In case you were wondering whether pornoscanners are harder on the vast majority of innocent, non-terrorist fliers, or the minuscule minority of terrorists, wonder no more. From Leon Kaufman and Joseph W. Carlson's "An evaluation of airport x-ray backscatter units based on image characteristics," published in the Journal of Transportation Security:
The penetration not only distributes exposure throughout the body (this affecting the calculation of effective dose, which comprises a sum over all organs), but tends to diffuse the effects caused by contraband materials. Images can be made at low entrance exposures, but of very poor spatial resolution and S/N. The calculated signal excursions at high kilovoltage are so small as to make it doubtful that at any reasonable exposure levels density differences will be noticeable unless the contraband is packed thickly and with hard edges. Although the excursions are larger at low kilovoltage, they are still small and in the noise of the device's operational limits. The eye is a good signal averager at certain spatial frequencies, but it is doubtful that an operator can be trained to detect these differences unless the material is hard-edged, not too large and regular- shaped. Anatomic features and benign objects add structured noise that interferes with signal averaging. Figure 18 shows a widely-distributed backscatter image. On the left is a complete view of her torso, on the right, a section has been blacked out. While the breasts are easily recognized at right, without some prior knowledge of the subject, it would be hard to distinguish the increase of intensity in the superior part of her breasts from the natural gradients of the image.
It is very likely that a large (15-20 cm in diameter), irregularly-shaped, cm-thick pancake with beveled edges, taped to the abdomen, would be invisible to this technology, ironically, because of its large volume, since it is easily confused with normal anatomy. Thus, a third of a kilo of PETN, easily picked up in a competent pat down, would be missed by backscatter "high technology". Forty grams of PETN, a purportedly dangerous amount, would fit in a 1.25 mm-thick pancake of the dimensions simulated here and be virtually invisible. Packed in a compact mode, say, a 1 cm×4 cm×5 cm brick, it would be detected.http://www.boingboing.net/2010/12/11/pornoscanners-trivia.htmlBut Michael
Jerkoff Chertoff wants you to know he does appreciate how your tax dollars are going to make him and his business associates rich anyway, and no, he never did understand this strange concept known as "conflict of interest".
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