Announcing: Slashdot Deals - Explore geek apps, games, gadgets and more. (what is this?)

Thank you!

We are sorry to see you leave - Beta is different and we value the time you took to try it out. Before you decide to go, please take a look at some value-adds for Beta and learn more about it. Thank you for reading Slashdot, and for making the site better!



Laser Eye Surgery, Revisited 10 Years Later

Laser Dan Re:Uncertainty/fear? (550 comments)

I had it done in Japan, and instead of giving you Valium they have a young female nurse hold your hands :)

The actual procedure was interesting, but I was nervous about accidentally moving my eye to look at the interesting pattern of flashes (although I know it compensates for movement).

My vision was amaaazing for about a week, but then I started to get really dry eyes.
Now 3 years later my vision is apparently good in focus, but it is usually blurry because my eyes are so dry.
Drops only help for about 5sec.

So it is nice to be able to work etc without glasses/contacts, but at night my vision is terribly blurry unless I can keep my eyes moist.

Make sure you don't have any possible issue with dry eyes before you consider LASIK!

about 6 months ago

Mathematicians Push Back Against the NSA

Laser Dan Re:Mathematicians Have Always Had To Consider Ethi (233 comments)

It's not just mathematicians working for the NSA who are at fault; at this point, anyone working there is knowingly helping evil prevail. Anyone who doesn't quit is a scumbag.

If there was no risk of becoming homeless and starving, people would have a lot more choice in the matter...

about 9 months ago

Jimmy Wales To 'Holistic Healers': Prove Your Claims the Old-Fashioned Way

Laser Dan Re:You know what they call alternative medicine... (517 comments)

Of course the problem with placebos is that they essentially require lying to the patient. If you are honest and actually tell the patient "it's just a sugar pill" then it's not going to have any affect.

You would think that, but actually there was a study where the patents were TOLD that it was a placebo (and explained what a placebo is) and it still worked (!). I saw it in a documentary on youtube a week or so ago but can't find it now.

Basically, brains are wierd.

about 10 months ago

It's True: Some People Just Don't Like Music

Laser Dan Re:HEY (268 comments)

I can't comprehend how someone could not enjoy ANY music, music is the fundamental pre-cursor to language, not only is it deeply ingrained into humans but species as diverse as whales and grasshoppers use music to communicate with each other.

Interesting to know that 1-3% are like me.
I will clarify this for you.

I have zero interest in music. I have never bought (or pirated) a CD or mp3 in my life.
Why people are so obsessed with music I can't understand at all.
It's like how some people looove stamp collecting, I don't understand that obsession either.

It's not a DISlike of music, it's just no interest.
Sure some music has a good beat, or a catchy tune, and I won't complain if someone plays music, but I would never actually choose to play music myself.

Besides this I am pretty much the same as everyone else, I'm not autistic or anything.
I'm an engineer, with friends and a girlfriend, hobbies and a good job.
Music just isn't any more interesting to me than bird noises etc.

about a year ago

Ask Slashdot: How To Stay Fit In the Office?

Laser Dan Re:Excercise and diet (372 comments)

I use the stairs when going up to my office in the morning and at lunch.
If there are people there, I do my usual 2 steps at a time, fast pace but not enough to make people look at me funny.
If there's nobody around, I run up as fast as possible, then recover for a min at the top.

At first I couldn't make it all the way running, but I can get up the 6 floors in ~24 seconds now and can breathe normally enough after that people in the office don't notice. It's not that much, but better than nothing.

about 2 years ago

D&D Monster Study Proves Eyes Have It

Laser Dan Re:Eyes show emotion (196 comments)

It has been shown many times in studies that people are able to read a lot of emotion by looking at another person's eyes.

This is also the main reason most manga and anime authors prefer to draw big eyes. They're a much easier way to transmit emotions than body postures, allowing for a faster drawing process...

That reminds me of something interesting I noticed - in "western" countries the emoticons are focussed on the mouth, :) :( :p etc
But in Japan, they are mainly about the eyes, like ^_^ (others mangled by slashdot)

more than 2 years ago

Illegal Downloading Now a Crime In Japan With Increased Penalties

Laser Dan screw that! (286 comments)

What a ridiculously disproportionate penalty, I thought only the US was that screwed up.
I blame Sony.

I'm living in Japan, so lately I have been renting a "seedbox" in the Netherlands for $15/month.
I can download whatever I want to through the web interface, then copy it via sftp.
I'm sure solutions like this will start becoming a lot more common soon.

more than 2 years ago

Speed of Sound Is Too Slow for the Olympics

Laser Dan Excuses excuses (1 comments)

This guy reacted 300ms later than the others and he blames it on the speed of sound?
300ms at 340m/s is 102m, there's no way he was that far away from the other athletes.

more than 2 years ago

An Olympic Games For Enhanced Athletes?

Laser Dan Re:All Drug Olympics (245 comments)

Why shouldn't one be allowed to choose what they do to their body?

As long as there is no coercion to the individual ("do this or we send you and your family to the rape pits") and it truly is that individual's choice what they do to their body, I don't really care what an athlete does to themselves.

Maybe put restrictions - no modifications allowed until after the age of 18 and then after that they can consent to whatever - so that children aren't being damaged any more than they already are by being pushed to hyper-competitiveness.

Yeah, I bet countries like china would never even CONSIDER dosing kids from birth to get an advantage...

more than 2 years ago

Ask Slashdot: Hobbyist-Ready LCD Touch Panel For Embedded Projects?

Laser Dan 4dsystems (142 comments)

Try looking at http://www.4dsystems.com.au/

They sell touchscreens around that size with a controller that you can either program using a C-like language, or send commands to from an AVR etc.

more than 2 years ago

1Gbps Wireless Network Made With Red and Green Laser Pointers

Laser Dan Overhyped!! (157 comments)

I don't know why this is being hyped so much... from my brief look it seems pretty dodgy.
I'm not an expert in data transmission, but I have reviewed quite a few papers.

Two main points stand out:

1. They have two lasers of different wavelengths just so they can use the phrase "wavelength division multiplexing", but the lasers point at separate photodiodes! The lasers could be the same wavelength and it would make no difference.
Doing this adds nothing to their paper and lowers my impression of the research quality.

2. Their adaptive filter seems to require that the receivers already know the correct data in order to measure the amplitude/phase error and adapt.
Why would you need to transmit the data if it is already known at the receiver???

I would reject this paper.

more than 2 years ago

Surface-To-Air Missiles At London Olympics

Laser Dan Re:McOlympics (395 comments)

OK, that's not true, I stopped taking the Olympics seriously when Roy and HG got involved.

Roy and HG's coverage is the only one worth watching these days.

more than 2 years ago

Flying Robots Flip, Swarm and Move In Formation At UPenn

Laser Dan Re:Note the cameras, lights, and antennas. (122 comments)

Do you not realize that collision avoidance becomes rather more difficult when the things you're trying to avoid colliding with are themselves moving? They're not setting up a pattern to fly in, the computer is calculating trajectories for each robot such that they won't interfere with each other at any point in the future. A rather taller order.

What collision avoidance?
They are all externally controlled, and the controller knows their position to within a few mm due to the very expensive vicon system they are using.
All they are doing is moving along preplanned and precalculated trajectories.

As a robotics researcher I'm not really impressed.
External control and localisation removes 99% of of the difficulty of the problem.
It also makes this research useless for any actual real-world function, it's only good for fancy demos in their specially prepared room.
If they did that with only onboard sensors and control, THEN I would be impressed.

more than 2 years ago

Scientists Create World's First Atomic X-Ray Laser

Laser Dan Not like a standard laser (145 comments)

I wouldn't call this laser "the same manner as visible-light lasers" really, it lacks one of the fundamental features of a normal laser - self amplification via feedback from mirrors.
It sounds like this could be the _basis_ for a laser, as a pump source causes superluminescence, but without feedback it won't be particularly directional.
Perhaps if it can be triggered to start the avalanche at one end a directional burst could be achieved though, kind of like a nitrogen laser.

more than 2 years ago

Do Companies Punish Workers Who Take Vacations?

Laser Dan Re:South Korea (948 comments)

I work in Japan (Tokyo) as an engineer in a small company. I was worried about extreme hours and no holidays when I started, but it is actually OK.
Official hours are 9-6, and people actually start to leave around 6:30. The boss is indeed a 50 year old man, but he leaves around 7 (maybe cause he's not married).
People sit/sleep at their desks during the hour off for lunch, but nobody does any work unless something is really urgent.
I usually leave about 7-7:30, but I leave at 6 sometimes and it's fine.

Over the new year holidays most people took about a week off, but that's about it for the year besides public holidays. There is "golden week" too though, where there is a small gap between a bunch of public holidays, and most people take those off.

It may be different in large rigidly controlled companies though.

about 3 years ago

Approximately how speedy is your Internet connection?

Laser Dan Meanwhile in Japan... (367 comments)

100Mb/s dowload, no cap
100Mb/s upload, 30GB/day (yes day) cap
Cost is about US$50/month, for only a bit more 1Gbps is available but I thougt that was slightly excessive.
It's good to live in a civilised country!

about 3 years ago

JPMorgan Rolls Out (Another) FPGA Supercomputer

Laser Dan Re:FPGAs as coprocessors? (210 comments)

This story got me thinking that many of the tasks routinely executed on personal computers (perhaps cryptography, video decoding, and such) may benefit from including a FPGA in PCs to serve as a programmable coprocessor. Much like graphics-intensive software can come with shader code to offload processing to the GPU, couldn't a video codec or an implementation of SSL or whatever come with code that would allow an FPGA to do part of the work?

Xilinx (one of the two big FPGA companies) very recently released their "Zynq" family of combined CPU+FPGAs. They contain a dual core ARM Cortex-A9 running at 800 MHz and a pretty decent amount of 28nm FPGA logic, with interconnects between the two. That is basically what you are describing I think.

more than 3 years ago

JPMorgan Rolls Out (Another) FPGA Supercomputer

Laser Dan Re:too bad (210 comments)

If these algorithms are profitable they ultimately buy low and sell high, which is good for society. When you buy low, you're providing cash to those who need it most (therefore the willingness to sell low) and when you sell high, you provide the asset when it's needed most. Essentially, a profitable trader (computer or not) helps moderate markets by preventing them from going too low or too high, and pricing things correctly is important to society because resources are allocated by price. I know it's trendy to bash finance but it has an important function in society.

What you described is how trading SHOULD work, where a trader holds a certain stock for at least hours or days.
You are correct that this is good and stabilises things.

How it actually seems to happen these days is computers buy stocks on minor fluctuations, then sell them on another fluctuation a couple of microseconds later.
That doesn't seem to provide any useful function to me.

more than 3 years ago

The Mathematics of Lawn Mowing

Laser Dan Re:Give it a few tries and go with what's fastest (514 comments)

Believe it or not sometimes people are better at solving certain problems than computers. This is one of those fuzzy problems with lots of irregularities that a human is excellent at working out with just a little help from a stopwatch.

Actually this is a perfectly normal problem where the results you get out of a computer will depend a lot on how well you define the problem. If you define the shape of the lawn, the size of the cutter, and the turning characteristics of the mower accurately, I have little doubt that a computer can come up with a more optimal solution than a human (even if only by a small amount). A human with a stopwatch is unlikely to try more than about 15 different routes while a computer in simulation can try millions of routes in a short time.

The question is really "is it worth it". A human can easily come up with a decent route just by looking at the lawn, so it is probably not worth the time of making a simulation and running an optimisation to save 5% of the time unless you are a professional golf course mower.

more than 3 years ago



Ask Slashdot: The Search for the Ultimate Engineer's Pen

Laser Dan Laser Dan writes  |  more than 2 years ago

Laser Dan (707106) writes "I'm an engineer (robotics) who can't seem to find a pen that satisfies me.
Most of my writing is just temporary "thinking notes" on random bits of paper, like diagrams, flowcharts, equations etc, but pens always seem to have one or more of the following issues:
1. They write too thickly — I write very small, and when I start adding extra details to diagrams it gets even smaller. A line width of about 0.2-0.4mm would be good.
2. The ink bleeds, making the lines thick and unclear.
3. The ink is slow to dry or the tip grows blobs of ink, causing smudges everywhere.
4. The first line drawn is not fully dark, as the ink takes a short distance to get going.
5. The lines drawn are faint unless you press hard (I don't)

I have been given several fancy pens (Parker etc) over the years but they all suffered from problems 1, 3 (blobs), 4 and 5.
I'm considering trying a Fisher space pen, but it looks like even the fine cartridge writes rather thickly.

Have any fellow Slashdotters found their ultimate pen?"

Link to Original Source

How much ACTUAL work do you do in a day?

Laser Dan Laser Dan writes  |  about 6 years ago

Laser Dan (707106) writes "In a typical 8-hour working day, how many hours do you really concentrate for?

* Work??
* 0-1
* 1-2
* 2-4
* 4-6
* > 6
* CowboyNeal works while I sleep"


Laser Dan has no journal entries.

Slashdot Login

Need an Account?

Forgot your password?