise unlimited connection for only $70/month to connect to a filesharing website that saturates the connection 24/7/365.

In fact, that's basically what started the entire Net Neutrality debate. Comcast got busted messing with the bittorrent protocol, got slapped by the FCC for it, but then got the rules overturned in court. These new rules replace the old principles.

And the new rules are clear: if you are selling broadband, you allow any legal service, application or device.

If something is messing with the network, deal with indvidual user on a protocol-independent basis. If a kind of protocol is congesting the network, like say streaming video, then you may throttle ALL kinds of streaming video, inlcuding your own.

Simple principles that Google used to believe in.

And Google doesn't get to ignore the rules and escape criticism just because Google Fiber is cool. Principles matter.
You can already get the same effect by having a private investor agree to "pay back" the Government if there are really private investors who want to do that.

It's called a "public-private partnership" and it's not completely impossible but it does require some person or persons to cough up the cash.
The tubes for the passenger-only version would be 20 to 23 mm in thickness. I'm not sure what damage a medium-sized gun would do to steel that thick.
We'll need a replacement for all the pleebs to use.
Plus Airtravle could be made 10x better without all that usless security shit. I fligh often from Switzerland to Germany and most of my time is spend standing in one line or another on the airport.

I see no reason that boarding a plane cant be as efficent or almost as efficent as getting on a train.
> something like this has never been built before

That was true of everything, once.
> could CHSRA just build this?

No.

> I understand they're in the planning stages, and I don't think it'd be absurd to say "this is a train, just better and cheaper".

This is a hypothetical concept, while HSR is a widely demonstrated, well-established technology, with real vendors with proven situations. There's a lot of civil engineering to go into building the infrastructure, but the technology is there (and isn't still looking forward to "[s]ub-scale testing based on a further optimized design to demonstrate the physics", as is the case with hyperloop.)

Hyperloop as an alternative to HSR is about in the same situation as nuclear fusion as an alternative to wind (or nuclear fission) power. .
Elon Musk Reveals Hyperloop Concept
> For example, you can put railway tracks up on pylons, too, with very little impact on the ground.

Out of curiosity (I'm not at all familiar with HSR)—does the Hyperloop plan increase the distance between columns or the cost to build the columns (due to materials or any other factors)?
I was disappointed to see that they limit the password length to 30 characters. Perhaps one of the exercises should be to hash passwords that are longer than 30 characters.

Bcrypt will support up to 72 characters. If you are going to limit the password length I'd expect it to be something closer to 72 than to 30.
Although it was effectively the case before, since 2008 PDF is an open format. It's quite misleading to compare it to a binary for which source is unavailable. Since the format specifies compression, not every part of a PDF file may be easily observed in a text editor, but there's a bunch of open software that can read (and edit, and produce) PDF.
Xbox One will still function, even without Kinect plugged in
The NSA is not the DoD, so yes, it'd make sense to ignore that fact.
The total cost of the Hyperloop passenger transportation system as outlined is less than $6 billion USD (Table 8). The passenger plus vehicle version of Hyperloop is including both passenger and cargo capsules and the total cost is outlined as $7.5 billion USD (Table 9).

Love the idea but the cost projections here seem extremely optimistic.
It's in a big, steel tube. You won't see bus-sized things going at nearly the speed of sound; you'll see a big, steel tube.
Probably regulations. They have to maintain integrity in collisions. I don't know if they have to take into account having very heavy freight trains on the same tracks as well.
The creator of this is David Mellis, who is one of the creators of the Arduino project. Apparently he's now in Leah Buechley's group at the Media Lab, which does some great work:
http://hlt.media.mit.edu

This is fantastic, and I'm excited to see what more David will be working on in the future; his dissertation will be an interesting one :)
According to Facebook[1], they exist to "give people the power to share and make the world more open and connected."

I think it is arguable that Facebook has improved the human condition based upon anecdotal evidence of it mostly being positively regarded in our culture for exactly the mission statement above.

Whether we personally agree or disagree with this, right now, most of the world's population still seems to believe that Facebook is a net positive, and I would argue that even if people turned away from Facebook, it would still be positively regarded with some nostalgia by the majority of its members after its obsolescence.

Perhaps Facebook has strayed from that optimistic (and potentially naïve) goal, but in its infancy it didn't even have advertising, then had shitty banner ads, then had a pretty bad ad product, etc. Now they have a decent ad product. That is not very indicative of some type of pervasive corporate culture that exists to serve advertising.

[1] https://www.facebook.com/facebook/info
I'm not from the area, so I don't know how such a ballot works but for voters who didn't have Musk-level engineering knowledge, was the choice the status quo of not fast trains and spending on fast trains?
Ehh, really you don't just speed up the lift you redesign the whole loading and unloading system to allow it to load and unload more people per second. You see this in actual high speed lifts.
Seems like this would be particularly vulnerable to terrorist attacks. There is a huge surface area that needs to be protected (tubes/pylons). If there are pods leaving every thirty seconds and traveling at supersonic speeds then taking out one pylon could kill several hundred people and leave the entire train inoperable. In a future where this design was used extensively to connect cities on the coasts it would quickly become a critical piece of transportation infrastructure. Attacking several arcs of the city graph simultaneously would be utterly debilitating. Especially if the system's relative efficiency leads to the displacement of other forms of transportation.
Doesn't mean building the first one should be expected to be easy.
That's exactly why I said it wasn't "juvenile" ;)
Adding a compressor fan to actively transfer air from the front to the rear of the pod while simultaneously serving as an air cushion to support the vehicle is simple, elegant and absolutely brilliant!

An ingenious solution appears so obvious in hindsight that it leads you to ask "why didn't I think of that?" While being subtle enough to confound all those who came before.

I have been following the developments of the ET3 Consortium for the past year. I have read virtually all the technical literature available online on the topic of alternative high-speed transportation systems going back as far as the RAND paper and even reading related patents from much earlier.

Looking at the genius of Elon Musk's insight is both inspiring ang greatly humbling - but mostly inspiring. Holy awesome! I would love to see this innovation take root. It could be the perfect elixer to our stagnant economic malaise.

Well done Mr. Musk!
The output of the compressor is at 1000 deg. F and 300 psi. That is pretty scary.
And 30 minutes would mean that you could go to Vegas on a Friday or Saturday night and return to crash in your own place.
If a company owns cash, and you own a percentage of that company, it is not really different from owning a percentage of that cash.

The rest of the company still has the same value, plus some (unclear) amount from having successfully raised money.
So who's starting the Kickstarter campaign?
Me, too. When I figured it out I felt silly. Maybe emphasize the construction area and deemphasize the preview? Could the preview be static, and to the right of the construction area and palettes?
Cool ... this gives me hope for the future I want.

The day will come when we will all hold cell phone shaped PCs. You'll be able to interact with them as you do now. However, when placed within 10 feet of a keyboard or mouse, they'll automatically (configurable) and wirelessly use those peripherals ... keyboard and monitors on the fly baby!

Imagine optional super thin foldable displays to pack in the bag ... keyboards too ... or, go big and use production color accurate displays like my NEC 2490WUXi2. Thus making our own like this seems appropriate.
This is also disgusting. Can you imagine a Greyhound where every seat was also a toilet? I would definitely think long and hard before riding it.
This question gets repeated a lot. Here's my answer from a year ago: https://news.ycombinator.com/item?id=4471030

--Copy/paste---

Here's what i did to build http://www.cloudshuffle.com from a single dev(me) to a team of over 6 devs(+ a designer) in various countries. Also, from building social network clones(for $200) to building proper webapps for well known startups and companies like Compete, Hubspot.

* Sign up for all freelancer Marketplaces: Elance, Odesk, Guru, Freelancer, RentACoder.

* Sign up for RSS feeds for jobs(full time/freelance) in your domain.

* Start bidding, sending out emails to all of the above that apply.

* You're bidding against devs from 3rd world countries(so you will have to price somewhere in the median atleast until you get your first decent folio piece done)

* Also it doesn't matter if your request doesn't exactly apply. Don't be self-selective. Also even if you don't expect to get that job, apply still. Get your name out.

* Be very communicative, friendly and more open than a simple 'Here's my folio' etc. You're trying to sell yourself, so figure out what the client want, customize your pitch. This part will take a bit of hit and trial on your end to figure out how to get the first client reply. If your post looks like others, then you won't get one.

* Work on the side on your own project, something that's production worthy and you can showcase if the above steps haven't worked till then.

* Reply to posts on HN, Ask HN like Who's hiring + Who's hiring a freelancer. Even add yourself to HN contractor list and anything similar you see elswhere.

* Market, Market, Market every chance you get. I used to spend atleast 3-4 hrs initially just sifting through job posts, replying, emailing everyday.

* Remember to raise your prices sooner than you think.

* Recently i've been trying out Google adwords, which haven't really led to a lot of hits. But i've been getting like 1 really good query for like 100 clicks. For the average amount i make per invoice, that ad costs are very minor even at the ridiculous CPCs to hit the front page.

* A lot of people mention word-of-mouth here. This is really the best way. For every satisfied client you're essentially expanding your network exponentially and getting in touch with people you would never have come across. But initially since you might not have a portfolio, it will be difficult to get work this way. Also until you're able to price your work higher than average, you won't get the right kind of clients. And without the right clients you won't get paid higher. So it's a vicious cycle you need to get out of by piling up showcase work as soon as possible.

* With lower rates it will be difficult to sustain work, since you would have to take on more work before the current one is over. Hence your focus suffers and work quality too. So you're hampering your prices, word-of-mouth network further if you take on work and underdeliver. I've been guilty of doing this(probably still am).

* So as soon as you get too much work to handle, double your rates.

PS: I'm one of the third world dev that people on HN are very fond of :-)
WAN redundancy - how does it impact VOIP?
Curves are also specced for 0.5g. That will account for quite a bit more of the total acceleration time than just speeding up and slowing down.
> I'd argue that they're largely ignorant of what it means to grant something like Facebook access to your phone (contacts etc).

Being ignorant of how information you've divulged to people is used, does not make that information private.
I hope you're right, but in reality most people haven't even heard of Elon Musk. I've had to explain to many highly educated people what he has done, what SpaceX is, what Tesla is etc. While he's been rather successful so far, he's not in the clear when it comes to either of his companies right now, he's not exactly at the Gates level of success yet. I'm rooting for him though, he has the potential to be one of the most influential people in a long time if things go well.
Introducing Daala part 3: Time/Frequency Resolution Switching
I've just posted part 3 in my demo series introducing the Daala video codec. This one is kind of a long one, mainly because I think it's one of the only really detailed presentations of 'TF' aka Time/Frequency resolution switching.

Not to mention, there's hot glue and saltines.
Sonic car hops make $2.25/hr just like waiters, difference being they are almost always reimbursed to min wage since nobody tips.
"I see no fundamental reason to assume that the hyperloop is lighter than the train."

Did you actually read the PDF?

It doesn't carry its motor with it. That's a pretty big reason. Nor does it need the heavy-duty (and heavy!) trucks of a standard rail car.
Is a Harvard MBA worth it for an Entrepreneur? - Making negative NPV decisions
I can't wait to get the SDK and start developing apps for this.
Each 30M long tube expands 15mm over 40C of temperature change. You could imagine a 15mm expansion joint at each connection, which is roughly what oil/gas pipelines do, but the paper explicitly says tubes will be welded together for straightness.
> I just don't see many governments supporting competing projects. So if CA HSR gets built competing projects, such as Hyperloop, are unlikely to get the required government support.

Given how long it takes to build large scale infrastructure, and given that Hyperloop is still at a primitive stage as technology (the fact that the paper just released calls, as a next step, for reduced-scale testing to demonstrate the physics, whereas HSR is a widely-used, well-established technology with multiple vendors), its more of a long-term successor to HSR than a concurrent competitor.

OTOH, its true that HSR being built would reduce the problems that provide the incentives to build Hyperloop.
Yes to point 1.

I did Toastmasters for about a year and it had a huge impact. They have a systematic way of developing your skills (a set of 10 speeches designed to focus on various aspects, like structure, vocal presentation, gestures, etc...) It seems quite sound, pedagogically.

Now, you do have to have a minimum of tolerance for getting up and doing a first speech in the very beginning, but if you can do that, the rest of the program ramps up gradually. As an introvert, I was never thrilled to be going in to a Toastmasters meeting, but I always felt really good (energized, happy) going out.
I wonder if that $70 billion price tag is partly tied to the "I created x many jobs in my time as a politician" rhetoric. I'm just assuming high cost means a higher number of people being paid.
"I've got a hyperloop to catch."
NY regulator issue subpoenas to firms tied to Bitcoin
http://www.paulgraham.com/hiresfund.html
How does one maintain oxygen ratios?
Putting the railway or tubes on pylons would give you an opportunity to dampen or otherwise transform those vibrations wouldn't they?

Maybe, maybe not. Guideway supports (pylons) are typically founded into the bedrock which does reduce vibration somewhat, but the vertical motion of the pylon moving against the soil will still generate shear waves.

This is why a demonstration project would be useful.
The technical challenges posed by that design seem quite significant compared to those of TFA.
Well, no. You just made that up. HSR is intended to meet a future need for transportation. The equivalent air transportation infrastructure to meet the same need is believed to cost at least $500bn, according to the environmental impact report. That's making the generous assumptions that this level of air travel is even possible without serious air traffic congestion problems, and the aviation fuel costs do not rise faster than general inflation.

The main cost of CAHSR will be the opportunity cost of not having built it.
The problem is that, at least with the CA high speed rail system, the design is all theoretical at the moment. It may be a brilliant idea, but but moving from the core ideas in the document to actual working, build-able products, can be a slow process. And given the state of where CA is on their project, that may not put them on the same window.
I use iOS, and don't use Facebook, but you can't selectively disallow Facebook access to things like the address book? It's all or nothing?
Title is sensationalist and the article is melodramatic.

In terms of threat-level to privacy, this isn't all that egregious. The term "shadow profile" is not one that Facebook itself espouses, it's just added for flair. Clearly, this is making a lot of noise about something that's actually fairly harmless.

I would place more blame on the people sharing my data with Facebook than I would blame Facebook for "mapping" interpersonal data. It's really not that big a deal people.
All your questions can be answered in the Transparent Term Sheet from Founders Fund: http://foundersfund.com/termsheet

It has a calculator that provides economic breakdowns and a supporting article defining the key terms of a term sheet.
Thanks–I think it was the fact that the pylons could presumably be scaled that was making the sentence difficult to parse (I wasn't sure how they were meant to prevent access). That, and that the pylons themselves are also presumably "critical elements" of the system.
The money buys new shares in the company. Think about it in per share terms. In your example:

- Pre-money there are 1,000 shares, valued at $1,000 each

- The company sells 100 new shares for $1,000 each

- Post-money there are 1,100 shares

So after selling 100 shares, the original owner now owns 1,000/1,100 shares = 90.9%. The new valuation is 1,100 shares * $1,000/share = $1,100,000.
For the same reason that Musk needed a huge, free government loan to get Tesla off the ground: without the government, he'd be less rich.
Interesting quote:

The intent of this document has been to create a new open source form of
transportation that could revolutionize travel. The authors welcome feedback
and will incorporate it into future revisions of the Hyperloop project,
following other open source models such as Linux.
I'm happy to scan through the bill of material, I was curious about what price point could be a headless cellular widget for bike tagging.
Indeed, I started getting giddy when he was discussing how to get the best power factor from the stator of the linear induction motor. It's obvious there's been a lot of thought put into this.

On the other hand even with a recommendation to use something similar to TSA doing something similar to airport security, his response plan to a terrorist attac--, er, a "human related incident" is basically to say that the system will have redundant power and vacuum pumps.

I suppose this isn't his area of expertise and so it's better to say little, but this is the kind of thing people are going to worry about before they board a small tube hurtling at 700 mph while 100 feet above the ground.

For instance, does a HRI impact his plan for rapidly handling luggage pods at all? Just one thing to think about...
As a younger developer, I struggle to imagine our senior developers - who have been doing complicated things for 5-10+ years - ever stoop to a number to quantify their experience. I suppose that senior developers are probably not the target audience, but I would never want a company to expect this, or a score to define my experiences as a developer.

A technical screening can be handled in a ten-minute phone call for free - with the dignity of the applicant intact.
The tube itself also isn't bearing nearly the same load as a train track.
Curing Dopamine Addiction To Stay More Productive
In theory that jquery and that angular file should be sourced
I know very little about Bitcoin or money transmission laws. Unlike other currencies it does not seem to have fundamental dependence on any centralized arbiter, though the practicalities of large exchanges like Mt. Gox seem apparent to me. That lack of dependence on a Fed-like body appears to me like its biggest advantage, above any other potential for anonymous payment and laundering. I'd like to know what exactly is entailed in becoming compliant with money transmitting and laundering regulations and whether Bitcoin in its current form could become effectively compliant. Is that even a meaningful concept, or does the structure of Bitcoin fundamentally preclude coming into effective compliance?
Breaking Down Barriers With Vulnerability
Just FYI, [sic] is used when you're quoting something with a mistake and you wish to indicate that mistake is in the source document, and not added unintentionally.