I made it to post 100. I think I have been posting too much, so I'm going to roll back my expectations for myself to four posts a month, with one of them a big post. Otherwise I think I will end up posting too many secondary links.
Things that I've learned:
- writing long posts is hard, but it has been good practice for my writing abilities
- most random links I still email to one person only. It has been tempting to post them to the blog, but I am happier when I don't
- comments are really rewarding, I now find myself leaving comments at other blogs (though I only rarely post a link back to my own).
- there was a lot to say about my big move at first, but I don't have much to say anymore
- I still have a few mementos ("I'll write about this later") that I haven't gotten around to researching. I thought I would find out about these things, but they haven't sprung up in conversation
- I now schedule a lot of my posts rather than write them on the spot.
2009-02-25
2009-02-24
Some Ugly Truths about Human Trafficking
The UN's Office on Drugs and Crime released its annual Global Report on Trafficking in Persons a few weeks ago.
The Dutch fared poorly. A uniform comparison across countries is difficult since reported data varies by country. Countries provide some sub-set of people prosecuted, convicted, investigated or suspected of trafficking. A quick look through the data suggests that the Netherlands is either much better at prosecuting people, or that human trafficking is a problem for the Dutch. Conviction and prosecution rates per capita in Holland were eight times as high as the UK. The UK has roughly four times the population of the Netherlands, but the UK prosecuted and convicted less than half the number of people that Holland did.
Another interesting anomaly was the gender breakdown of convictions in Eastern Europe. In Latvia, for example, women are convicted of less than 10% of all crimes, but they account for over half of human trafficking convictions.
Anyways, the big picture is very dim. Sometimes it is easy to forget that it is 2009.
The Dutch fared poorly. A uniform comparison across countries is difficult since reported data varies by country. Countries provide some sub-set of people prosecuted, convicted, investigated or suspected of trafficking. A quick look through the data suggests that the Netherlands is either much better at prosecuting people, or that human trafficking is a problem for the Dutch. Conviction and prosecution rates per capita in Holland were eight times as high as the UK. The UK has roughly four times the population of the Netherlands, but the UK prosecuted and convicted less than half the number of people that Holland did.
Another interesting anomaly was the gender breakdown of convictions in Eastern Europe. In Latvia, for example, women are convicted of less than 10% of all crimes, but they account for over half of human trafficking convictions.
Anyways, the big picture is very dim. Sometimes it is easy to forget that it is 2009.
2009-02-22
Reddit Round-Up: Photoshop, Gender Biases when Rating Teachers, and Nuclear Reactors
Some interesting photoshop examples (EDIT on 2009-06-09: link is borked, my apologies). Who knows if they're real - maybe they were reverse photoshopped?
Apparently high school students like male physics teachers more, even when the numbers say something else.
Iran is starting computer tests for its budding nuclear reactor at Bushehr.
Apparently high school students like male physics teachers more, even when the numbers say something else.
Iran is starting computer tests for its budding nuclear reactor at Bushehr.
2009-02-20
On Dirty Bombs and Construction Sites
Last week I got to play around with dangerous radiation, which was fun. But what was even better was talking to the people who work with the radiation. Apparently the Swiss government has a radiation "SWAT" team. I talked with a guy who was on the team about what they did, and he told me some crazy tales.
He said that he was routinely called to construction sites to deal with radiation problems. Apparently radioactive materials are commonly used on construction sites, especially in equipment that surveys the ground (sends waves into the ground and reads back the results). Bulldozers will sometimes accidentally drive over this equipment and expose the radiation source(s).
He told me the horror story of a factory worker in Chile who picked up an iridium source. Old factories use radiation sources for a variety of things, including flow meters, density sensors, and heating of all things! The source looked like a pen, and the worker picked it up. He tossed it from hand to hand (because it was so hot), and then put it in his back pocket.
At this point my colleague's story diverges from the internet. According to the IAEA, the worker showed the source to a few other people before some of them started to be sick. According to my colleague, the worker walked into a cafeteria and dosimeters of workers started going crazy.
They flew the worker to a French military hospital and immediately amputated a giant sphere (~10 cm diameter) of flesh from his butt, close to where he had the source. The French doctors used stem cells to treat him, and managed to save his life.
It was pretty fun to shot the breeze with this guy, especially on the subjects of dirty bombs and terrorism. We talked about how the current generation of bomb detectors at the borders was absurd. Shielding a uranium bomb from the border detectors or sneaking a bomb through under a common false alarm condition (hide the bomb in a truck with kitty litter and old electronics like CRTs) are not difficult feats of engineering. We talked about dirty bombs, and whether Cs-137 or Co-60 would make better "dirt".
The crazy part of my work with radiation is that now I feel a lot safer at Delft's nuclear facility than at a random construction site. If something horrible did happen, the people at nuclear facilities have the know-how to clean it up. Also, there are stringent regulations at the nuclear / radiation facilities I have been to.
If you need further proof of safety, just look at the moat at Delft's facility. Sadly the architect couldn't convince the university to spring for the draw-bridge option.
He said that he was routinely called to construction sites to deal with radiation problems. Apparently radioactive materials are commonly used on construction sites, especially in equipment that surveys the ground (sends waves into the ground and reads back the results). Bulldozers will sometimes accidentally drive over this equipment and expose the radiation source(s).
He told me the horror story of a factory worker in Chile who picked up an iridium source. Old factories use radiation sources for a variety of things, including flow meters, density sensors, and heating of all things! The source looked like a pen, and the worker picked it up. He tossed it from hand to hand (because it was so hot), and then put it in his back pocket.
At this point my colleague's story diverges from the internet. According to the IAEA, the worker showed the source to a few other people before some of them started to be sick. According to my colleague, the worker walked into a cafeteria and dosimeters of workers started going crazy.
They flew the worker to a French military hospital and immediately amputated a giant sphere (~10 cm diameter) of flesh from his butt, close to where he had the source. The French doctors used stem cells to treat him, and managed to save his life.
It was pretty fun to shot the breeze with this guy, especially on the subjects of dirty bombs and terrorism. We talked about how the current generation of bomb detectors at the borders was absurd. Shielding a uranium bomb from the border detectors or sneaking a bomb through under a common false alarm condition (hide the bomb in a truck with kitty litter and old electronics like CRTs) are not difficult feats of engineering. We talked about dirty bombs, and whether Cs-137 or Co-60 would make better "dirt".
The crazy part of my work with radiation is that now I feel a lot safer at Delft's nuclear facility than at a random construction site. If something horrible did happen, the people at nuclear facilities have the know-how to clean it up. Also, there are stringent regulations at the nuclear / radiation facilities I have been to.
If you need further proof of safety, just look at the moat at Delft's facility. Sadly the architect couldn't convince the university to spring for the draw-bridge option.
2009-02-16
Don't Rub Beryllium Tools on your Skin
Cool fact: beryllium scissors, screwdrivers and pliers are used near MRI machines since the metal doesn't react (noticeably) to the magnetic field. I looked into getting some Be-tools, but apparently the metal is highly toxic and the tool sets are really expensive. $4,000 a tool-set expensive. Weak.
2009-02-13
No French Hamsters?
I was wandering around Lausanne and saw an odd movie poster for "Volt", the translated version of the American movie "Bolt". I suppose hamsters are American, with their obesity and refusal to translate things:
I'd Focus Her Ion Beam
Over the past week I've been doing a bunch of stuff in Lausanne, Switzerland. Unfortunately most of it failed. Sigh.
But I got to play around with EPFL's focused ion beam (FIB) for another project. EPFL's FIB is a combination of an electron microscope, a platinum depositor, and a Gallium microscope/etcher.
What was I doing with the FIB? I was fixing integrated circuits. One fixes circuits by etching away parts of the chip (the equivalent of cutting a line), and then using the platinum depositor to short other lines. This re-routes the signals, and fixes your design mistake. The etching is performed by the Ga microscope. Normally the number of Ga ions does not drastically effect the surface, but if you use a lot of Ga ions, then you can etch away parts of the chip. The etching occurs even when you're using the Ga microscope as a microscope - in other words, if you use the microscope for too long, you etch away the entire surface off the chip. As far as I know electron microscopes don't have sufficient energy to etch the surface, but it wouldn't surprise me if a high-energy electron microscope could also etch a chip.
The etching is mechanical, so the etched atoms spray above the chip. The etching is performed in a vacuum so that these atoms don't (hopefully don't) end up on the surface of the chip and interfere with surface electronics.
Anyways, that is enough theory. One of the other groups has been having trouble properly simulating a design, so they wanted to use the FIB at EPFL to test something. Since I was going to be in Switzerland, I oversaw the FIB use.
A high level overview is that we needed to re-route a grounded signal. A line was shorted to ground, and we needed to short it to the power rail instead. I'll call the line we're working with line "Q". First, we had to cut line Q. Next, we exposed line Q a distance away. We then exposed the power line. Finally, we shorted line Q's exposure to the power line's exposure. Well, at least we think we did. No one has tested the chips yet.
You might ask yourself why we didn't just short the power line to line Q's cut directly. The platinum (Pt) deposition isn't easily controlled (we're working with nanometers of distance), and we would have risked shorting both sides of the cut to the power rail if we tried to short the power rail to Q at the cut. Risking a power rail to ground short is bad. Very bad.
First up, we cut line Q. Here is a picture:
The hole near the bottom-middle of the L-shaped objects is the cut. I believe the L-shaped and square objects are support patterns on the surface of the chip. Silicon foundries yell at you if you don't use a minimum amount of metal for each layer. Something like a third of the layer must be used. I'm not sure if it is an issue with the lower layers supporting the upper layers or the implant process, but either way it is easier to put patterns on the un-used parts of the chip than having the foundry yell at you. You can see some lower layer patterns in the cut, they're the twelve or so little dots. We use different patterns for different layers, ostensibly for better chip support. Or something. I'm not 100% sure about reasons behind the patterns, so take everything I saw about them with a grain of salt.
Anyways, next up we needed to expose the Q line farther down:
I've circled the exposed Q line, which runs vertically. Ga ions interact differently with conductors, and the results is that conductors show up more brightly in pictures from this Ga microscope. If this pictures doesn't convince you that we hit the line, I wasn't convinced either. Due to the support patterns, the Ga ions etch through the chip at different speeds, and it was impossible to get a picture-perfect exposure. Also, please keep in mind that the line is about 500 nm wide. This was the best result of several failed attempts on previous chips.
Similarly, we found the power supply line, which ran horizontally:
Finally, we used the Pt depositor to short the two:
As you can see, some of the surface material was sucked into the hole when we deposited the Pt bypass. I don't know if the material melted or was pulled down from a mechanical force.
As I previously said, we haven't tested these chips. Even if they don't work, it was a very interesting event to see. Please feel free to ask any questions, though I'm not sure I'll be able to answer them. Single bypass surgery on integrated circuits isn't my specialty.
But I got to play around with EPFL's focused ion beam (FIB) for another project. EPFL's FIB is a combination of an electron microscope, a platinum depositor, and a Gallium microscope/etcher.
What was I doing with the FIB? I was fixing integrated circuits. One fixes circuits by etching away parts of the chip (the equivalent of cutting a line), and then using the platinum depositor to short other lines. This re-routes the signals, and fixes your design mistake. The etching is performed by the Ga microscope. Normally the number of Ga ions does not drastically effect the surface, but if you use a lot of Ga ions, then you can etch away parts of the chip. The etching occurs even when you're using the Ga microscope as a microscope - in other words, if you use the microscope for too long, you etch away the entire surface off the chip. As far as I know electron microscopes don't have sufficient energy to etch the surface, but it wouldn't surprise me if a high-energy electron microscope could also etch a chip.
The etching is mechanical, so the etched atoms spray above the chip. The etching is performed in a vacuum so that these atoms don't (hopefully don't) end up on the surface of the chip and interfere with surface electronics.
Anyways, that is enough theory. One of the other groups has been having trouble properly simulating a design, so they wanted to use the FIB at EPFL to test something. Since I was going to be in Switzerland, I oversaw the FIB use.
A high level overview is that we needed to re-route a grounded signal. A line was shorted to ground, and we needed to short it to the power rail instead. I'll call the line we're working with line "Q". First, we had to cut line Q. Next, we exposed line Q a distance away. We then exposed the power line. Finally, we shorted line Q's exposure to the power line's exposure. Well, at least we think we did. No one has tested the chips yet.
You might ask yourself why we didn't just short the power line to line Q's cut directly. The platinum (Pt) deposition isn't easily controlled (we're working with nanometers of distance), and we would have risked shorting both sides of the cut to the power rail if we tried to short the power rail to Q at the cut. Risking a power rail to ground short is bad. Very bad.
First up, we cut line Q. Here is a picture:
The hole near the bottom-middle of the L-shaped objects is the cut. I believe the L-shaped and square objects are support patterns on the surface of the chip. Silicon foundries yell at you if you don't use a minimum amount of metal for each layer. Something like a third of the layer must be used. I'm not sure if it is an issue with the lower layers supporting the upper layers or the implant process, but either way it is easier to put patterns on the un-used parts of the chip than having the foundry yell at you. You can see some lower layer patterns in the cut, they're the twelve or so little dots. We use different patterns for different layers, ostensibly for better chip support. Or something. I'm not 100% sure about reasons behind the patterns, so take everything I saw about them with a grain of salt.
Anyways, next up we needed to expose the Q line farther down:
I've circled the exposed Q line, which runs vertically. Ga ions interact differently with conductors, and the results is that conductors show up more brightly in pictures from this Ga microscope. If this pictures doesn't convince you that we hit the line, I wasn't convinced either. Due to the support patterns, the Ga ions etch through the chip at different speeds, and it was impossible to get a picture-perfect exposure. Also, please keep in mind that the line is about 500 nm wide. This was the best result of several failed attempts on previous chips.
Similarly, we found the power supply line, which ran horizontally:
Finally, we used the Pt depositor to short the two:
As you can see, some of the surface material was sucked into the hole when we deposited the Pt bypass. I don't know if the material melted or was pulled down from a mechanical force.
As I previously said, we haven't tested these chips. Even if they don't work, it was a very interesting event to see. Please feel free to ask any questions, though I'm not sure I'll be able to answer them. Single bypass surgery on integrated circuits isn't my specialty.
2009-02-10
Things Going "sssshhhom" in the Middle of the Day
Sometimes, when I'm away on a trip, I log into my workstation and eject / retract the CD tray. Just to mess with my office-mates.
I'd ding the terminal bell, but I don't want to over do it.
# eject
# eject -t
I'd ding the terminal bell, but I don't want to over do it.
2009-02-07
2009-02-05
On a Few Things Sewage
The city of Oslo plans to run 200 of its buses on biomethane created from sewage. If this sounds interesting to you, I suggest you check out Rose George's book, The Big Necessity. In one of its chapters, the book goes over a similar use of sewage in China. The Chinese use "digesters" to create biomethane from pig and human excrement. Farmers use the biomethane for cooking and heating, and use the processed manure as fertilizer. Previously the farmers had spread the manure directly onto their crops, spreading disease. During the processing stage, the pathogens are partially broken down and the disease risk is mitigated. Not only does the digester create methane to heat homes, it also creates safer fertilizer for crops. The costs are the one-time construction time and materials of the digester, along with the recurring human cost of running the digester.
Footnote: The biogas link is via /. via EarthFirst via WorldChanging via IWA. Perhaps the blogosphere needs to come up with better linking customs.
Footnote: The biogas link is via /. via EarthFirst via WorldChanging via IWA. Perhaps the blogosphere needs to come up with better linking customs.
2009-02-02
Quick Hits: Blast from the Past
At lunch today I mentioned the bizarre, Japanese balloon attacks on the American homeland during WWII. My Japanese colleague was unaware of them. Quote:
Though I dislike censorship, I think the evidence supported it in 1945.
Improbable though it may sound, from late 1944 through the spring of 1945, the Japanese launched more than 9,000 balloons from their nation's eastern shores...One balloon, for example, managed to cut through power lines leading from the Bonneville Dam on the Columbia River. A resulting power outage that was quickly restored may sound insignificant; however, that particular dam provided power to a factory in Hanford, Wash., which was secretly manufacturing plutonium for use in the atomic bombs destined for Japan.
Though I dislike censorship, I think the evidence supported it in 1945.
2009-02-01
Quick Hit: Massachusetts and Coddling Young'uns
Requiring a helmet while sledding is one of the dumbest ideas I've heard:
Seriously Massachusetts? Should we all wear bright orange jackets when crossing the street so cars see us, too?
... some people are pushing for a law that would require children, 12 and younger, to wear a helmet while sledding ... Panagiotakos argues that a state that requires children to wear helmets while bicycling - as Massachusetts does - should mandate the same equipment for sledding.
Seriously Massachusetts? Should we all wear bright orange jackets when crossing the street so cars see us, too?
Daylight
As I go slowly insane while analyzing data, I find myself wanting to analyze more data. Thanks to the efforts of the U.S. military, I can fulfill these caprices. I have concocted a few graphs to illustrate daylight in the different places where I've lived. These graphs do not include the effects of weather. Note that southern CT is not included, as it has roughly the same longitude as Cedar Rapids, IA.
First up is a graph of minutes of daylight per day versus time of year.
Delft gets over 1,000 minutes of daylight per day in the middle of the summer. Or, rather, the cloud-layer over Delft gets this daylight. Boston and Cedar Rapids only have small differences in daylight per day.
I was wondering how much less daylight Delft gets per year than Iowa, and to my surprise, Delft gets more daylight!
The second graph is a zoom of the previous graph. As you can see, Delft gets roughly one more day of daylight each year than Cedar Rapids and Boston.
I am looking forward to the days following the Equinox here. One thousand minutes of daylight. Sounds like a novel.
First up is a graph of minutes of daylight per day versus time of year.
Delft gets over 1,000 minutes of daylight per day in the middle of the summer. Or, rather, the cloud-layer over Delft gets this daylight. Boston and Cedar Rapids only have small differences in daylight per day.
I was wondering how much less daylight Delft gets per year than Iowa, and to my surprise, Delft gets more daylight!
The second graph is a zoom of the previous graph. As you can see, Delft gets roughly one more day of daylight each year than Cedar Rapids and Boston.
I am looking forward to the days following the Equinox here. One thousand minutes of daylight. Sounds like a novel.
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