Sunday, March 30, 2008
earth hour
This Saturday some idiots and newspeople asked me to turn off the lights for one hour, along with Sydney and some other big cities that were going to do the same thing. Images of people sitting at restaurant tables around a candle as the lights went off flashed around the TV screen all evening long. "Turn off the lights and use candles" seemed to be the message. Well, that's insultingly stupid. That's not an invitation to decrease pollution, but an invitation to return to the dark ages! Don't get me wrong, I hate pointless artificial lighting. I absolutely hate not being able to see the stars and other astronomical objects because of all the fucking lights. Who the hell needs lighting at 2 am in the night? That's a total waste of electricity and a fart in the face of all astronomers and stargazers everywhere. But candles? Let's take a look at the luminous efficiency of candles versus modern lighting. The humble incandescent light has a terrible efficiency of only 2.5%, because of all the thermal radiation it emits, only a small part is visible. The more advanced fluorescent gas-discharge lamp can reach 15%. LEDs are currently worse, contrary to popular belief. Low-pressure sodium vapor lamps can reach 27% efficiency, which is huge. They have an added advantage of being easily filtered out when doing astronomy, because their yellow color has a very narrow spectrum. Take a power station efficiency of let's say 10%, which is a very, very low estimate, stick an incandescent light bulb at its output and you get an overall efficiency of 0.25% from coal or whatever noxious fuel you're using to pure light. Now take a candle and burn it, releasing carbon dioxide, carbon monoxide, soot and useless heat into the atmosphere, get an efficiency of about 0.04% (so that's more than 5 times worse than the most inefficient coal-to-light technology in current use) and brag about how great an environmentalist you are. Then smell your farts and comment on their exquisite flavor. Then exchange farts with all your brain-dead environmentalist friends who don't know shit about physics, chemistry or biology and brag and lick each others' asses. And celebrate Earth Hour.
Wednesday, March 19, 2008
the drunken man problem
The Original Drunken Man Problem
A drunk man is standing next to a pole at moment t_0=0.
At each moment t_s,k = k * tau the man takes a step in a random direction.
Find the most probable distance between the man and his initial starting position at time t.
For simplicity assume a constant tau = 1 second and all steps equal to 1 metre.
Elaborating on the Problem
An inebriated individual stumbles out a bar at moment t_0=0.
At each t_s,k = k * tau the guy takes a step in a direction given by angle alpha.
Every p steps alpha changes to a random direction then remains constant.
p follows a Poisson distribution with lambda = 4.
The distance travelled during one step follows a normal distribution with mu = 0.5 m and sigma^2 = 0.5 m^2.
To complicate matters further, upon colliding with the bar wall a new alpha is selected.
Find the most probable distance travelled at time t.
Then assume a normal distribution for tau too.
A drunk man is standing next to a pole at moment t_0=0.
At each moment t_s,k = k * tau the man takes a step in a random direction.
Find the most probable distance between the man and his initial starting position at time t.
For simplicity assume a constant tau = 1 second and all steps equal to 1 metre.
Elaborating on the Problem
An inebriated individual stumbles out a bar at moment t_0=0.
At each t_s,k = k * tau the guy takes a step in a direction given by angle alpha.
Every p steps alpha changes to a random direction then remains constant.
p follows a Poisson distribution with lambda = 4.
The distance travelled during one step follows a normal distribution with mu = 0.5 m and sigma^2 = 0.5 m^2.
To complicate matters further, upon colliding with the bar wall a new alpha is selected.
Find the most probable distance travelled at time t.
Then assume a normal distribution for tau too.
Saturday, March 8, 2008
science fiction
"Captain, we've lost optical output in the converters in room 100!"
"My god! The molecular reactors cannot function without sustained input from room 100! The life support systems are in danger! Not to mention the crew being unable to perform their duty without proper environmental conditions in the waste dispoal facility!
"I agree, the situation is looking pretty grim. What should I do, Captain?"
"Quickly, energize the emission coils!"
"Coil temperature is reaching 3000 Kelvins, Sir."
"Good. Now decrease the converter frequency to get closer to resonance."
"Decreasing operating frequency 35%... The positive-coefficent thermistors are heating up. No-go, sir. The power controller has detected an overvoltage in the resonant circuit and is shutting down."
"Yellow alert! Everyone prepare for emergency biostasis in case of environmental failure. Officer, reset the controller, move the frequency back up and wait for the thermistors to cool down."
"Done. The emission coils are operational. Increasing field strength to 900 volts per meter."
"Are the atoms responding?"
"Yes, we've got arc ignition. The resonance point is dropping... Hold on, the plasma is getting unstable! It's oscillating chaotically on a subsonic frequency! I can't keep it going! It's out, we've got another overload!"
"Reconfigure the overload threshold to 120% and retry the ignition sequence with a 30% increase in the ionizing field."
"Yes sir. Heating up the emission coils... field is increasing... we've got ignition... no, the plasma column is not holding."
"Try again with 50% field increase for 5 seconds."
"Trying... the protection network cannot hold much longer with all that power coming from the resonant circuit! We've got to get that plasma to increase in density or we're dead!"
[Officer 2 enters command deck] "Captain, the life support systems have shut down! The bioreactor has run out of input material! We need the crew to start shitting NOW!"
[Officer 3] Yes, besides, I can't hold it in much longer! We need to get that damned toilet fixed!
"Red alert! Everyone to the stasis cells now! Prepare for immediate hibernation on my signal. Officer, increase average power to 175% and switch to discontinuous mode."
"The pulse capacitors won't tolerate 175% sir. That's way over their nominal rating! We risk losing the entire converter assembly!"
"I'm willing to take that risk, officer. Quickly, short-circuit the output divider! Decrease the feedback ratio in the boost converter! Adjust the inductive reactance! Lock on that phase! Enhance those FETs!"
"Disabling overload threshold... Increasing main voltage... Setting target frequencies... Yes, we've got constant output! Decreasing power to nominal... Plasma is holding Sir! We've got optical output!"
"Good job, officer! Cancel alert. Everyone report to room 100 in decreasing order of intestinal discomfort. Go get yourself a beer officer!"
"Thank you Captain!"
"Captain's log supplemental. With the optical converters in room 100 fixed, crew morale is better than ever and everything is back to normal. These happenings have delayed our mission to Sirius 5, so unfortunately we missed our chance to meet Ambassador Kuux. Ironically this might have come as a blessing to us, as we learned from a Karbazian subspace transmission that Atheist
terrorists suicide-bombed the Agnostic conference room where the meeting was taking place. They detonated 300 micrograms of superfluid qvadrilithium crystals using a modified antiselenium primer. Both are undetectable to Karbazian bosonic spectrometry scanners. We sent our deepest most sincere regrets to the people of Sirius 5, but we sure are glad our asses weren't fried in the blast. Thus life goes on aboard the Sputnik V, leaving one to wonder just how has humankind evolved over millenia from flesh-eating, spear-wielding top-of-the-foodchainers to space-travelling woosies who won't even take a goddamned shit if there's no light in the toilet."
"My god! The molecular reactors cannot function without sustained input from room 100! The life support systems are in danger! Not to mention the crew being unable to perform their duty without proper environmental conditions in the waste dispoal facility!
"I agree, the situation is looking pretty grim. What should I do, Captain?"
"Quickly, energize the emission coils!"
"Coil temperature is reaching 3000 Kelvins, Sir."
"Good. Now decrease the converter frequency to get closer to resonance."
"Decreasing operating frequency 35%... The positive-coefficent thermistors are heating up. No-go, sir. The power controller has detected an overvoltage in the resonant circuit and is shutting down."
"Yellow alert! Everyone prepare for emergency biostasis in case of environmental failure. Officer, reset the controller, move the frequency back up and wait for the thermistors to cool down."
"Done. The emission coils are operational. Increasing field strength to 900 volts per meter."
"Are the atoms responding?"
"Yes, we've got arc ignition. The resonance point is dropping... Hold on, the plasma is getting unstable! It's oscillating chaotically on a subsonic frequency! I can't keep it going! It's out, we've got another overload!"
"Reconfigure the overload threshold to 120% and retry the ignition sequence with a 30% increase in the ionizing field."
"Yes sir. Heating up the emission coils... field is increasing... we've got ignition... no, the plasma column is not holding."
"Try again with 50% field increase for 5 seconds."
"Trying... the protection network cannot hold much longer with all that power coming from the resonant circuit! We've got to get that plasma to increase in density or we're dead!"
[Officer 2 enters command deck] "Captain, the life support systems have shut down! The bioreactor has run out of input material! We need the crew to start shitting NOW!"
[Officer 3] Yes, besides, I can't hold it in much longer! We need to get that damned toilet fixed!
"Red alert! Everyone to the stasis cells now! Prepare for immediate hibernation on my signal. Officer, increase average power to 175% and switch to discontinuous mode."
"The pulse capacitors won't tolerate 175% sir. That's way over their nominal rating! We risk losing the entire converter assembly!"
"I'm willing to take that risk, officer. Quickly, short-circuit the output divider! Decrease the feedback ratio in the boost converter! Adjust the inductive reactance! Lock on that phase! Enhance those FETs!"
"Disabling overload threshold... Increasing main voltage... Setting target frequencies... Yes, we've got constant output! Decreasing power to nominal... Plasma is holding Sir! We've got optical output!"
"Good job, officer! Cancel alert. Everyone report to room 100 in decreasing order of intestinal discomfort. Go get yourself a beer officer!"
"Thank you Captain!"
"Captain's log supplemental. With the optical converters in room 100 fixed, crew morale is better than ever and everything is back to normal. These happenings have delayed our mission to Sirius 5, so unfortunately we missed our chance to meet Ambassador Kuux. Ironically this might have come as a blessing to us, as we learned from a Karbazian subspace transmission that Atheist
terrorists suicide-bombed the Agnostic conference room where the meeting was taking place. They detonated 300 micrograms of superfluid qvadrilithium crystals using a modified antiselenium primer. Both are undetectable to Karbazian bosonic spectrometry scanners. We sent our deepest most sincere regrets to the people of Sirius 5, but we sure are glad our asses weren't fried in the blast. Thus life goes on aboard the Sputnik V, leaving one to wonder just how has humankind evolved over millenia from flesh-eating, spear-wielding top-of-the-foodchainers to space-travelling woosies who won't even take a goddamned shit if there's no light in the toilet."
Wednesday, March 5, 2008
You will not
(spam me)
an essay* to ruin your day :D
*based on a true story.
You will not advertise anything I might not be interested in when sending me e-mail. I hate spam.
You will not use big fonts and bright colors for it. I hate spam.
You will not send me mass instant messages. I hate spam. Each message incurs a 3-point penalty with a 2-day exponential decay constant. 10 points and you get banned. No questions asked.
You are allowed to do whatever you want in your personal space: the status text.
But only if it's not scrolling or otherwise updating every second, flooding me with useless packets. I hate bandwith-munching spam. You get banned. No questions asked.
You will not post pictures when your comment on my web pages. They (a) will probably ruin the color scheme and (b) will almost certainly ruin the layout, because Web 2.0 sucks and people writing Web 2.0 CMSes and layout templates don't care to think of stuff like: hey, what if some guy posts a 1000-pixel-wide image here? I hate web sissies. And spam.
You will not send me animated xmas e-cards lifted from the web, chainletters, pictures of dogs or bunnies or whatever, jokes (I hate bad jokes) or anything else. I hate everything, and spam. You get banned.
You will not send me docx files.
You will not talk to me.
You will not look at me.
You will not talk about me.
You will not think of me.
You will pretend I do not exist.
Or else.
an essay* to ruin your day :D
*based on a true story.
You will not advertise anything I might not be interested in when sending me e-mail. I hate spam.
You will not use big fonts and bright colors for it. I hate spam.
You will not send me mass instant messages. I hate spam. Each message incurs a 3-point penalty with a 2-day exponential decay constant. 10 points and you get banned. No questions asked.
You are allowed to do whatever you want in your personal space: the status text.
But only if it's not scrolling or otherwise updating every second, flooding me with useless packets. I hate bandwith-munching spam. You get banned. No questions asked.
You will not post pictures when your comment on my web pages. They (a) will probably ruin the color scheme and (b) will almost certainly ruin the layout, because Web 2.0 sucks and people writing Web 2.0 CMSes and layout templates don't care to think of stuff like: hey, what if some guy posts a 1000-pixel-wide image here? I hate web sissies. And spam.
You will not send me animated xmas e-cards lifted from the web, chainletters, pictures of dogs or bunnies or whatever, jokes (I hate bad jokes) or anything else. I hate everything, and spam. You get banned.
You will not send me docx files.
You will not talk to me.
You will not look at me.
You will not talk about me.
You will not think of me.
You will pretend I do not exist.
Or else.
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