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Comment Uh... summary? (Score 5, Insightful) 172

Article:
The operator of the crippled Fukushima Daiichi nuclear plant said it is studying whether the facility's reactors were damaged in the March 11 earthquake even before the massive tsunami that followed cut off power and sent the reactors into crisis.
Kyodo news agency quoted an unnamed source at the utility on Sunday as saying that the No. 1 reactor might have suffered structural damage in the earthquake that caused a release of radiation separate from the tsunami.
Summary:
Apparently, the earthquake had caused a crack in the containment vessel.

I'm not sure how the summary writer came to that conclusion... Shouldn't we wait for an actual report/finding before stating that?

Comment Port cities? (Score 3, Interesting) 125

The companies used for this fraud include the name of a Chinese port city in their official name. These cities
include: Raohe, Fuyuan, Jixi City, Xunke, Tongjiang, and Dongning.

Odd that they'd use the term "port city", as these don't sound like major transportation hubs. What's interesting is that all these places they've named are actually places on or near the border of Russia and China, in Heilongjiang Province.

Comment Re:please, enough horseshit (Score 2) 411

I don't know where New Scientist got their 1490 number, but the IAEA report on Chernobyl (http://www-pub.iaea.org/MTCD/publications/PDF/Pub1239_web.pdf) cited by Wikipedia gives an upper tier of 1480+ kBq/m^2 of cesium-137, except that 3100 km^2 of land in Russia, Ukraine and Belarus had at least that level of contamination. If you look at the total area at 555+ kBq/m^2 of cesium-137, you get 10300 km^2 of land which had at least that level of contamination. You'd need a circle with a radius of ~57 km to contain that much land.

Since 18 March, MEXT has repeatedly found caesium levels above 550 kBq/m2 in an area some 45 kilometres wide lying 30 to 50 kilometres north-west of the plant.

The wording here is kind of weird. Why are they using a single length to describe area? Furthermore, does "repeatedly found caesium levels above 550 kBq/m^2" mean that the entire area has that level of radioactivity or that simply they measured it in a few places and got high readings? The New Scientist article then gives high peak rates like 6400 kBq/m^2 of cesium, but fail to provide a comparison with Chernobyl. And to finish it off, they move onto talking about a totally different isotope (iodine-131). Becquerels measure the number of decay events per second, so comparing becquerel readings between two different isotopes is kind of pointless -- it doesn't compare the amount of energy being released.

Comment Color changing is the exception! (Score 4, Interesting) 31

There's nothing that requires a hologram to change colors as you change the viewing angle; it's just that there are many different techniques for generating holograms and the rainbow hologram happens to have been adopted widely in the commercial regime. Classic holograms were monochrome and required coherent illumination to see. The rainbow hologram is nice in that you can see it under white light, but suffers from color issues (obviously) and also only presents a three-dimensional view along one axis (try tilting your VISA card 90 degrees next time and the eagle should appear flat). I don't know if the exhibit is still there or not, but the MIT Museum in Cambridge had a really nice hologram exhibit with lots of different holograms. A bunch of them were full color and didn't have that rainbow effect.

This article does make me more curious about surface plasmons, however, since I hear that mentioned a lot nowadays and don't have a very good understanding of them.

Comment Re:I don't buy it (Score 2) 176

Just a nitpick, but...

  • Increasing the number of megapixels while keeping everything else the same does not change the amount of light the sensor collects, although each individual pixel gets less light.
  • Increasing or decreasing the fill-factor or changing the total sensor size does.
  • In low light situations, statistics of the intensity of light should be Poisson, which means that 4 pixels at 1/4 the area, when averaged together, should result in the same amount of SNR, assuming relatively small read noise, which should be dominated by the Poisson shot noise in this situation.
  • Thus, the only downside of having just more pixels on a sensor if everything else was equal (note that fill factor of pixels would probably be different between different sensors) is that there's now a lot more bandwidth coming out of the sensor, which could be an issue with power efficiency. This could possibly be mitigated by reducing the bit depth on each individual pixel, if you assume there's going to be more noise.
  • One upside is that if the pixel size is smaller than the diffraction spot size, then the relative size of your Bayer mosaic should make demosaicing easier.
  • To summarize... if you had more pixels in the same sized sensor and can deal with the extra bandwidth, then you should be able to, in the worst case, downsample to achieve similar or higher performance compared to what you had before.

Comment Re:People get motion sick. (Score 1) 281

If I remember correctly, one of the issues with current three-dimensional displays is that there's a disparity between vergence and accomodation in the eye. That is, normally, you point your eyes inwards to look at something closer, and you focus your lens closer as well. With 3D displays, what happens is that you have to focus at a different distance (i.e. where the actual display is) than what your eyes are verging on (i.e. the apparent depth of the image)... I guess you'll get used to it when you lose accomodation in your eyes as you age... :p

Comment Why not just sell fully uncompressed audio? (Score 1) 550

You know... FLAC doesn't actually compress down from WAV all that much. Given current storage sizes, why not simply just sell fully uncompressed audio files? You can use FLAC or whatever as the transmission medium and/or storage server-side to be less of a bandwidth burden, but the user should just see an incoming WAV file, etc. that he can do whatever he wants with...

Personally, I rip all my CDs to --preset-extreme MP3 to listen, since I can just pull out my CD if I really needed a bit-perfect copy (e.g. for voice track extraction).

Comment Re:Remember (Score 3, Informative) 199

Disclaimer: I am not very well versed in statistics and have only just read the Wikipedia article on Instrumental variables.

On page 14, the report discusses the model they use, which is a linear system of the log of the four variables they're trying to find relationships between. They then discuss 4 instrumental variables as well as two dozen or so dummy variables that describe aspects of the actual show, like when it is aired on TV, whether they have related drama CDs, net broadcasts, whether the anime was an original work or based on manga, novels, games, etc., who the target audience was and how many regions the show have been broadcast in. Table 3 has the full list, and also includes what I assume to be slopes in log-log space from their analysis as well as a "t" factor for which I'm not sure about. The four main instrumental (non-dummy) variables are: DVD price (number of thousands of yen per episode, how long a video on YouTube persists ... while the series is airing, within 1 month of that particular episode airing, and after the series is finished airing).

Table 4 is a chart highlighting that there is a negative correlation with DVD price and DVD sales, but a positive correlation of DVD price and YouTube views. There were also positive correlations between how long a video managed to stay on YouTube after airing of the TV show has been completed and DVD sales, rentals and YouTube views, but a negative correlation with Winny downloads.

According to Wikipedia, use of instrumental variables is one way to see if there is actual causation between two variables. However, I'll leave it to someone more well-versed in the subject to see if the report is accurate or not.

Comment *not* immediate (Score 3, Insightful) 58

Here's the relevant passage from the article with the juicy bits:

We acquired X-ray microscope images of these vitrified mammalian cells at tilt angles from 60 to +60 in increments of 1 at a pixel size of either 9.8 nm (25-nm zone plate objective) or 15.6 nm (40-nm zone plate objective). Exposure times for each tilt angle were 224 s. The total X-ray exposure (~109 Gy) produced negligible radiation damage, as we detected no difference in image quality between images acquired at the beginning and end of the tilt series (Supplementary Fig. 3). We processed the images using a reciprocal space algorithm11 to generate a 3D tomogram composed of cubic voxels whose side lengths were either 9.8 nm (25-nm zone plate objective) or 15.6 nm (40-nm zone plate objective).

So they took 121 x-ray images of the specimen, with each image taking 2-24 seconds, and then stitched them together using a tomography technique to obtain their 3D volume. It's certainly faster than a few weeks, but this is not what I would consider "immediate". The article also points out that poor cryopreservation led to some artifacts and that the resolution in this technique was still not as good as the TEM; not having an entire 180 degree rotation of the object led to artifacts as well:

We did not detect some structures by X-ray tomography that we detected by TEM, such as ribosomes and the double membrane of the mitochondrial cristae. These probably fall below the current resolution limit (see below). An additional limitation was the restricted tilt angle range (±60) used in these experiments. This led to poorer resolution in the z dimension, as indicated by a distortion in the 3D shape of some organelles, which appeared more cylindrical in x-z views (Fig. 3b) as well as an inability to obtain face-on views of the nuclear pores (data not shown) or follow the complete circumference of the nuclear membrane (Supplementary Fig. 5b).

Comment Re:Modern Women (Score 2, Informative) 305

So, you're saying she sounds like capsule and perfume? :p

On a more serious note, a (paid) update to Hatsune Miku gives her 6 additional voicing styles. I find that one of them might be able to sound somewhat like a real person if programmed well. Megpoid, using the same Yamaha sound engine, sounds a lot more realistic than the other Vocaloid2 products, and also doesn't require as much tweaking.

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