skysight-inc/HackerNews huggingface dataset:
It's not always the most efficient for every car, but there are lots of charts showing this tradeoff. Some cars are more efficient at 65 or 70 than 55 (97 Celica), but in modern gas cars, 40-50mph is where you hit a peak, and you start getting worse from there. 40mph on the highway is painfully slow though, so people generally pick an optimal point higher than that.

(One inconsistency I've found is how the Motor Trend test below sees a very high peak at about 40MPH and a decline after, while other sources show a flatter peak). And 55MPH seems more like a magic number the author picked, but not a bad one if we don't know the model.

Generally cars are geared so the engine begins entering its optimal / most efficient RPM range where it can produce more torque in top gear around 40-50mph, and rolling resistance and wind drag (which is a cube function of speed) contribute to make mileage worse after that. Usually the speed at which you first shift into top gear and cruise comfortably is close to optimal. Efficiency doesn't start dropping for a while because of the cubic nature of drag, and the engine sometimes is more efficient at higher RPMs for a bit (see nols' post on manufacturer optimization).

Fun fact: At top speed (254mph), a Bugatti Veyron will use its 26 gallon tank in 12 minutes.

An older chart:

http://upload.wikimedia.org/wikipedia/commons/a/a9/Fuel_econ...

A newer chart:
http://blog.automatic.com/wp-content/uploads/2013/12/mpg-vs-...

Motor Trend chart:
http://image.motortrend.com/f/roadtests/sedans/1208_40_mpg_c...

http://www.motortrend.com/roadtests/sedans/1208_40_mpg_compa...

(One thing that bothered me is how the Civics in the last two charts were so different)
Generally the most efficient is highest gear-lowest RPM, and with car makers that's usually around 55-60. You could change the fuel efficiency to different speeds(I'm sure they're adapted to local markets with metric vs Imperial), but it would be worse off for most people to do that. It's not simply a gearing issue to change fuel efficiency, it's also the ECU controlling the fuel/air going into the engine. They aim for optimal fuel efficiency for normal driving, and that seems to be the sweet spot.

Contrary to what I've heard before, changing fuel efficiency to higher speeds wouldn't make things better. It's also not that simple because drag increases exponentially with speed.
"And because of the huge inertia in political discourse, the gap will have to reach something like 50% vs 20% before it even becomes acceptable to raise this as an issue."

The gap in achievement at later levels of schooling on an aggregate basis has been an active discussion for years already - we don't yet understand why, but it's an active area of interest, discussion and research.

As has the fact that the recession hitting those with lower levels of education harder are hitting men disproportionately.

Because you haven't heard about it doesn't mean it doesn't exist.
I've seen MikroTik router mentioned on HN quite few times, and have been wondering how is it better compared to say, Broadcom-based routers running OpenWRT/Tomato/DD-WRT. Could you clarify why? (I've looked at RB750GL, which looks very interesting considering its price, but still don't know how would compared to my current ASUS RT-N16+Tomato setup.)
Hell is other people, after all.
Most opinion-pieces on current controversies—as opposed to actual news—don't count as on-topic for HN.
I came in wondering the same thing. Why is this newsworthy? Every one of the replies to your comment is either a joke or an obnoxious lecture about "why maths can just be for the sake of it [and might be useful later]" like you're some sort of recently-thawed caveman. People can't just say "no, no actual applications yet, it's just cool," or, "I don't know." Ugh. Whole thread made me cringe.
Actually, no: having been a student pilot at one time, I spent a lot of time reading about the many things that went wrong with airplanes.

That doesn't mean I still don't think this is a bad idea.
>there were and are very few researchers working with the opportunity mix necessary. They had five years of freedom from business concerns, tons of ambition, the right context, intelligence and inspiration.

A lot of Universities and research centers have the same. As most of them are, arguably, not a PARC may be these conditions aren't important? On the other side, we do have a lot of R&D coming out of Universities and research centers, so may be PARC isn't important?

i may sound like trolling, but i did listen live to Alan Kay once and honestly got more confused and got more questions as a result :)
The odds are probably not high, just high enough. It's more of a statistics game, and even with a relatively low rate of theft, occurrences will happen.

And when they do happen, they'll be very loud and publicized. That's probably what we see more often than first-person cases.
Exactly the kind of discernment we need.
Which is why I think the idea of change itself was an invention. Up until roughly that point in history people didn't apply themselves to change because they didn't even have the concept as it came to be understood.

Things progressed so glacially for so long simply because, from experience, nothing other than stasis could be imagined, not because we were any dumber. Change was the key innovation for change. Occasionally I wonder if it wasn't an inherently fatal discovery.

One wonders how many other such "basic" concepts there might be that remain hidden from view.
Also remember that the veil does not protect individuals from being found liable their own part in corporate actions. This is the basic promise of a limited partnership: I give you money to start your business. I am liable only to the point of my investment, but you are responsible for all of your decisions.

I think we should just treat corporate C-level officers as unlimited partners with regard to decisions made under their watch. That would mean effectively that business debts that the corporation could not pay would fall on the officers to guarantee, and that things like product liability would be treated a little differently.
Well yeah, but since it's likely everything experiences pain in some way (even plants), the "pain stimulus" model is flawed from the get-go. What people who use the model actually do is just set some threshold on their personal outrage or disgust scale and don't eat anything over that.

Or sometimes they just set the bar to where they think they're supposed to even if they don't necessarily even feel anything in particular about the issue. It's just more socially acceptable to eat carrots instead of house cats.
I use Dropbox to push data to my VPS.

BTW I edit code remotely using Vim + Netrw + SSH tunnel http://motyar.github.io/14/vim_fast_remote.html
I'm amazed that some people don't by default make a conscious choice of where to put archive extractions, Which would typically include deliberate creation of a new folder, named by them, in a suitable place in their archives.

The concept behind the term 'tarbomb', (I had to look it up) speaks most about user laziness and disorganization.
Why should a zip or tar archive contain anything other than the files it's advertised to contain? If they are nested in a folder, that just makes more work for me, since it's unlikely I'm going to be happy with the folder name as is, so have to rename it. Or more likely, move the files back up to the folder I extracted the whole thing into, then delete the now empty superfluous folder.
Why are Millennials investing so conservatively?
Either I did not understand the post or it is totally uncompelling. MPG makes much more sense to me. Gallons per 100 miles (or whatever) sounds very clumsy.
I highly doubt that a person stealing laptops from Starbucks is going to stab you.
Bitcoin believers: Why digital currency backers are keeping the faith
Not only Japan. Singapore and China are the same. When leaving in Singapore it took me a long time to trust it, but I never trusted leaving my laptop.

Sweden also used to be like that, but it's been changing over there.

Unfortunately most places are not like this. From developing countries (especially Brazil) to major touristy cities in Europe. :-/
55mph is a sweet spot where the engine is operating close to peak efficiency and air resistance hasn't yet exploded. There very much are cars that are most efficient at 65, but that is because they sacrifice efficiency elsewhere.

Peak efficiency is the intersection of many curves- gearing, rpm, aerodynamics, speed... Aerodynamics is possibly the biggest factor though, hence the common point of 55
Well... yea.. I suppose shit happens
A complication is when a car (or bus at bus stop, or whatever) is parked in the bike lane, or immediately on the curb lane, just before the right turn lane. In that case, it becomes a lot harder to get into the bike lane before making a right turn, and in SF, is a fairly common situation.

If you're just worried about cars, it's fairly safe to make the right turn lane from that non-rightmost lane, since the other car is blocking any other car from approaching there. However, bikes (and sometimes motorcyclists, but rarely are they that suicidal) are going to come up, so it's still prudent to both get into the far-right lane and check on the right. That's the most common "cars turning right from non-rightmost lane" situation I've seen, though.

My biggest question about California road rules: what kind of vehicle is a homeless guy with a shopping car full of cans/etc.? Is he a pedestrian (similar to a pedestrian pushing a stroller), or is he a vehicle like a bicycle? What if he's in a lane of traffic, going down the road at 1-2mph (which is reasonable, since he would take up the entire sidewalk otherwise).
Windows has GLSL as well.
the randomish automatically generated filename for fb photos is unique, and sometimes publicly accessible.
I was thinking of a technical definition of "entitlement" as a right granted by the government, not necessarily as a give-away to anybody.
I run a coupon related site that's targeted at a specific segment of the market. I was ranked at the top 1 or 2 sites for a few pretty popular keywords for a while, until the summer of last year when I changed the domain, and my rankings dropped off within about a month (despite setting up correct redirects, updating in Google Webmaster tools, etc. Believe me, I spent a LOT of time making sure I did it right).

I never could figure out why the search traffic dropped off. I didn't partake in any seo tactics (I honestly wouldn't have known how to), and my search traffic hasn't really recovered.

Interestingly, my traffic recovered based on direct and refferal traffic, so it wasn't as big of a problem as it could have been, but it does sadden me that I am missing out on a significant portion of the current market (to get new users), but I'm completely lost on why my ranking dropped.
Does somebody wanna give the layman's version of why I would use this?

I don't blame the site for this, given that it doesn't appear designed to be read by a layperson, but without some kind of I'm-Not-A-Crypto-Wizard translation it just reads like big-word-bingo to me.
> Citations, or you are just promoting your opinion.

This is an inherently flawed statement. If you follow the citations in a scientific paper at some point, the citations are going to end. A scientific article that consist only of citated information doesn't bring anything new to the table, it only summarises.
I agree with your general point. So maybe the following is the exception that proves the rule, but:

An acoustic piano has 88 keys, and classical or jazz piano music tends use many of them. Whereas a 60 key electronic keyboard is often subject to the Flock of Seagulls treatment, wherein one key at a time is held down. :) It's roughly like touch typing vs. hunt and peck.

But aside from that example, yes, I think you're onto something.
Yeah, Regexp::Assemble was what I had in mind. There's a few that try to generate a list of matching strings from the expression, but I've never been satisfied with their output. Either they're slow, or don't let you constrain the regex, and all of them don't generate comprehensive lists for some reason.
Thank you. And thank you also for saying so.
Citing the CAP theorem as a reason not to have a distributed system is like citing Arrow's Impossibility Theorem as a reason not to have a representative democracy. Proving the impossibility of a platonic ideal doesn't tell you anything about whether one imperfect system is superior to another in practice.

And you can't hand wave away the fact that the implications of the CAP theorem are minimal on a distributed system with a high level of interconnect redundancy. If you can ensure with high probability that there will not be a partition in the network then you don't need partition tolerance. If against all odds you have a partition anyway then you lose availability, but that isn't a characteristic unique to the CAP theorem or distributed systems -- any system will lose availability if enough redundant components fail simultaneously.
This is still not any more satisfying than "because this is the way they are built."

Also, I should say that I realize this is a side show. One that I think should get less attention. No matter how much more efficient you make a car, I doubt I would ever be able to do better than local transit. (I, of course, welcome evidence otherwise.)
University research is not free from business concerns either---the phrase "publish or perish" exists for a reason.
anyone else having issues with IP? Forget which thread it was, but someone stated that their IP showed up as X in once instance (What is MY Ip I believe) and Y in another.
But this offered nothing other than some slight preference with a compelling argument that the differences in spending are more obvious. Yet, even in stating this, the conceit is held that "higher mpg is always better."

So, my citations desire would best be settled by any sort of empirical study showing that they actually affected buyers in the desired way.
The recovery puzzle: New factory struggles to match jobs to job-seekers
Supposedly peak engine efficiency is at peak torque, but of course no car is designed to cruise at peak torque.
Weird but it just hit the top of hacker news today... someone else posted the link! Maybe it was my headline?
Since the title was false, I changed it to "Why UPS Trucks Rarely Turn Left".
Robot that Plays Threes
Yep. XSS on the other hand would be very hard to pull off with NoScript enabled.
As I stated in a sibling, this still boils down to "this is how current cars are built." I would imagine if you looked at the average vehicle built in, say, the 1940s, you would see a vastly different "optimal" number.

Which is all to say, do we expect this to stagnate forever at 55? Is this a hard physical limit? I understand drag gets higher there. Are there no tricks left to us?

And again, I fully concede that this is likely not the most pressing fact around. Just one I am curious on.
Could you resolve the issue by introducing an element of stochasticity into the distance players are displaced to avoid collisions?

That way, one player would move right (or left) more than the other player and the collision would still resolve itself.
Hah thats pretty cool. Felt like I was watching a real life super mario galaxy a little.
Spiped – symmetric, encrypted, authenticated pipes between sockets
This article is hilarious. It neglects to mention that computer science programs(engineering in general) is 90 percent guys.

Engineering is probably the hardest major from a math and hard work perspective.

Almost seems like women want a voice without having to do any of that pesky work.
What is the minimum commitment? Can I sign up for the $35/mo service to test drive and then cancel before the end of the first month.

A limited time trial configuration would be cool.
Being a man and an oculus tinkerer. How would I go about testing this?
Both men and women would benefit from learning more about nerd culture and women:

http://calculatedbravery.wordpress.com/2014/01/21/on-nerds/
A typical person drives a fixed number of miles per month, rather than using a fixed number of gallons of gas. So one advantage of "Gallons / 100 miles" is that it requires one fewer steps of arithmetic to figure out how much gas you need every month.
I Want – It is an app that allows users to earn Bitcoins helping others.
Even if I didn't knew from the beginning that someone will steal a laptop from the coffee shop, the moment I saw the MacBook left alone I probably was thinking "I hope you have it locked, or it will get stolen...someday".

OT:If you look in her wallet when she was paying, you can see that she's a little cash-strapped.
The situation you describe is indeed awful, if true. Yet I cannot see how it is related to the article posted. Unless I am mistaken, that was about different people doing other problematic things.
Perhaps we are supposed to view it as just tit-for-tat (no pun intended) in an ongoing battle of the sexes? If so, I really cannot agree with the context of your comment.
I hadn't played REDDER before. It's pretty fun. Reminds me of Metroid.
If you order the cheap stuff. PBR can go for as little as $4, or $3 in brooklyn
I remember running into a couple guys/geeks in the late 90s SV that had a variation on a fantasy involving them white knighting Chelsea into a torrid love affair. I think the mocking of her appearance earlier in the decade made her seem more attainable. Also, she was going to Stanford, so obviously she's into nerdy dudes.

I specifically recall overhearing a guy giving another advice about where she might likely appear on campus and at what time. One had a rather detailed plan for how he'd approach her. It was a weird time.
I understand the sentiment, but I think it's a mistake to think as Sony as one entity. I don't mean this is in the "there's scumbags and there's good people too" rosy way, Sony is really not one corporation but a constellation of indepedantly acting entities.

The Xbox business unit and the Windows unit are in the same organisation. Sony's playstation unit and movie business are not even the same company.
Correct me but, atm, it would be possible to use the keyword "let" to declare a local variable with a block scope if I remember well, isn't it?
Samsung researchers claim graphene breakthrough
"can compile into ... javascript"

I don't believe this is true, at least not easily.
Relatively short description of the design goal:

The goal of an encryption scheme is to provide confidentiality. It is important to know that most traditional encryption schemes, like block ciphers in CBC, CTR, OFB modes, do not provide any authenticity, i.e. while you cannot recover the plaintext from a ciphertext, you might be able to feed the decryption algorithm a ciphertext that you crafted, without the decryption algorithm having a means for detecting its lack of authenticity (e.g. flipping a bit in ciphertext generated with CTR mode will result in a flipped bit in decrypted plaintext), and in effect, making the system do things that an adversary wants it to do. In practice, this can often be more dangerous than loss of confidentiality.

In order to add authenticity to an encryption scheme, you would traditionally apply a separate message authentication algorithm to the ciphertext and the initialization vector to generate an authentication tag, which you can then use to verify if the ciphertext was tampered with.

There are many ways this combination can go wrong (and has gone) due to design and implementation mistakes, like sharing the key for the MAC and encryption algorithms, not authenticating the IV, not verifying the tag correctly and exposing yourself to timing attacks, applying the MAC to plaintext, as opposed to the ciphertext, etc.. For this reason, and performance implications, it is desirable to have encryption schemes that also somehow provide authenticity almost "for free", as a natural byproduct of the ciphertext generation. Encryption schemes that achieve that, like OCB, CCM, CWC, and GCM modes, are called Authenticated Encryption.

Most of the regular authenticated encryption schemes rely on passing a unique number when encrypting each message, called nonce or initialization vector. For instance, encrypting more than one message with AES in GCM mode with the same nonce will result in total loss of authenticity, among other things. Therefore, they are not very resistant to accidental misuse, and extreme care should be taken while using them.

AEZ, on the other hand, strives to be a more robust authenticated encryption scheme in the face of nonce reuse (misuse), that is, it will not face a catastrophic loss of security if a nonce is accidentally reused.
My cursory search suggests that it may be pretty secure: http://www.cvedetails.com/vulnerability-list/vendor_id-49/pr...

but I figured I should ask this guy, sounds like he knows what he's doing.
My understanding is that type providers define the types at compile time.
It's fine to make that assertion, but how do I know it's mathematically true, and what makes it true if so?
Small Business Lessons From "The Profit" TV Show
Would anyone give a more in-depth comment regarding why this didn't happen?
There's a common cliché, that C programs, as embodied in Unix, are probably the most widely used form of functional programming - or at least CSP. This example is idiomatic;

grep -c foo * | uniq | sort -rn

It's more than possible to structure C programs this way internally too, elegant even. Use forks and pipes if you want to keep it simple, build co-routines if you're up for it. It's probably the most practical and beneficial way you can re-apply the lessons of FP to C.

But the book doesn't mention either technique - just weird and ugly tricks to emulate tail-recursion, cons et al, probably the least effective parts of FP to try to use in C.
Please don't make aggressively sarcastic comments on Hacker News. It goes against our two most important values: signal/noise ratio and personal civility.
Haiku's Webpositive browser gains native HTML5 video/audio support
Well, I now notice Dryden was quoted in the article, though she does not seem to be involved in the events recounted in the story. So your comment is circumstantially related.
What I mean by (1) is that if you ask a mutual friend to display a picture I took in her gallery, I ask her politely to take it down, and she voluntarily complies with my request, the DMCA wasn't involved at all. This is how I understand the arrangement between YouTube and the 800lb copyright gorillas.
I'm confused by the title of this article. The copyright in the PDF is 1999, not 1997, and it says it's about imperative programming in C, not functional programming. It says it's for people who learned functional programming in SML, but now need or want to learn imperative programming.
To check the sha256 checksum on a system with openssl, in terminal find the download and do:

openssl dgst -sha256 spiped-1.3.1.tgz
In the comments section of the original article, the attacker (Phikshun) notes that he worked at the same company as his victim, so he was able to test the phish on himself to make sure it passed through that company's email security.
Everywhere? Try driving across Nevada or southern Utah.
Hello JIT World: The Joy of Simple JITs (2012)
So would having separate male and female versions of the Oculus be considered more sexist or less sexist? No snark intended.
Simone??
Never used GNU units, but Wolfram Alpha will also do this trivially [0].

[0] http://www.wolframalpha.com/input/?i=16+mpg+in+barrels%2Ffur...
Reading Hatching Twitter (http://www.amazon.com/Hatching-Twitter-Story-Friendship-Betr...) will give you a more historical and give a bit of context of how they evolved to where they are now.