Engineering Pornography (2002)
jwz.org
jwz.org
Like most failures, this is a systems failure. Someone engineered the hell out of that cable. But they neglected to realize that it would be drawn through a steel pipe.
"So, what went wrong? Varying load conditions in the three legs of the 3-phase circuit caused tremendously strong and dynamic magnetic field changes. The electromagnetic forces between the three conductors and the steel pipe (gack!) cause the conduit to wiggle around inside the pipe."
The other lesson is that you shouldn't hyper-optimize locally, and instead design for maintainability. I'm not sure what they were thinking when laying a cable that requires experts to be flown in from the east coast to repair. The simplest mechanisms are the ones that are the most easily repaired. The entire article goes on in great length about how awe-inspiring the engineering of this cable is, whereas I just see a bunch of complexity that probably didn't need to be there. The 118 layers of paper tape, and the oil pumps, and so forth. Surely there was a simpler solution. I'm sure after this failure and the ones on the east coast, they are not still laying cables like this.
Sometimes massive infrastructure requires massive repairs, but that doesn't automatically make it not cost-effective.
http://www.fujikura.com.sg/hv_xlpe.htm
At the the maximum voltage over XLPE was 110kV.
Sticking 2 of these cables side by side would have other interesting effects.
http://www.emfs.info/Sources+of+EMFs/Underground/multiple.ht...
It appears oil and paper systems are still used, but I don't think they use the high pressure oil system like the one in the paper.
http://www.hitachi-cable.com/about/publish/review/__icsFiles...
The issue is that this is 230 KV, vs. 230V.
A single excellent commercial electric wok is about 50-100A.
Each individual circuit is about 15-20A.
The really awesome thing now seems to be HVDC transmission -- eliminates capacitance problems and problems with multiple grids.
This. Imagine a global grid connecting alternative energy sources for each optimal locale: Geothermal in Iceland, Solar in North Africa, and of course Thorium in Norway.
Peter Thiel seems to think this scenario is improbable[1] but I don't think it takes into account ABB's recent breakthrough with HVDC switching[2].
[1] http://blakemasters.tumblr.com/post/23787022006/peter-thiels... [2] http://new.abb.com/about/hvdc-grid
Tell that to the Texas Department of Transportation, where any given highway project will typically run over time and budget.
As another commenter mentioned, the engineering involved in the story is likely not required very many places on earth. To be in a situation, developing a solution to a massive problem with little to no precedence is an exhilarating and terrifying position to be in. It may sound overly-engineered to you but, at the time, it may have been the most cost effective engineering solution to a problem rarely encountered.
The entire article goes on in great length about how awe-inspiring the
engineering of this cable is, whereas I just see a bunch of complexity that
probably didn't need to be there. The 118 layers of paper tape, and the oil
pumps, and so forth. Surely there was a simpler solution.
Take care that you don't come down with "Engineers' Disease", though - the
tendency for people with a high level of technical knowledge to decide that
their knowledge must be applicable to specialised fields that they don't
actually know a lot about.
Allow me to reverse your statement.
"I don't see why programming for multicore processors has to be so complex. Why not just run four copies of the program on all four cores?"
"I don't see why every web site makes you create a new account. Why not log into everything with my facebook account?"
"I don't see why the legal system has to be so complex. Why not just have the judge decide everything, and get rid of the lawyers?"
This is actually a good idea.
Message passing is more robust than the currently prevailing shared memory + thread spaghetti practice. Many/most problems being attacked with the latter approach can be reformulated to use message passing and looser coupling.
Actually for many web sites this is a pretty good idea too.
This is sort of like the electrical engineering equivalent of the Tacoma Narrows Bridge collapse:
https://en.wikipedia.org/wiki/Tacoma_Narrows_Bridge_(1940)#C...
In this case, the simplest mechanism would probably have been to build above-ground high tension power lines on massive steel towers. This is the most common mode of high voltage electrical transmission, and the cables are easy to access and repair. However, this cable was probably built when the area was already densely populated, and property owners would not have accepted having such an eyesore going through their back yards. So they had to bury it underground, which required heroic engineering to insure that it would only have to be maintained very rarely (designed for an MTBF of 60 years).
There are analogous problems in computer hardware. For example, if you want a computer to control a cardiac pacemaker, you can't just buy a generic server and throw a gigabyte-sized Linux distribution on it. It has to fit in a tiny space, run for years on a small battery and be 100% reliable. Very different from creating a web application, but the extra complexity and expense are necessary due to the problem that's being solved.
astonishing that they don't do this. Their first attempt failed; the second likely will also. And both at tremendous expense when a tried-and-true methodology exists.
This is about the most arrogant, ignorant thing I've read on HN. No. I promise you the electrical engineer who designed that feeder did not "neglect to realize" that a steel pipe is conductive and if the feeder came into contact with it, it would short. There were no doubt a number of considerations and trade-offs involved in the choice of material.
while this is a classic, my snark is thrashing against
its bonds. I could have sworn it said 'news' up there.
SENSATIONAL HEADLINE ALERT!!!
For reference, the headline I used was:
Engineering pornography - underground
power cables gone wrong
So on this submission, now even older, we have 16 comments (and counting) and 60 points (and counting). Has HN changed? I'm off to check some records ...
(pause)
A bit of hunting shows that this got at least one vote while still on the "newest" page, but it looks like it never hit the front page, which will part explain why it never got many comments or votes. Still, the tenor of the comments is interesting. I continue to learn.
So what are you saying?
So you are complaining that you didn't get the
karma 500 days ago that wallflower got?
Or are you just pondering the mysteries of stories
getting picked up?
I see it isn't the latter since in this comment
http://news.ycombinator.com/item?id=4097127
you indicate you've done research on that topic.
So what are you saying?
The dissonance between the comments there (even though downvoted) and the positive reaction here is also of interest. I thought I'd share that, hence my comment.
What I'm saying is that as soon as you find a fool proof way to submit something and have it show up on the front page, pg will 'fix' it so that you can't do that in the future just like linking the discussion in a blog post was 'fixed'.
I typically read the site from an RSS feed, which means I see everything that is submitted that makes it to the rss feed, regardless of whether it is on the 'new' page or has fallen off. I don't know what percentage of folks do that. There are also 'super powers' for some users but those are for the standard sorts of things (like make sure a YC company looking for people gets to the front page for a while).
Can you say more about what "improving the system" would entail?
My concern is that things that are clearly of interest (in the sense that they do eventually do get the upvotes in a subsequent submission) sometimes don't get noticed and don't get the upvotes they deserve (by some definition).
Or something.
> I typically read the site from an RSS feed, which means
> I see everything that is submitted that makes it to the
> rss feed, ...
> Can you say more about what "improving the system"
> would entail?
Aren't you assuming the value of an article is a constant? In practice, context changes and the value of an article goes up and down. Maybe today is a slow news day and 500 days ago was very busy. I wouldn't expect your average article about (say) Scala to do equally well on the day Facebook has its IPO and some day nothing interesting happened on. A controversial article about gun control is not going to be perceived as having the same value the day after a big massacre as leading up to an election or on a boring day in mid-January.
It's an interesting observation, though, that for some items the "value" changes over time. This particular item, I suspect, doesn't fall into that category. Context might be more important, but the analyses I do try to take that into account.
You're right that there isn't an objective standard for "value" (or at least, I don't know one, nor how to get one), but multivariate analysis can assign a number to an item which is broadly aligned with my intuition of the concept of "better". As a result, I'm trying to home in on finding items that my system predicts should be "of value" so I can read them, even if they don't make it to the front page.
Consider, I can train a Bayesian Filter with the page text of many submissions, and get that to predict what I'm likely to find "of value." But that means I don't see what the community might have found interesting but would be outside my core interests. These, too, are "of value" because they stretch me. I can't just train the filter with what makes the front page, because the evidence is that many things that "should" (by some definition) don't, and that would damage the training.
So it's complicated. I'm trying to find ways to improve the community and help me get more out of it (obviously) with less effort. I'm trying to help, but the hassle I get is just encouraging me not to make these observations out loud.
There was an interesting study from a few years ago that investigated what factors make a song a hit. They seeded various songs with various levels of initial popularity, and their general conclusion was that popularity begets popularity. Hence, initial conditions matter a lot, and they are largely random. (And if anyone can find that study, please let me know. I have tried multiple times to find it, but I can't.)
And the challenge in the analysis is to find the factors that affect it, and then add the randomness to get the right results. To find the underlying behavior, even when the data are affected by randomness. It is kinda what I do, and that's partly why I'm working on it. I'm learning things as I go, both about the techniques and methods, and about the HN "community".
Interesting study you mention - I've made a note both to look out for it, and to let you know if I find it.
Thanks.
This wiki article might be of interest too: http://en.wikipedia.org/wiki/Matthew_effect_(sociology)
I read about a similar experiment in the book "Automate This" by yc alum Christopher Steiner. They seeded a music website with unknown songs and it turned out that whatever was liked first benefited from the Matthew Effect. ie, people tend to like whatever is already labelled as "popular". Definitely an interesting study, but I fear we've gone far off topic.
The title can be read as "How to engineer pornography", at least that's how I read it at first. OP might want to edit it to remove any ambiguity.
I read an AMA on Reddit at one point from a guy who worked as a server engineer on some large porn website/network. The questions were mostly about engineering, but the answers were fascinating - when you think about it, porn networks have to face the same scaling issues as many startups, and they have some unique challenges (and also advantages) that other markets don't.
I was secretly hoping this post would be something along those lines. Interesting nevertheless, but not what I was expecting!
Hur hur hur.
Interesting.
It wasn't until I saw it on the EngineeringPorn subreddit that I realized what it really was and read it. Now I'm glad I did.
Something like "Engineering Porn: Fixing 230kV Underground Cables" would have done it.
Ouch. It must have been 'fun' finding that out. Another example of extreme water hammer: http://www.davros.org/misc/ambridge.html
Having played with some back in school, it's this gnarly paper that is super stiff, near invulnerable (to hand attempts at tearing and cutting), and really really good at giving paper cuts. It's also somewhat fire retardant, if I remember correctly.
So, it's not like the cable was wrapped in Christmas paper or something.
What exactly hurts your eyes? Are you fine with light gray on black? I can sort of understand disliking the amount of green, but if it's just because of the black background then you probably having lighting issues in your setup.
That sounds amazing and terrifying, sort of like the engineering equivalent of the old soviet dentists' belief that they have to poke cavities and judge their location and severity by how badly the patient reacts.
Wouldn't it be interesting to hear someone's lessons learned from using Lean Startup and A/B testing when entering the porn industry to discover best practices, instead of just using "Tried and True" methods?
Is porn an industry ripe for disruption?
I wonder if anyone has applied to YC with a pornography startup.
It's quite a classic solution for subway construction and restoration in the deep areas. In certain conditions, when tunnels get flooded with quicksand, liquid nitrogen can be used to isolate them.
I have to reset my difficulty meter for engineering problems now.