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+ - Another Healthcare Radiation Overdose Problem->

Submitted by bezenek
bezenek (958723) writes "The New York Times has an article about a linear accelerator-driven pinpoint radiation device (this is not a radiation-source driven device, or Gamma Knife) which radiated four people because of incorrectly placed beam-blocking plates. No one has determined how the error occurred, but it may have been avoided by more careful operators or a more carefully engineered system. The company that makes the device had warned users about the possibility of the treatment data being garbled during transfer between multiple computing devices in the treatment pipeline.

I wonder if we will decide to require certification of software engineers the way we do with engineers who design bridges and electrical systems. It will not eliminate all problems like this, but at least we will have some control over who builds these lifesaving and sometimes life-taking devices.ex"

Link to Original Source

Comment: Why hire real doctors? (Score 2, Insightful) 483

by bezenek (#33700986) Attached to: Why Warriors, Not Geeks, Run US Cyber Command Posts

Why do we bother to hire real doctors to work in medical units? Aren't they going to have trouble figuring out whether or not someone was shot? Shouldn't we train military people to operate on wounded soldiers?

Sheesh! This is yet another case of the average person thinking technical people spend years learning what they know and somehow they are not valuable experts the way other specialists are.


Comment: Re:Use your local ham radio club (Score 4, Informative) 499

by bezenek (#32726972) Attached to: Tracking Down Wi-Fi Interference?

A quick clarification: The top of the AM dial (around 1500) is 1500kHz, or 1.5MHz. This is not close to the 2400MHz, or 2.4GHz at which WiFi operates.

The ability to identify the origin of the interference using an AM radio relies on the fact that the interference is produced from a source (often an electrical spark or arc) which generates RF noise on the entire spectrum. The spark plugs in car engines are a notorious cause of this sort of interference. If the spark plug wiring in a car is not shielded properly, you will hear a whining sound on an AM radio which changes pitch as the engine RPM changes.

AM radios happen to be easy to find and are very good at "hearing" the noise produced by an arc. If the noise is something like a microwave oven, which produces RF energy only at about 2.4GHz, then the AM radio will not help you find the problem.

I hope this helps to clarify the issues.


p.s. As an interesting experiment. If you have WiFi and a microwave oven in your house/apartment, start downloading a large file. Look at the download rate (300kB/sec. or whatever). Then, start the microwave and look at the download rate. Mine drops to about 10-20kB/sec., because the microwave interferes with the WiFi signal.

Comment: Re:Use your local ham radio club (Score 5, Interesting) 499

by bezenek (#32726396) Attached to: Tracking Down Wi-Fi Interference?

First try what is suggested by BabaChazz in his comment above and is what most Hams would do to start. Listen for the noise on an AM radio. You do not want FM, as one of the characteristics of FM is to block this noise.

Take your (preferably hand-held) radio and tune it somewhere on the dial where there is no station. Then, you can try moving it around your computer to hear all of the RF interference your motherboard, etc. are giving off. If you cannot hear this noise, something is wrong with the radio--be sure it is set to AM. :-)

Leave the radio on, and you might hear the noise start at the time your WiFi drops. If you do not, the interference is not covering the AM frequencies (an arc will cover everything), and it is probably time to call in a Ham.
It is likely you will hear it.

If you hear it, you can walk around inside and outside your house listening for where the noise gets stronger. Often this will be tracked down to a phone pole or something else.

Once you find it, contact the appropriate person (electric distribution supplier, city, etc.) Convincing someone to fix a problem like this is not always easy.


Comment: Maybe They Can Help Correct Strabismus (Score 1) 386

by bezenek (#32705996) Attached to: 3D Displays May Be Hazardous To Young Children

I know nothing about this other than my own inability to focus on different points without the aid of a stereoptic viewer. Many people can do this, but I cannot.

It would seem that anything which hinders the development of the ability to focus both eyes on a single point could be designed to help train one's eyes to do this.

Hopefully, if this has not already been researched, this issue being in the news will catch the interest of a PhD student with the proper background to look into it.


Comment: Cosmic Rays Tend to Flip Multiple Bits (Score 1) 277

by bezenek (#32685760) Attached to: Tracking Down a Single-Bit RAM Error

Cosmic ray events tend to affect multiple neighboring transistors. For this reason, they tend to affect multiple bits. However, by laying out memory cells so immediate neighbors are from different locations, the ability of single-bit-correction-double-bit-detection (SECDED) methods to detect most events is usually preserved.

The main concern is for structures with no error correction, such as the gates in the processor pipeline. Several research ideas have been put forward. See here (PDF) for a good overview of the issues.


"There is such a fine line between genius and stupidity." - David St. Hubbins, "Spinal Tap"