Video Editing: edit your audio really fast - <AUTHOR> https://www.youtube.com/watch?v=zevU2Bdm0Es <comment><AUTHOR> This is a tutorial for our app, Studio Cinematic, to get you started editing audio with a few clicks.

Is this something you guys are interested in?

<comment><USER2> I made it to 1:48, and it seemed like a basic video editing app up to that point.

A comment on the video, not the app: in the first 30 seconds, give me a fast demo of the best part! Hi, I'm X. You can edit audio incredibly fast with Studio Cinematic. Take this: <audio playing in app> "When I, uh, saw the other people and uh, I didn't know how I would find my friend..." And make this: <audio playing in app> "When I saw the other people, I didn't know how I would find my friend."

Etc.

Also, the audio playing in the background was pretty loud- when you began speaking in the ducking example, the background music didn't seem to duck quickly enough. Good luck!

<comment><AUTHOR> Thanks for letting me know! It's clearly my mistake for linking to a tutorial.

This is a tutorial on my app - it was not meant to be a demo. Long story short, I will soon begin a channel where I will showcase my app, and that will contain exactly what you say: "The what", and then I'll describe "the how".

Thanks again!</comment></comment></comment>


Why Do Programming Languages Succeed? (2014) - <AUTHOR> http://flagxor.com/article/why-do-programming-languages-succeed <comment><USER2> > Some paradigms exemplified by the special languages are arguably unrealized > or aspirational. [...] Haskell's pattern matching and monads end up being > used mostly as a vehicle to embed imperative programs.

Pattern matching has nothing to do with imperative programs and Haskell is not original for having it; it's been around since the 70s in ML. I would also argue that pattern matching has been realized in many popular languages (Scala, Swift, Ocaml, Rust ...)

<comment><USER3> You read it wrong. Him said that in Haskell PM & monads are using for make imperative code, NOT that is the defined trait of haskell, instead: "are arguably unrealized or aspirational"

<comment><USER2> The rest of the article lists Haskell as being original for introducing pattern matching and monads as a new programming paradigm.

<comment><USER3> Oh right. In the "Very special" section list that (Without that it could be a more compelling argument).

Perhaps haskell make it more popular?

</comment></comment></comment></comment><comment><USER4> Because of creaters beard. [http://www.wired.com/2012/06/beard- gallery/](http://www.wired.com/2012/06/beard-gallery/)

</comment><comment><USER5> I'm surprised that Scheme is not mentioned. If you consider it to be just a dialect of Lisp then Lisp+Scheme is probably as popular as some of the languages listed as succeeding for popularity. By my count, the combined Lisp+Scheme language has a 1.42% rating on TIOBE, which makes it more popular than Ada, ActionScript, C*, Lua, R, and others. Also, most of the favorable statements about embedding Lua or Tcl apply to Scheme, which continues to get embedded in plenty of important things.

I guess I just don't get the methodology behind the popularity list.

Also, my bet is that Lisp/Scheme would have been even more popular if there had just been one implementation as opposed to a confusing constellation of standards and different implementations. The language is easy to implement so the implementor:user ratio is too damn high.

<comment><USER6> Agreed, if you're going to list Basic and Pascal because they are easy to implement, then Scheme seems like a no-brainer for inclusion. It probably is the most common language for Baby's First Interpreter.

</comment></comment><comment><USER7> Can anyone define "succeed" in this context? Is it purely popularity? What if a language is inferior but popular?

If a language is effective for its user(s), then is it a "success"?

Is there some minimum number of users that delineates a threshhold for "success/failure"?

What about DSL's that might have a limited number of users?

I like that the author recognized the "success" of shell and C as tied to the "success" of UNIX . But he forgot others, such as sed.

Some my favorite and most powerful languages are not widely used. I have no idea what "succeed" means to others in the context of programming languages, but these languages have "succeeded" for me. They get the job done. Efficiently.

Nothing has surpassed Snobol for pattern matching. (If you are in doubt, post a pattern matching challenge and let's see how the solutions in various languages stack up.)

Meanwhile other implementations of pattern matching have become more popular (=successful?)

Perhaps the word "succeeded" here simply means "succeeded in becoming popular?" If so, then I apologize for the gibberish.

<comment><USER8> > What if a language is inferior but popular

aka web-dev-world. Where the lowest common denominator has more foot-guns than C. Worse, the footgun often won't go off directly when you pull the trigger, but some time later, perhaps when it is aimed at your face.

</comment></comment><comment><USER9> I feel like in this day and age, it's "endorsement of a powerful entity" that goes the most towards making a programming language successful - money to pay developers and reputation to gain mindshare are the two things big companies can do best (of course, other factors still apply).</comment>


Search on after Malaysia Airlines flight vanishes - <AUTHOR> http://www.bbc.co.uk/news/world-asia-26492748 <comment><USER2> Would it have hurt _too_ much to have linked to a real civil aviation news site like the Aviation Herald for your running realtime summary of developments, rather than a generic mass media news site run by non- specialists?

(It's about as useful as linking to the BBC for news of a new OS vulnerability, rather than CERT, or even The Register.)

The (detailed) AvHerald coverage is here: [http://avherald.com/h?article=4710c69b&opt=0](http://avherald.com/h?article=4710c69b&opt=0)

 __Personal observation __: I flew through KUL on Malaysian last year, and was very unimpressed by security: it was cursory in the extreme and if I remember correctly out passports weren 't electronically captured on entry or departure. Reports of someone using a stolen Italian passport being among the passenger manifest are a bit worrying (although some sort of mechanical failure is far more likely than terrorism).

<comment><USER3> There's a submit button up top, use it. Downvoted for unconstructive comment.

<comment><USER4> I thought it was an interesting comment, so, cancelled that out for you. :)

</comment></comment></comment><comment><USER5> The last time I read a news title like this (where they use words like Flight Vanishes) was in 2009 about the Air France Flight 447 from Brazil to France.

I still find this story extremely puzzling for many reasons:

1-Boeing 777 is one of the most technologically advanced and safe planes.

2- Malaysian Airlines are one of the best airline companies in the world.

3- The weather seemed to be clear with no storms or strong wind (unlike the case with the French flight)

4- communication was lost completely with the aircraft. I'm not an airline expert, but shouldn't be there at least a fallback for the communication protocol being used e.g: radio/satellite/GSM etc .. ?

<comment><USER6> I don't know about avionics much either, but I'm wondering why, even at the time of AF447 if the planes do broadcast information about their current position (including altitude and speed), there seems to be no obvious "Your plane is dropping from the sky!" warning generated by any systems and remotely sent. Even if it's not a continuous stream of data, planes don't fall infinitely fast; it took a few minutes for AF447 to reach sea level.

<comment><USER7> The A380 does this. If you watch the Air Crash Investigations episode (also known as "Mayday) Season 13 Episode 10 - it talks about the Qantas A380 that had an engine explosion.

All the data from the plane was being relayed back to Qantas HQ - and the engineers at Qantas HQ were able to see in realtime all the issues facing the plane.

Ironically there were so many issues, they actually initally thought the system was faulty (i.e. there were too many faults, so the fault must be the alert system).

<comment><USER8> That's another case of the automation paradox though, is it not? The engineers are suddenly inundated with all kinds of information and it isn't clear what the actual cause is. When you look at AF447, part of the problem was that the pilots appear to have been unaware that all the errors they were seeing were caused solely by loss of airspeed indicators.

So most of the time you aren't looking at stuff, then suddenly something happens and you get tons of information on what exactly isn't working right now, all of which may or may not be useful in determining what the real problem is. And in this case humans have to step in quickly and react flawlessly based on perfect knowledge of the failure.

</comment></comment></comment></comment><comment><USER6> Governments have developed so much surveillance technology that they can easily invade the privacy of many citizens, yet tracking the exact whereabouts of planes flying in the sky - something that for scheduled, commercial flights whose routes should very much be publicly known information - still seems out of reach? I find that fact a little unsettling.

<comment><USER9> Dude, not cool.

<comment><USER10> I don't see how that's not cool.

<comment><USER11> Presumably sldcool is objecting to using this tragedy to make a political point so soon.

</comment></comment></comment></comment><comment><USER12> I appreciate that radar only works above a certain altitude, but can someone explain to me why a vehicle worth > $200m doesn't have a GPS unit broadcasting over longwave radio,satellite connection or some other remote communication means. I feel like I'm missing something fundamental.

<comment><USER13> All modern aircraft are equipped with Mode-S transponders [1] which broadcast several parameters such as altitude, lat/longitude and aicraft ID info. There are also specific messages that signal "emergency status"[2].

You can 'listen' to these messages yourself with very basic radio equipment tuned to 1090 MHz[3].

Even though these signals can reach long distances (I remember getting ~300 Km with my home made antenna) it's possible that the plane was going through an area where no base stations exist.

[1]: [http://en.wikipedia.org/wiki/Aviation_transponder_interrogat...](http://en.wikipedia.org/wiki/Aviation_transponder_interrogation_modes#Mode_S)

[2]: [http://www.faa.gov/air_traffic/publications/atpubs/aim/aim04...](http://www.faa.gov/air_traffic/publications/atpubs/aim/aim0405.html)

[3]: [http://www.rtl-sdr.com/adsb-aircraft-radar-with-rtl- sdr/](http://www.rtl-sdr.com/adsb-aircraft-radar-with-rtl-sdr/)

<comment><USER14> Those signals are very much dependant on direct line-of-sight. Transmitted from the ground or on the ocean the range would be very low.

<comment><USER13> Sure. I find that I easily lose track of planes if they are below a certain altitude. Still, it is very strange that the last recorded altitude is 35000 ft [1].

[1]: [http://www.flightradar24.com/data/flights/mh370/#2d81a27](http://www.flightradar24.com/data/flights/mh370/#2d81a27)

<comment><USER8> The deviation from planned flight looks odd to me.

On second thought, looking at other flights, it seems not so odd.

<comment><USER15> Deviation from planned flight is very, very common.

<comment><USER8> What looked odd to me at first was not the deviation but the fact that it seemed almost mechanical. As I looked at other flight paths vs actual flights however it became clear that this sort of deviation was relatively common.

</comment></comment></comment></comment></comment></comment></comment><comment><USER16> Apparently an Italian passenger on the passenger list was in fact not on the plane[1] (and did not buy a ticket, passport was stolen), could be another sign for a terrorist background.

For more information/speculation the airliners thread[2] is also a good source.

[1][http://www.corriere.it/esteri/14_marzo_08/scomparso-aereo- di...](http://www.corriere.it/esteri/14_marzo_08/scomparso-aereo-diretto- pechino-bordo-239-persone-anche- italiano-4340534c-a683-11e3-bbe4-676bb1ea55e1.shtml)

[2][http://www.airliners.net/aviation- forums/general_aviation/re...](http://www.airliners.net/aviation- forums/general_aviation/read.main/6013944#menu29)

<comment><USER17> Don't bags that belong to passengers who don't embark get taken off the plane as a standard security measure?

<comment><USER8> What we know is that two apparent passengers were on board with stolen or forged passports. Obviously they meant mischief, since you don't travel internationally on a stolen passport if everything is above board.

But when you think about it the sorts of mischief that could be involved are quite many and varied. One can't rule out terrorism, but it's one possibility among sufficiently many that this is not where I personally would start. Far more likely you are dealing with organized criminals doing more typical organized criminal things (like smuggling stuff).

Additionally usually if the plane is intentionally downed, someone will want to take credit/responsibility. That this hasn't happened is an indication, particularly absent patterns of attacks here in the past, that this is just criminal business as usual and not related to the accident.

Finally there are early unconfirmed reports that the Vietnamese navy may have spotted smoke columns yesterday. if that turns out to be the case, it would be a strong indication that the plane exploded on impact with the water, not in the air.

At present I am so far from being able to endorse the T-word explanation that it doesn't seem worth looking further into at this point.

</comment></comment></comment><comment><USER18> Can't really imagine how are the relatives of all these innocent people feeling.

And also can't imagine that in 2014 we are not really sure where an airplane is..

<comment><USER19> I thought with radar we could track every plane on earth at all times? By bouncing it off the ionosphere or something?

<comment><USER5> I had the same impression as well :

[http://www.flightradar24.com/](http://www.flightradar24.com/)

<comment><USER20> there is a 250-400 km range for FlightRadar, it does not cover oceans very well.

[http://www.flightradar24.com/how-it-works](http://www.flightradar24.com/how- it-works) "Flightradar24 has a network of more than 3,000 ADS-B receivers around the world that receives plane and flight information from aircraft with ADS-B transponders and sends this information to our servers. Due to the high frequency used (1090 MHz) the coverage from each receiver is limited to about 250-400 km (150-250 miles) in all directions depending on location. The farther away from the receiver an aircraft is flying, the higher it must fly to be covered by the receiver. The distance limit makes it very hard to get ADS-B coverage over oceans."

</comment></comment></comment></comment><comment><USER21> Navy confirms plane crashes into the sea: [http://sg.news.yahoo.com/mas- aircraft-goes-missing--says-air...](http://sg.news.yahoo.com/mas-aircraft- goes-missing--says-airline-023820132.html)

<comment><USER22> Not really, no. Immediately after that statement it says "When contacted, Malaysia Airlines declined to confirm or deny the reports", and nor has it been confirmed in the six hours of updates to that story since.

<comment><USER21> You're right: [http://uk.reuters.com/article/2014/03/08/malaysia- airlines-c...](http://uk.reuters.com/article/2014/03/08/malaysia-airlines- crash-wrapup-1-picture- idUKL3N0M508X20140308?feedType=RSS&feedName=rbssFinancialServicesAndRealEstateNews)

</comment></comment></comment><comment><USER23> How difficult is it to scan the entire area using satellites? There are civilian satellites that offer resolutions better than 30cm today, surely enough to spot wreckage in the middle of the sea. DigitalGlobe alone has over 3 active satellites that can scan an area of over 10,000 km^2 in a single pass, and the combined revisit times should be good enough. This should also be possible using SAR with a good enough resolution, as the sea would appear mostly black and anything non-smooth on top of it should stand out.

Edit: made a mistake concerning the area. Fixed now.

<comment><USER24> The area of sea involved quickly works out to tens of thousands of square kilometers.

<comment><USER23> The whole area between Malaysia and Ca Mau is bounded within a square of less than 500 km^2, and even that is a vast exaggeration of where the plane is most likely to be.

<comment><USER24> Either I am completely confused or you are misreading something. The linear distance is more than 300 kilometers. 500 square kilometers is only 22 kilometers on a side. It's a tiny little patch of the sea there.

<comment><USER23> You are right, it's my mistake. I meant 100^2 km^2 (for the satellite coverage), and 500^2 km^2 for the bounding area. Fixed.

</comment></comment></comment></comment></comment><comment><USER13> Here is the flight path of MH370, before it ceased responding to tracking stations:

[http://www.flightradar24.com/data/flights/mh370/#2d81a27](http://www.flightradar24.com/data/flights/mh370/#2d81a27)

35kft altitude.

</comment><comment><USER25> Oil slicks have been spotted in the ocean. [http://bigstory.ap.org/article/china-bound-malaysian-jet- van...](http://bigstory.ap.org/article/china-bound-malaysian-jet- vanishes-239-aboard)

</comment><comment><USER26> How many aircraft are in the air at any one time? Or over a span of 24 hours?

How much bandwidth and storage would it take to collect information about where an airplane is at any point in time?

<comment><USER18> How many cats pictures are currently posted online? How much clouds are being deployed right now?

</comment></comment><comment><USER27> I remember when this happened to Oceanic flight 815.</comment>


Spokeo - <AUTHOR> http://www.spokeo.com

<comment><USER2> I actually paid the fee to see if they could come up with anything else - Given I use _exactly_ the same userid everywhere, and it is extraordinarily rare - I'm shocked at how the poor results are. Had the incorrect address for me, incorrect phone number, and was missing a ton of blogs that i regularly participate in.

If anything, spokeo gives a very, very poor sense of what type of information is collected on you. If only it was so minimal.

</comment><comment><USER3> I don't know about that. If they aggregate the info without breaking into anything I'd call it fair game, however unfortunate. The info is out there, they just make it easier.

</comment><comment><USER4> The title's just been edited. For context, the original title was "Spokeo - The Biggest Privacy Invasion in Internet History".

</comment><comment><USER5> More like the most sensationalist title in internet history.

<comment><USER4> I'm half convinced this is some kind of clever marketing campaign intended to get peoples' attention and make them go to the site where they say "Hey, this isn't so bad" and start using the service.

</comment></comment><comment><AUTHOR> The data I see (from the people I know), is that it seems to pull real estate info, and is incapable of knowing where you've moved (if into a dorm or apartment) after moving out of your parents place. But it seems deadly accurate in giving me the addresses of every single one of my close friends parents - so I imagine those right above me in age (with homes) it would also predict very well.

You can remove yourself in the bottom right.

</comment><comment><USER6> I got this same link and fear mongering from my Aunt. I couldn't resist replying to her to let her know that Intellius and Rapleaf probably have more information on her. Not to mention, if she uses any Google services, that they probably parse her email, Internet searches, and track her web surfing via Google Analytics and AdSense.

Then she told me she had a Droid X.

The funny thing about privacy these days is that it has really become a commodity. We trade our privacy for services, free samples, and products. We're trading something that isn't renewable. Eventually, we'll run out.

If you haven't watched Moxie Marlinspike's talk on Changing Threats To Privacy, I strongly recommend you do:

[http://www.securitytube.net/Changing-Threats-To-Privacy- From...](http://www.securitytube.net/Changing-Threats-To-Privacy-From-TIA-to- Google-%28Blackhat-2010%29-video.aspx)

Also, if you're interested in just how data is out there, check out a tool called Maltego:

<http://www.paterva.com/>

</comment><comment><USER7> How do I remove myself from Spokeo, NOW.

<comment><USER8> <http://www.spokeo.com/privacy>

</comment></comment><comment><USER9> We could not locate 'Cole XXXXXXX'.</comment>


Ask HN: Describe your first internet experience you remember - <AUTHOR> I'm 42, so I was in high schools when the WWW came into my life. I used to devour Popular Mechanics magazine, and one issued noted the magazine had a website. My school library had an internet connection. The next day I rushed to school when the doors were unlocked and bolted to the library. A solo PC sat on a writing desk amidst rose collored carpet and brown wood bookshelves, next to a tall indoor plan (no idea what make and model - it was beige). The PC was magically already booted, as expected (librarians := unsung heros). I somehow identified the internet browser - maybe AOL. I connected (errr.bong.bong... etc.). I typed in the address char-by-char and pressed enter, then in a flash of blazing glory... nothing. I tried again... nothing. Then, I decided to wait and allow things to process, and low and behold a solid scarlet square appears in the upper left corner. I waited with baited breath for, what I would come to learn would be called, for the web page to load. Sadly, that never happened. Despite skipping "homeroom" (ask your North American Scum friends), I could not miss first period and had to break the stand-off. Alas, my first call accross the internet was left painfully unasnwered. I held a grudge for a while, but we eventually madr up. <comment><USER2> Gopher. Archie. There was one where you would email a request, it would email back some resource indentifiers, then you would email back the resource you want and back it came. For when your employer allowed email but not open internet.</comment>


Problem with most of the scholarships out there - <AUTHOR> I have seen people filling fake achievements and details in their Scholarship applications. These Scholarships are the ones that are selected purely based on Application details we fill in. With this vulnerability, right/deserving candidates are often missed the opportunity. <comment><USER2> With my experience of Indian software industry and education system, this is the single-most reason that resulted in deficiencies of Aadhar implementation.

<comment><AUTHOR> Not quite relevant here.</comment></comment>


Olympic kangaroo courts to be introduced in the UK - <AUTHOR> http://www.telegraph.co.uk/sport/olympics/news/9355742/London-2012-Olympics-Offenders-to-face-instant-justice-under-new-court-plans.html

<comment><USER2> Not too sure what leasons from the summer riots there trying to address here. Mostly seems concerned about crime tourists who will of left the country before they can be made to pay for there crime.

Nice idea and good to see videoconferencing being used to save time and travel costs. Shame the RIO mob all had to fly to Rio to discuss the enviroment as apposed to doing it online /o\\.

Not sure if this should and if indeed it will be a simple list of crimes at certain locations that will be acted upon and somebody smoking a cigarrete in a area there not supposed to be near a Olympic logo may fall within that remit. Indeed they could be upwind of a alethelete and in that could be charged with assault and other silly things.

I realy don't see any real problems with this, as long as the appeal process is maintained and fair legal support is afforded the suspect.

Though it does remind me of the start of the TV series Lexx.</comment>


Ask HN: How do you evaluate a stock tender offer? - <AUTHOR> I have to evaluate a tender offer for private stock from a previous employer with a deadline coming up. I have some updated financial statements but have no idea if this is fair or not. On the one hand, it would be smart to diversify since it's decent sum of money in the "SF house money" size. On the other hand, it would suck if the shares were actually worth much more and sold prematurely. <comment><USER2> Sell half. Keeps you in the game if there's big upside while getting some cash now if there's not.

<comment><USER3> I'm not disagreeing, but what's your background/reasoning for this advice, specifically the "50%" part?

<comment><USER4> When I worked in markets I would often get asked questions in the form of: should I short X? Should I trade X currency now or later?

More specifically many questioned whether they should buy GBP/USD the day before brexit or the day after. The only good advice is to buy 50% the day before and 50% the day after, that way you are wrong both times.

</comment></comment></comment><comment><USER5> This is gonna be pretty hard to figure out. I'd recommend you take it to someone knowledgable - a startup accountant or lawyer perhaps; they can give you comparables. For the kind of money you're talking about you should definitely have a lawyer looking over the docs.

I tried writing out some general advice, but there's so many possible scenarios: is the company hot, is growth flat, is it trying to sell to someone (PE firm or later stage investor), why are they even buying your stock?

I agree with ralph84 that selling some smaller number keeps you in the game and also let's you cash out - founders and early employees regularly do this, and they are big believers in future upside. Also remember that even if the stock goes up in the future, you should price in the cost of having that money now (everything from the appreciation of a house you may buy, to factoring in expected value).

Main advice: get a lawyer. If you're looking for someone to talk through the options informally, my email is in my profile.

</comment><comment><USER6> One common approach for valuation is to use comparable companies as a benchmark. This is where you take a similar company's financial statements and compare the relative valuation. The first step is to identify similar companies and do a search for their valuations. Once you have similar companies, you can use ratio like price/earnings to compare them. good luck.

<comment><USER7> More likely the company at this stage is evaluated on earnings growth, not absolute earnings. Or more nebulous, $/user. But it's a way to mentally check whether the valuation is reasonable. Will the earnings growth grow into a stable earnings fit for its market cap? A mature best of breed company (S&P average) gets something like 22 P/E right now, but historically that fluctuates as well based on earnings outlook and interest rates (which are still historically low).

The last point on interest rates is overlooked by casual investors. Interest rates drive valuation, because the risk-free Treasuries rate is the ultimate comparable to other investments. Not only does it cause the P/E of mature companies to blow up as people chase yield, it forces hot money to chase earnings growth as prospective returns get miniscule. It also gives funds massive borrowing power.

Basically, consider the risk of the whole thing blowing up even if the company does not.

The last line sounds scary, and it could be, and if you don't know it's the thing to really consider. Risk versus reward. Selling half seems like a brainless way to make a decision, but the benefit of this is that it actually lets you make a decision (you win psychologically both ways).

Companies do not do stock tenders all that often and it could be a good sign. But it also happens that companies buy during good times when cash is flush.

</comment></comment><comment><USER8> Find a middle ground that won't let you regret your decision. I tried this once and felt pretty good about the results.</comment>


Mercurial 4.0 Sprint Notes - <AUTHOR> https://groups.google.com/forum/#!topic/mozilla.dev.version-control/nh4fITFlEMk <comment><USER2> I know this is slightly tangental but I'm always a little shocked that Facebook (and I think Google to some extent) have massive mono repositories.

The benefits of having one repository do not seem to be worth the serious performance issues as well as potential coupling that can happen with a gigantic code base as well also making much more difficult to OSS certain parts.

e.g. why doesn't FB use dependency management (or binary package management aka maven, npm, etc)? That is have multiple repositories and cut releases. Build tools to help cut and manage the releases and dependency graph of the releases.

There are even plugins and shell scripts that will make Mercurial act like a mono repository for many small repositories (I use it for our own Java Maven code base).

I must be missing some killer features and would love to see it in action (FB major repository).

<comment><USER3> Anyone who is old enough to remember the pain of VCSes like CVS and RCS will note that the number one feature touted to move to any other VCS is invariably "atomic changesets"\--all the necessary changes to files are listed in a single changeset. Monorepos are nothing less than remembering the value of those atomic changesets.

An example of utility of monorepos is things like automation--if you change, for example, how you publish packages, and you need to maintain multiple stable branches, it is immensely useful to keep the automation steps in the same repository as code. If you don't, your automation repository then looks like

        if version < 31:
            step_a()
            step_b()
            step_c()
        elif version < 35:
            step_a()
            step_bv2()
            step_d()
        else:
            ...

which quickly grows unmaintainable at scale.

<comment><USER4> I can only imagine that the only way to scale that would to make whoever owns the repo responsible for automation as well. A dedicated team can provide the tooling/frameworks (basically a "golden path") but if/how would need to be up to the team. I think in a general sense this is the approach Netflix takes to services.

That said I have no idea how Netflix does source control, only that they use BitBucket/Stash on-prem and that supports both mercurial and git.

</comment></comment></comment><comment><USER5> I had no idea Google and FB were dabbling with Mercurial.

I checked it out years ago, but pretty much settled on Git.

What are the advantages?

<comment><USER6> 1) The .git directory doesn't play nicely with mono-repos. Since all files are just hashed files that live in the .git dir, knowing which files in there are part of a subtree is hard. On the other side, Mercurial .hg dir uses a tree structure to track files, so you can do things like NarrowHG[0].

2) As well, Git has multiple client implementation (like git, egit, jgit, etc...). Adding new features is a bit more complicated as all the implementations need to add them before they can be more widely used. Mercurial has one implementation that everyone uses. So new features are easier to add.

3) The .git structure is simple, which is great, but it's become the API for git in a way. While mercurial explicitly says you should never rely on the structure of the .hg directory. If you want to interact with the .hg dir from other software, you should either issue 'hg' command or start up a command server[1] to talk with it. So it creates a cleaner API barrier. Because of this, the Mercurial team can make changes to the .hg dir to better serve different needs (like those of a mono-repo), without breaking the world.

[0] [https://bitbucket.org/Google/narrowhg](https://bitbucket.org/Google/narrowhg)

[1] [https://www.mercurial-scm.org/wiki/CommandServer](https://www.mercurial- scm.org/wiki/CommandServer)

<comment><USER7> The .git file format has also changed multiple times, packed refs, multiple pack file formats etc. There's even WIP ref backends now which store the whole thing in some embedded database format.

<comment><USER8> There is no ".git" file. It's a directory with a lot of files. Some of the packing has been storage optimisations but the logical model (objects identified by hash) has remained the same throughout.

The nice thing about this is you can present the same logical model while being flexible about the way that model is persisted, unlike Mercurial which has a fixed file format upon which operations are based.

</comment></comment></comment></comment><comment><USER9> What about speed?

Our team just moved from hg to git for an enormous project that has ~25 years of history (CVS -> SVN -> hg|git). The biggest improvement to my daily life is that a git pull takes seconds, while an hg pull takes minutes (or even large fractions of hours when I've spent a week or two away from work).

<comment><USER10> You don't have much history in git at the moment.

<comment><USER11> Didn't he say he imported a repository with 25 years of history?

</comment></comment></comment><comment><USER12> That was a busy meeting and the developer mailing list is very busy. It's great to see continued investment from so many interested parties.

Judging by the notes in the wiki [1], however, the purveyors of my preferred server, Kiln, are not so engaged lately:

> Available hosting solutions: Bitbucket, Kallithea (self-hosted), Kiln (still > exists?)

I believe it is maintained and even if not maintained would continue to work for ages, but I suspect we will be held to 3.x for a while.

[1]: [https://www.mercurial-scm.org/wiki/4.0sprint](https://www.mercurial- scm.org/wiki/4.0sprint)

<comment><USER13> What's you best KILN feature ? I wonder if we can adopt it at RhodeCode

<comment><USER14> Kilns biggest omission, which is what made me choose Bitbucket, is the lack of branch pull requests. Kilns commit-based PRs are useless in a feature branch workflow.

Bitbuckets code review implementation doesn't handle big changes gracefully though, so I primarily inspect the changes in Beyond Compare.

<comment><USER15> What's hilarious/sad to me is that Kiln started out (as the prototype that won Django Dash) doing _only_ pull requests. That was literally all it did. Pushing directly to a repo would instead, behind-the-scenes, make a branch repo and put your commits _there_. When you accepted the review, it'd automatically get merged. Kiln would even warn you if you could safely do the merge without conflicts. This was all back in 2008, and I believe predated GitHub launching entirely, but certainly predated PRs being common.

Hilariously, we concluded internally that doing things that way was too complicated/weird for people to use, while GitHub concluded the exact opposite, and the rest is what you see.

</comment></comment></comment></comment><comment><USER16> hg absorb sounds very useful. I'd like to know details, since I can imagine undesired results it might produce.

<comment><USER17> Looks like it uses annotate information, seems pretty handy.

[https://bitbucket.org/facebook/hg- experimental/src/default/h...](https://bitbucket.org/facebook/hg- experimental/src/default/hgext3rd/absorb.py)

</comment></comment><comment><USER18> So is this a comeback of Mercurial?

I know Subversion is pretty much dead, Mercurial was sidelined and Git seems to have conquered the world. The only thing I think would shake things up a little would be Perforce going Open Source. But i dont see that happening as they seems to be very comfortable in their niche.

</comment><comment><USER19> anyone knows if mercurial subrepo feature is used by big corporations

</comment><comment><AUTHOR> Relevant quote:

      > Facebook is writing a Mercurial server in Rust. It will be distributed and
      > will support pluggable key-value stores for storage (meaning that we could
      > move hg.mozilla.org to be backed by Amazon S3 or some such). The primary
      > author also has aspirations for supporting the Git wire protocol on the
      > server and enabling sub-directories to be git cloned independently of a
      > large repo. This means you could use Mercurial to back your monorepo while
      > still providing the illusion of multiple "sub-repos" to Mercurial or Git
      > clients. The author is also interested in things like GraphQL to query repo
      > data. Facebook engineers are crazy... in a good way.

<comment><USER20> A suggestion if I may... Don't use monospaced formatting (two-space prefix) as a way to put a '>' on every line of a long quote, as it becomes unreadable on mobile. One '>' at the beginning of each paragraph is good enough (with blank lines to separate paragraphs), or italics are fine too.

Here's a copy that should be readable on any device:

> Facebook is writing a Mercurial server in Rust. It will be distributed and > will support pluggable key-value stores for storage (meaning that we could > move hg.mozilla.org to be backed by Amazon S3 or some such). The primary > author also has aspirations for supporting the Git wire protocol on the > server and enabling sub-directories to be git cloned independently of a > large repo. This means you could use Mercurial to back your monorepo while > still providing the illusion of multiple "sub-repos" to Mercurial or Git > clients. The author is also interested in things like GraphQL to query repo > data. Facebook engineers are crazy... in a good way.

<comment><AUTHOR> This is offtopic so I'll leave it to just this one reply, but thanks! Lack of quoting in HN's markdown is the only part I have actual frustration with it; I usually use the two-space + wrap format because it makes it much more clear that it's a quote; I find your version hard to tell. But that said, I checked on my phone, and I see what you're saying about mobile. Ugh.

<comment><USER21> HN markdown _does support italics_ , so italicizing entire paragraphs is a viable alternative to differentiate what you're quoting from your own comments. I've seen folks do it now & then.</comment></comment></comment></comment>


Paul Buchheit: The first thing that you need to understand about humans - <AUTHOR> http://paulbuchheit.blogspot.com/2007/08/first-thing-that-you-need-to-understand.html <comment><USER2> I'm surprised someone like Paul Buchheit only realised this several years ago!

This is the reason I allow myself full latitude in arguing with people, including the freedom to change my mind completely from one argument to the next. After all, whatever your opinion is right now, it's only the best you've come up with so far - a better, truer truth may be just around the corner. This unsettles some people, when they hear my passionately arguing a point one week, and then passionately arguing the opposite point the next week.

This is also why I make a conscious effort to allow opposing viewpoints to exist in my head. After all, both might be true - even together. Just because I've rationalised them to be opposing doesn't mean they're not both true.

An interesting point that's not made in the article is how to train this rationalisation engine. It's a very powerful tool, that brain of ours, and I believe there are ways to feed our subconscious with "good data" that it can use for more effective heuristics. I'd argue that reading good books (particularly classics) does a tremendous job of making our subconscious more effective.

<comment><USER3> I knew this before reading the article, but I just can't recall where I got it from. I find it kind of ironic how he provides all this scientific theory as a sort of rationalization of the idea...

</comment></comment><comment><USER4> Somehow this article reminds me of a show on NOVA called "Secrets of the Mind". In one instance, someone had a car accident and been in coma for five weeks.

"V.S. RAMACHANDRAN: He was articulate, he was intelligent, not obviously psychotic or emotionally disturbed. He could read a newspaper. Everything seemed fine except he had one profound delusion. He would look at his mother and he would say, "This woman, Doctor, she looks exactly like my mother but in fact she's not my mother. She's an imposter. She's some other woman pretending to be my mother.

NARRATOR: The injury to David's brain had brought on a very rare condition called the Capgras Delusion"

...

NARRATOR: Whenever we look at an object or a face, the message reaches the temporal lobes, where it's identified, but then it gets relayed to a structure called the "amygdala," which is the gateway to the limbic system that contains the emotional centers of the brain. And it's here that we generate the appropriate emotional response to whatever it is we're looking at.

V.S. RAMACHANDRAN: Now, what I've suggested is that what's going on in this patient is the message gets to the temporal lobe cortex, so the patient recognizes his mother as being his mother and evokes the appropriate memories. But the message doesn't get to the amygdala, because the fibers going from the temporal cortex to the amygdala into the emotional centers are cut, as a result of the accident. Therefore, there is no emotion. There is no warmth. And he says, "If this is really my mother why is it I'm not experiencing any emotions? There's something not quite right here. Maybe she is some other strange woman pretending to be my mother."

<http://www.pbs.org/wgbh/nova/transcripts/2812mind.html>

<comment><USER5> Dr. Ramachandran relates this case (capgras syndrome) in his TED talk as well. <http://www.ted.com/index.php/talks/view/id/184>

</comment></comment><comment><USER6> Humans are born rational, but we teach ourselves and others to loose our rationality through cultures, civilization and traditions.

Conduct the "umbrella" experiment with a child about 3-5 years old. His answer will be " I do not know". Honest, right?

As kids we always expressed our feelings and thoughts properly and truthfully through words and actions. But, somewhere between the age of 4 and 9 we start to have others think for us. We are thought sets of realities that mostly make no sense to us (as children).

By the time we reach 13 we already have all this new man made reality that we are supposed to live and think by without much questioning.

So this creates a massive database of words and actions we go to first to express our thoughts and feelings.

By doing this we ignore our highest truth. We create a conflict between what we put our there and what we really feel and know inside. There begins the war within ourselves.

We almost cannot reverse engineer in months what we have created in millenniums. I do not think this mass change in the way we think is going to happen in our lifetime.

But we can stop stopping our kids to think for themselves. Stop giving them sets of realities that are contradictory to their real honest and pure feelings and thoughts. You would think this would create an anarchy, but we will land far from that.

<comment><USER7> I get asked about my motives for my actions, probably about as often as everyone else gets asked. I've never been sure; the questioner has invariably regarded this as a sign of dishonesty on my part, while I've thought it to be a failure of introspection. Good to hear I've really just been avoiding the self-deception of conscious rationality.

</comment></comment><comment><USER8> Good salesman have always known that people buy with emotion and justify with logic.

Functional software that perfectly solves a customer's problem without a good user interface never makes it to the logic step. It was eliminated by the user's subconscious before the game ever began.

</comment><comment><USER9> Paul's treatment of marketing brought to mind Gladwell's _What We Can Learn From Spaghetti Sauce_ : <http://www.ted.com/index.php/talks/view/id/20>. The Ockhamist dialectic -- "If we are going to be honest, then we must admit the possibility that everything we know and believe is, in fact, incorrect" -- evokes existentialists e.g. Eckhart Tolle: "The greatest achievement of humanity is not its works of art, science, or technology, but the recognition of its own dysfunction, its own madness."

</comment><comment><USER10> I found what I think is a flaw in the "picking the attractive" examples mentioned in the article - Why exactly is it not rational to pick/vote people based (among other criteria) on their attractiveness? I am not saying I know the answer, but assuming something is not rational, without rational arguments - even if it looks obvious - is exactly what the article wants to criticize. ;-)

<comment><USER11> The article doesn't say that hiring attractive persons is wrong The article says, or at least that's what I understood, that people hired attractive persons not knowing why.

</comment></comment><comment><USER12> Good examples: Alarm clocks with Snooze functions & people smoking cigarettes

<comment><USER13> What's irrational about having a snooze function?

<comment><USER7> An alarm clock's function is to wake you at a specific time. A snooze button's function is to delay that wakening. It's as rational as popping up an "Are You Sure?" dialog box.

<comment><USER13> For people who don't want to get out of bed as soon as the alarm goes off, but who also don't want to risk sleeping for another hour, a snooze button is perfectly sensible.

<comment><USER14> Yeah, but it would be nice to force myself to get out of bed each time the alarm goes off, immediately, and without fail. This is somewhat of a tangent, but I think that when I set a bunch of alarms on my phone (for 9:00, 9:30, 10:00, and 10:30, for example), it's actually harmful because I'm training myself to not wake up immediately. I stand up when the first alarm goes off and think "Man, I am _super_ tired.. My legs are like jelly. Hey, I can sleep for a little while longer since more alarms are set." The result is that I'm usually late for whatever it is I have my alarms set for, since by the last alarm I've already trained myself to just jump back in bed. It's totally illogical.

I'm still 20, so maybe this behavior will diminish with age. But I'll probably try some experiments, like only having one alarm set (with snooze disabled).

<comment><USER15> It sounds a bit strange and it feels a bit strange too, but you can practice getting up when the alarm goes off.

Before you go to sleep, set an alarm like a minute in the future. Lay down, close your eyes, relax. Then, when the alarm goes off get up immediately, stretch a bit, etc.

Do this a couple of times (3, 5, 10 ;) and your brain will get used to the idea of getting up when the alarm goes off. Works like a charm for me (I tend to fall into the snooze-habit too)

This is not my idea, BTW, I got it from Steve Pavlina ([http://www.stevepavlina.com/blog/2006/04/how-to-get-up- right...](http://www.stevepavlina.com/blog/2006/04/how-to-get-up-right-away- when-your-alarm-goes-off/)) but I thought I'd summarize the long article for you ;)

</comment></comment></comment></comment></comment></comment><comment><USER16> carl sagan's "dragon's of eden" also touches upon these themes, and is very cool (imho ofcourse).

</comment><comment><USER17> People are very good at fooling themselves. However, there are certain traditions which contain knowledge of how to do better, and how to think more rationally. People utilizing this knowledge have made considerable progress. The best example is the scientific tradition. When you want to understand a top-quality scientist, acting as a professional, the first thing you need to understand is the scientific tradition, and you don't need to worry so much about common irrationalities.

We are not doomed to always be irrational. We can create knowledge and, with effort, remove errors from it. Then, when we have supporting knowledge, we can act reasonably rationally.

<comment><AUTHOR> Very common misconception - science as a process is rational, but scientists are people, and they fall for all the same traps.

There are plenty important scientific discoveries accepted only after the generation change. Bayesian statistics is one example of such process happening right now. Instead of being accepted or rejected based on the merits, the process of acceptance is being dragged along with all sorts of totally human irrationalities.

<comment><USER17> You seem to be referring to Kuhn's theory of Scientific Revolutions, which is false, as explained in _The Fabric of Reality_ chapter 13.

BTW Bayesian statistics as a replacement for science is not being accepted because it's no good. It's no good because it does not deal in _explanations_.

<comment><AUTHOR> Some very good arguments of Science vs. Bayes: <http://www.overcomingbias.com/2008/05/science-or-baye.html>

And explanations that people care about are just that what the link is all about - rationalization. Or in other words just because there is no good "explanation" for QM doesn't mean it shouldn't be accepted.

<comment><USER17> I have already seen that. It has the error I mentioned.

As for raw QM, it corresponds to reality, but people are right to also want to know what it means. And we do know. MWI is a good explanation of QM. There's no need to be an instrumentalist, and being one is not a way of overcoming bias. Explanations of what bias is, and how to overcome it, are one of our major tools against it. (See, again, _The Fabric of Reality_ on MWI (chapter 2), instrumentalism (chapter 1), and about explanations in chapters 1,3,4,7 and mixed in throughout.)

The book QED by Feynman also contains very good explanations about QM, but without mention of MWI, so you can see that even with no particular interpretation of QM there is a lot of scope for explanation.

<comment><AUTHOR> All the explanations you are talking about are very nice, and give you a lot of warm comfort, but they all are just rationalizations. There's not much you can predict about the rest of the world using them.

The cold rationality lies in the math you have to study for 2-3 years to learn how to add up these little amplitude arrows. Using that you can actually model and make predictions.

Another great example is Maxwell, he got all the rationalizations "wrong" but the math survived and is called after him.

<comment><USER17> You are presenting an explanation of why I should discount explanations in general. Isn't that a contradiction?

<comment><AUTHOR> Exactly, I'm being irrational here too - I'm addressing your irrational self that would listen to the arguments of a stranger for no good reason :)

Here's the kind of arguments I would find rational - [http://www.amazon.com/Probability-Causality- AI/lm/R2GX832Q1M...](http://www.amazon.com/Probability-Causality- AI/lm/R2GX832Q1M6CHV/ref=cm_lm_byauthor_full)

<comment><USER17> Since you believe you are irrational and make decisions based on bias, and Bayesian anti-science positions forgive you for this, whereas I do not (for example, science says the source of an idea is irrelevant, so you are wrong to be concerned with whether the source is a stranger), might it be that you only believe these anti-science ideas because of bias? They offer you comfort, and you revealed earlier that you do think about ideas in terms of which are more comfortable.</comment></comment></comment></comment></comment></comment></comment></comment></comment>


Google can divide by zero - <AUTHOR> http://www.google.com/search?q=tan+(pi%2F2)

<comment><USER2> Google is correctly computing tan(round_double(Pi/2)) -- it evaluates each subexpression as a double-precision floating-point value.</comment>


MIT creates hydrophobic material  - <AUTHOR> http://www.extremetech.com/extreme/138315-mit-creates-hydrophobic-material-that-could-revolutionize-fossil-and-nuclear-power-plants <comment><USER2> Why is this amazing advance neither voted nor read? It's a 10,000 X improvement!! This can completely change the economic equation for desalination plants, improve efficiency in so many other areas....</comment>


Chrome Users Coming from IE - <AUTHOR> http://www.inquisitr.com/3031/chrome-internet-explorer/ <comment><USER2> Chrome likely is pulling others from IE because it can often be installed with non-admin privileges.</comment>


Apache Spark Machine Learning with Large Data - <AUTHOR> http://www.kdnuggets.com/2015/11/petrov-apache-spark-machine-learning-large-data.html <comment><USER2> Original: [http://fullstackml.com/2015/10/29/beginners-guide-apache- spa...](http://fullstackml.com/2015/10/29/beginners-guide-apache-spark- machine-learning-scenario-with-a-large-input-dataset/)</comment>


SpaceX's Starlink Constellation construction begins - <AUTHOR> https://www.universetoday.com/141980/spacexs-starlink-constellation-construction-begins-2200-satellites-will-go-up-over-the-next-5-years/ <comment><USER2> >> Starlink is also going to be seeing competition in the coming years thanks to companies like OneWeb and Telesat, which plans to create smaller constellations that will offer service by 2021. Tech giants like Amazon and Samsung have also announced plans to deploy their own constellations, which would consist of 3,236 to 4600 broadband satellites, respectively.

SpaceX has a huge advantage in launch costs here. Mass produced satellites will be lower cost per unit than most others, and launching on used rockets will give them the cheapest deployment costs ever. And they are the only company that can reuse rockets today. I don't see the competitors really having a chance.

<comment><USER3> Anyone can buy a launch on a SpaceX rocket.

<comment><USER4> At the same cost SpaceX pays for a launch? That seems improbable to me.

<comment><USER5> depends what you mean. If you think of it as a "replacement" of another launch they could have sold, then yes, it's the same cost. Lost profit opportunity is lost profit is a cost.

But if it means they can increase the # of rockets they build, they might pick up some efficiency gains on the back stretch. I'm pretty sure they're already struggling to keep up with demand, tho.

<comment><USER6> SpaceX keeps rockets other customers "paid" for after they've landed (the customer pays for the flight, not the rocket). They've amassed a fleet they never had to pay a dime to construct.

I believe they have eight block 5 Falcon 9s that landed successfully. More if you count previous generations, but those likely won't be reused.

<comment><USER7> Does the price of a launch completely cover the cost of construction (excluding R&D)?

<comment><USER8> It does, for the competition, and there is no reason for SpaceX to go much lower as long as they don't build excessive overcapacity that needs to be filled.

</comment></comment></comment></comment></comment></comment></comment><comment><USER9> The true power of such systems is that they might eventually help overthrow hegemony of the BigTelco, who have been in bed with governments for as long as they have been in existence.

I'm excited to see what this would mean not just for the internet but mobile communication systems that are so much dependant on a few vendors and MNOs that have time and again proven to breach on privacy repeatedly [0][1]. For instance, there's no viable open source baseband alternative for 4G+ mobile devices [2][3][4][5], and acquiring frequency and setting up base stations is mired neck deep in regulations and patents [6], so there is not much room for a startup to disrupt the incumbent.

Given the advent of eSIMs and increase in embedded SecureElements [7] in smartphones, the traditional way of going mobile might soon be gone for good. I, for one, can't wait.

\---

[0] [https://news.ycombinator.com/item?id=17081684](https://news.ycombinator.com/item?id=17081684)

[1] [https://news.ycombinator.com/item?id=6722292](https://news.ycombinator.com/item?id=6722292)

[2] [https://github.com/srsLTE/srsLTE](https://github.com/srsLTE/srsLTE)

[3] [https://telecominfraproject.com](https://telecominfraproject.com)

[4] [https://www.opennetworking.org](https://www.opennetworking.org)

[5] [https://osmocom.org](https://osmocom.org)

[6] [https://news.ycombinator.com/item?id=11931072](https://news.ycombinator.com/item?id=11931072)

[7] [https://www.nfcworld.com/2018/08/07/357810/android-9-nfc- sec...](https://www.nfcworld.com/2018/08/07/357810/android-9-nfc-secure- element-tee-biometric-security)

<comment><USER10> I don't see why SpaceX will be any better than traditional telcos

<comment><USER11> They probably better than most telcos in suburban and outermost regions.

<comment><USER12> Oddly, thanks to fixed point wireless broadband, outlying areas often have more competition than urban areas (at least in the US)

</comment></comment></comment></comment><comment><USER13> I really recommend watching this simulation of how the Starlink Constellation would massively cut global internet latency: [https://www.youtube.com/watch?v=AdKNCBrkZQ4](https://www.youtube.com/watch?v=AdKNCBrkZQ4)

</comment><comment><USER14> Does anyone work on building satellites like the ones mentioned here? what is a normal day in the life at a job like that? Are you pulling 40+ hrs/week ?

</comment><comment><USER15> At some point SpaceX is going to start flying the Superheavy, which will be able to carry hundreds of satellites at once, and cost less per launch than Falcon 9 because the second stage will be reusable. That will give it a huge cost advantage.

<comment><USER16> Doesn't distribution in space become an issue if you release several hundred satellites from the same rocket and need to get them into position without any collision risk?

<comment><USER17> SpaceX has released dozens from a single launcher. They have get released in a staggered fashion and use onboard thrusters to modify their orbits a bit after release.

</comment></comment></comment><comment><USER18> Semi-Joke: Will/Could they fund this with a high frequency trading strategy?

<comment><USER8> If they do actually beat microwave towers, HFTs will be their first and most enthusiastic customers. SpaceX would not even need any specific strategy for the money to come from HFT. For biggest revenues, add steeply tiered pricing for the best latency, maybe even a bidding process.

If they tried to keep those gains in-house and did their own HFT I would not be surprised if exchanges then found ways to define rules that weaken HFT as a whole. Just a gut feeling that you need to be part of the culture surrounding the exchanges to be in that game and keep winning.

<comment><USER16> You don't even need to beat microwave. NYC-Tokyo or London-Tokyo don't have microwave links (and won't have anytime soon) so using it for these very long distances could be worth it.

</comment></comment></comment><comment><USER19> I wonder how this will affect Iridium in the long term. They target applications that provide critical services with low bandwidth requirements, and a need for small lightweight antennas with low power use.

Starlink's design doesn't fit those requirements for now. But I'm not sure whether Starlink will stay out of that market if they will be continuously upgrading their swarm.

On the other hand, it would be strange if SpaceX destroyed Iridium's business model after launching their latest generation satellites for them...

<comment><USER20> I could see a market where you put up a Starlink base station, which communicates to regular phones via LTE or WiFi. That could cover the use case of many Iridium deployments, where you are always within range of a camp or vehicle.

</comment></comment><comment><USER21> Couple questions (curious if anyone knows...)

>> ... averaging 44 satellites per launch.

How big are these things and how many can _actually_ be put up in a single launch?

>> However, SpaceX intends to use this to their advantage by gradually replacing inactive satellites ...

What happens to inactive satellites? Do they de-orbit themselves in safe locations? Or just stay as space junk?

<comment><USER17> They'll be in low orbit, so they deorbit on their own in months/years due to atmospheric drag. The ISS requires regular boosting for this reason.

44 in one launch is very doable. They've done 64 in a launch before: [https://www.google.com/amp/s/phys.org/news/2018-12-spacex- sa...](https://www.google.com/amp/s/phys.org/news/2018-12-spacex- satellites.amp)

<comment><USER21> >> carrying 15 micro-satellites and 49 CubeSats

IANASJ (I am not a space junkie) but this makes those ones sound unusually tiny and brings me back to the first question - are the Starlink birds similarly sized?

<comment><USER22> Most people on r/spacex are guesstimating that each falcon 9 will launch 25 satellites. 44 has been discounted because many think the falcon 9s fairing will be volume limited when launching that many satellites.

That being said, no official number has been given out by spacex so this is all guesswork and this article did not cite a source for the "44 satellites per launch".

</comment></comment></comment></comment><comment><USER23> Off topic, but can anyone comment on their experience renting a portable internet satellite receiver or provide a recommendation. Thanks.

<comment><USER24> Depending on where you are going you options are probably Iridium Certus, BGAN, or Thuraya.

I believe groundcontrol.com sells or rents all three.

</comment></comment><comment><USER25> I wonder how many subscribers at what price this project requires to be successful/sustainable.

<comment><USER26> Depends on a bunch of variables of course but ballpark a few million monthly users would probably be good enough.

The falcon heavy launches are going to be ballpark somewhere around 90 million. So excluding the satellite construction that's what it costs to launch around 70-100 satellites. They need at least about 30-35 launches. So ballpark that means a it is going to take probably 3-4 billion. Of course that is excluding the production cost for the satellites and other infrastructure. Lets call it 10 billion altogether, give or take a few billion.

Not a crazy amount to spend on infrastructure in the telco world. German operators paid tens of billions just for spectrum licenses. Considering you'd be able to compete world wide with this, 10 billion is a bargain.

It's still a lot of money of course but with a few million customers paying in the order of 10-40$ per month it would earn it self back quite rapidly. Even at the low end of that price range. Arguably they could charge more.

<comment><USER27> We also need to factor in the cost of replacing all the satellites every 5 years or so, as they only last this long in the super low orbit that they will be in. So it's ~10 billion every 5 years, not just once up front.

So 10.000.000.000 / 5 / 12 = 166.666.666 bucks per month

Say an average subscriber pays 20 bucks.

166.669.666 / 20 = 8.333.333

You'd need about eight million subscribers paying an average of 20 bucks a month to keep the business sustainable.

<comment><USER20> Compared to the $200 Comcast bill I would be more than willing to pay $50 a month for this, plus another $100 for video content. The big question I have is how many subscribers can they support per square mile in higher population density areas?

</comment></comment></comment></comment><comment><USER28> SpaceX, OneWeb, Amazon. I hope this will not turn to be a space debris disaster.

<comment><USER29> No, it won't. These satellites are placed close to earth, so they will deorbit after some time. An orbit this close to earth is not sustainable, you need fuel to keep the orbit going. Once the fuel runs out, or the satellite malfunctions, it will fall back into the earth's atmosphere and burn.

It's also in the article:

> Second, there's the matter of attrition, as satellites will begin to deorbit > after a few years and SpaceX will need to replace them regularly in order to > maintain its constellation.

<comment><USER30> SpaceX is going to be putting thousands of satellites in the ~750mi orbital range, which takes centuries to decay.

So long as they are closely tracked I don't think this is an issue, but these things are not meant to decay on short lifespans.

</comment></comment></comment><comment><USER31> Am I silly to worry about the amount of space junk all these companies are gonna contribute?

</comment><comment><USER32> I don't believe the required billions of financing for this project has been obtained yet.

I am skeptical of the utility, since most humans live in dense cities, where it is both cheaper and faster to run fiber (even to 5G towers) than it is for millions of people to choke on a handful of satellites. This offering is only compelling for regions that have no people and no infrastructure (and therefore no money). All signs point to another Teledesic or Iridium.

<comment><USER33> You may be underestimating the resentment with current duopoly operators in the US. I live in a dense city and I would switch in a heartbeat even if Starlink didn't offer better/faster/cheaper service. Just being on par would be enough.

<comment><USER34> That's a very niche view. Almost nobody will switch isps because of a duopoly if everything is currently fine on price and performance.

<comment><USER35> But everything is _not_ currently fine on price or performance. Most places don't even really have a duopoly. It's a single cable TV/internet operator and a single DSL operator, the DSL is way slower than the cable and both are overpriced. If you add SpaceX service to the mix I think you'll quickly see major price drops and equipment upgrades from most major terrestrial ISPs.

<comment><USER36> See: Google Fiber. When they started rolling it out, ISPs were folding themselves backwards trying to convince people not to switch.

Anecdotal, but I remember someone on Reddit from Kansas City mentioning that Time Warner had offered them something silly like 100M/10M down/up for _more_ money than the incoming Google Fiber was going to be (for 1Gbps synchronous).

I have no idea what the situation is like now, but I'd imagine it's gotten better. They aren't going to sit around wasting money when infinitely better tech is knocking on their front door.</comment></comment></comment></comment></comment>


Ask HN: How to improve and measure verbal communication skills? - <AUTHOR> In 2018, I'm attempting to improve my verbal communication skills.
I seem to lack the ability to clearly and consistently articulate my thoughts.
I work with a medium sized development team (~100 ppl), and although I'm an decent developer, I sometimes struggle to verbalize my ideas clearly.
I'd like to improve this skill, and somehow measure it throughout the year; right now I'm shooting blind. Any ideas on optimizing this skill? <comment><USER2> Read books and actively read them by making sure you understand what you've read and be aware of the author's sentence and paragraph structure. Copy(write) what you read by putting it in your own words. Do it over and over again and eventually, you'll improve your verbal skills. It's a slow process but that's what it takes.

Taking classes is not enough. It comes down to practice, practice and practice.

Also, keep a diary, it forces you to summarise your thoughts.

<comment><AUTHOR> Interesting, I like this idea, I will try this. Thanks.

</comment></comment><comment><USER3> It is more comfortable to talk with people side by side than face to face. I have had lots of good conversations with people while carpooling or walking somewhere together.

My oldest son has output difficulties. Walking together while he does most of the talking has helped him enormously.

Most of the time, I enjoy listening to my son. If you can similarly find someone in your life who enjoys listening to you and doesn't mind acting as a sounding board, just having the time to practice can really help you hone this skill.

</comment><comment><USER4> Join a community or corporate Toastmasters. The combination of prepared speech making, impromptu speaking challenges offered in every meeting called "Table Topics", and leadership skills development will be a cheap and efficient way for you to experiment and grow skills quickly. Also a safe place to stumble, fall, pick yourself back up and succeed with no career risks.

<comment><AUTHOR> Thanks. This is great advice. I was part of a Toastmasters and the "Table Topics" were really challenging for me, but are exactly what I need to work on.

</comment></comment><comment><USER5> That's a great question. From my experience one way of getting better is go to workshops. During training you get knowledge and also feedback, often you work in groups and people are more open to giving honest feedback than in real situations.

</comment><comment><USER6> Yes. I've been trying to improve this area for a while as well. Here's some things I've come up with. I'd really like to hear about other people's exercises / practices, etc. if they have any. Its hard to measure improvement though in a non-subjective way. So anyway here's what I've come up with up to now.

1\. Grab a random topic, record yourself explaining it. Listen back to the recording. Try to notice anything that you don't like, for me this is awkward pauses, saying some words repeatedly such as "right" or "uhm" and in general not having a fluid and coherent flow of thoughts and phrasing.

2\. Take a particular situational goal: i.e. convincing someone to do something, making a joke, acting out a scene in a film. Record yourself acting out the situation. Listen back and see if you were able to convince yourself, or you laughed at the joke or you could hear the emotion from the film scene. For me the craziest of these is telling a joke. Its amazing how much difference super slight pauses or minute changes in intonation can make. It can completely make or break a joke.

3\. Teach classes or do presentations at meetups / group events. If you can record yourself and listen back to it afterwards. See if you can keep your own interest. Try to fix things you find annoying with yourself.

4\. Find other people you find really impressive. For English, I think Ben Shapiro is one of the clearest, fast pace speakers on the planet. I also like the precision with which Sam Harris speaks, so I listen to these two a good bit and try to take the best from their speaking styles and incorporate it. The key is to actively listen to what they're saying and how they are saying it, trying to figure out the techniques.

In terms of measurement, be sure to save your recordings. Then you can listen to yourself at the end of every quarter or half-year and see if you can notice improvements. Also actually measure how many times you've put yourself in situations such as giving presentations, speeches, etc. That's another way to at least quantify your experience and whether or not you are giving yourself a chance to improve.

<comment><AUTHOR> These are really good ideas, I'll give some of them a shot.

I routinely listen to Sam Harris, his explanations are amazingly clear and concise. It's quite impressive.</comment></comment>


Speculative buffer overflows: attacks and defenses. (Spectre BCBS) [pdf] - <AUTHOR> https://people.csail.mit.edu/vlk/spectre11.pdf <comment><USER2> Isn't it funny how the researchers directly address Intel for HW mitigation,

> We also believe Spectre1.1 speculative buffer overflows are completely > addressable by hardware

but Intel passes the ball over directly to OS vendors:

>Intel recommends checking with your Operating System Vendor(s) for updates or patches.

Intel HW proposals so far (CAT) do not help at all with Spectre 1.1, the here proposed SLoth and DAWG does help with Spectre 1.1 but not with Spectre 1.0. Looks like HW vendors really need to offer more HW state for all speculative branches, caches, address translations.

> All footprint attacks can be prevented by carefully partitioning > microarchitectural state. For example, DAWG proposes hardware mitigations > that securely partition all microarchitectural memory structures (set- > associative caches, TLBs, PTE caches, etc.) to protect against both non- > speculative and speculative footprint attacks. > [https://eprint.iacr.org/2018/418](https://eprint.iacr.org/2018/418)

<comment><USER3> Assuming the problem can be mitigated in software[0], it is far more realistic to expect OS vendors to supply updates and people to install those updates than it is to expect Intel to fix their CPUs and people to replace their CPUs.

Conveniently, a software-fix is also much, much cheaper for Intel, but it is also much, much more convenient for me to install an OS update than it is to replace CPUs in servers and desktop machines; in laptops/tablets, that might not even be possible without sending the devices to the manufacturers, which equals massive downtime.

Of course, if Intel were to release their next generation of CPUs without fixing those problems, that would make a lot of people really angry. Some interesting litigation might ensue.

<comment><USER2> SW patches for HW design errors are only tampering over the problem. And definitely slower.

<comment><USER3> Oh, I agree that Intel has to fix their hardware. But I do not think that it would be realistic to expect them to replace everyone's CPUs.

I mean, morally speaking, that is exactly what they should do! But think of the pure logistics nightmare that would cause, not just to Intel themselves, but also to PC / laptop / server vendors. And last but not least, I would much rather roll out an OS update to our clients than walk around the entire company and replace CPUs.

</comment></comment></comment></comment><comment><USER4> Does anyone know if a CVE number has been issued for these?

<comment><USER5> [https://01.org/security/advisories/intel- oss-10002](https://01.org/security/advisories/intel-oss-10002) (CVE-2018-3693).</comment></comment>


Cute riddle: Four kids holding one toy balloon - cool-RR http://blog.ram.rachum.com/post/34561608024/cute-riddle-four-kids-holding-one-toy-balloon

<comment><AUTHOR> I used to find these questions amusing and even stimulating but after a decade of getting refused jobs because I couldn't answer questions such as this or some question about pirates to the satisfaction of an interviewer has made me slightly embittered.

And remember, no matter what, there's only one correct answer: _the one the interviewer wants to hear_. Very rarely do I see a new and correct answer to these puzzle questions provoke a positive response.

I hit the back button and moved on with my life.

</comment><comment><USER2> Problem with puzzles like this - if you see the answer quickly, what do you do? Any conversation fills up with uninformed, idle speculation, then someone kills it with the answer, then it's kind of all over.

What would be interesting would be to have a site that solved the problem of puzzle sharing and cooperation. Has anyone done that?

<comment><USER3> You know, that would make an awesome riddle... How do you pose a riddle and only accept answers that won't stop the discussion about the riddle...

<comment><USER4> It's called "NoScript". I have yet to see the solution on the site :D

</comment></comment></comment><comment><USER5> [SPOILER] If you're a visual person, the solution is expertly drawn out here: <http://i.imgur.com/Jpn1k.png>

<comment><USER6> Of course, this assumes there is no friction or that friction is negligible compared to the upward pull of the balloon...

</comment></comment><comment><USER7> Spoiler.

Apply this recursively: <https://dl.dropbox.com/u/388822/balloon.png>

Works for any number of children.

<comment><USER8> Does this work for odd number of children?

<comment><USER7> Sure: <https://dl.dropbox.com/u/388822/oddballoon.png>

</comment></comment></comment><comment><USER9> Assumptions:

\- we have balloons with no rings (just a knot ;-))

\- we can't add any rings (cheating!)

\- we can make rings out of strings

\</comment><comment></comment><comment></comment><comment></comment><comment></comment><comment></comment><comment></comment><comment></comment><comment>--

Solution: 1 string that makes a ring under the balloon, 1 that goes through that ring and has two rings at each end. 1 string through 1 ring for kid #1 and #2, 1 string through the other ring for kid #3 and #4. 4 strings in total ( general function f(N,M) => f(4,1) = 4 )

For 1 balloon an three kids you need 3 strings (1 as a ring under the balloon, 1 string through the ring. One end is held by kid #1, other end is a ring. 1 string through that ring and the ends are hold by kid #2 and #3) f(3,1) = 3. Likewise: f(2,1) = 2 f(1,1) = 1 <= trivial

Now for M balloons with M > 0\. For 1 balloon you can have 1 string that makes a ring, for 2 balloons 1 string as well (interconnected). For 3 balloons you need 2 strings from 1 to 2 and from 2 to 3. Ergo: for M balloons you need M-1 strings.

Consider the fact that having 2 balloons or 100 balloons, you only need to attach a string to one of these interconnecting strings to float all the balloons if you release this string.

Hence: M balloons and 2 kids needs the same amount of strings for for example 1 balloon and 2 kids plus the interconnecting strings.

From here it follows that for M > 1 (and N>0) the general function is: f(N,M) = (N-1) + (M-1) (in words: you need M-1 interconnecting strings and one string less than the number of kids)

3D plot: [http://www.wolframalpha.com/share/clip?f=d41d8cd98f00b204e98...](http://www.wolframalpha.com/share/clip?f=d41d8cd98f00b204e9800998ecf8427ecs5d2lubni)

</comment><comment><USER10> One of the possible ways is like <http://erikdemaine.org/papers/PictureHanging_FUN2012/>

"We show how to hang a picture by wrapping rope around n nails, making a polynomial number of twists, such that the picture falls whenever any k out of the n nails get removed, and the picture remains hanging when fewer than k nails get removed"

<comment><USER11> The two-nails problem is my favourite nerd-snipe. It can be explained to anyone without a math background, it can be solved on paper, it isn't a "trick" problem, and it isn't immediately easy.

The problem: hang a painting with one unbroken piece of rope going from one corner of the painting to another around two nails such that if either nail is removed the painting will fall.

</comment></comment><comment><USER12> The balloon has a loop underneath, you then let 2 kids (A and B), hold a thread between them, take a second thread, feed it through the loop, once around the thread between A and B, back through the loop and hands the ends to kid C and D. If any of the kids let go, the thread will unwind and the balloon is free.

<comment><USER13> I don't really get it. Why would the AB thread go off if any one of the CD let go?

<comment><USER14> Because the CD thread is the only thing stopping the AB thread from pulling back through the loop.

</comment></comment></comment><comment><USER15> 1: holded

0: not holded

binary AND: ==O--

binary OR: ==>\--

So the generalized riddle for any monotone boolean function can be easily solved because all boolean monotone functions can be built up of binary ORs and ANDs.

(Edit: accidentally mixed up OR and AND, fixed now.)

</comment><comment><USER16> Possible solution (I can't see the comments in the original post; are those facebook comments?). The balloon is attached to a ring, and a thread (A) passes through that ring. This thread has a ring at each end, and these rings are smaller than the ring attached to the balloon.

Finally, a thread passes through each ring of thread A; let's call them threads B1 and B2. Each kid holds one end of threads B1 and B2.

If for example one of the ends of thread B1 is lost by its kid, B1 will slip out of the ring on thread A, and thread A will subsequently slip out of the ring on the balloon. The ballon flies away :)

</comment><comment><USER17> This looks similar to the picture-hanging puzzle, where a picture is hung around a number of nails, and the removal of any one of them will cause the picture to fall.

<comment><USER18> I believe it is exactly the picture-hanging puzzle, upside-down.

</comment></comment><comment><USER19> Tie a knot in the thread to the balloon, then trap this knot in the middle of a gap between two twisted threads, the ends of these held by the children.

</comment><comment><USER20> I think this is related to Borromean ring system - three inseparable rings, yet no two are directly linked to each other. Cut any one ring, and the other two fall apart.

<http://en.wikipedia.org/wiki/Borromean_rings>

</comment><comment><USER21> A small, square cloth or net covers the balloon. Each kid holds a string attached to a corner of the net. If just one kid lets go of a corner, the balloon rolls out of the net and into the sky.

<comment><USER22> The balloon will go in unstable equillibrium in this case.

</comment></comment><comment><USER23> Chain link system.

Each string acts as one chain link. Kid technically could hold both ends of their string, but you could tie it if kid holding one string was an absolute condition.

</comment><comment><USER24> Feel free to remove/censor/hide my posted solution if you want to keep it going for a while longer. Mind you, there are almost certainly other solutions to this puzzle.

</comment><comment><USER8> I find the riddle and the answers amazing! But the answers I saw were only for even number of children. Is there a good solution for odd numbers?

</comment><comment><USER25> Who says it's the way the thread is arranged? Maybe the helium would lift the other kids up if one decides to let go.

<comment><USER13> The question did ask how the thread is arranged..

<comment><USER26> Well, he did write "threads"

> "How are the threads arranged?"

So the whole 4 separate threads idea still holds if we assume the balloon will lift the kids off the ground. That was a bit of a huge hole in the riddle. It should have been noted that the children were immovable anchors. Feynman would have had a field day with this.

</comment></comment></comment><comment><USER27> Easy! Make the balloon large enough to lift N - 1 kids!</comment>


Ultra-Geek Linux Workstation Guide - <AUTHOR> https://begriffs.com/posts/2017-05-17-linux-workstation-guide.html?hn=1 <comment><USER2> I love that you are really serious about security ! Personally, I simply use Yubikey with its PIV capacity, but this article gave me nice ideas =)

</comment><comment><USER3> This is awesome!</comment>