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Comment Why health care workers are vaccinated (Score 1) 851

The reason health care workers are required to be vaccinated is that someone contracting the flu starts to shed the flu virus for some hours before other symptoms develop. By the time someone begins to feel bad, sneeze, etc. one has already been spreading the illness for hours. (One can see how a virus that behaved in this way would be evolutionarily advantaged over a virus that spread only after the patient first noticed other symptoms.)

Since the spreading mechanism is primarily via the hands touching the nose and mouth, and then touching other surfaces (like doorknobs or keyboards) that are then touched by others, most hospitals with which I am familiar have a different policy: If an employee refuses the flu vaccine, the employee is not terminated, but is required to wear a face mask at all times when at work. This breaks the spreading pathway, albeit less efficiently.

Many hospitals even provide free, voluntary, flu vaccinations to the family members of employees, to reduce the possibility that virus particles shed by, say, a sick child will not be carried by the health care worker into the hospital (for example, in hair or on clothes). This has the added benefit of reducing time away from work to take care of, e.g., a child sick with the flu.

Comment Re:Why just 2m and 70cm? (Score 2) 50

Yes. And if one makes a 6m antenna the same physical size as a handheld 2m antenna the 6m loading coil will be larger, its series resistance will be higher, and the 6m antenna will be significantly less efficient than the 2m antenna. It will work "well enough", for suitably generous definitions of "well enough."

The optimum operating frequency for a given service can be determined (in the absence of regulatory restrictions, of course) analytically, taking atmospheric noise, antenna performance, and receiver noise figure into account. See, for example, Kai Siwiak, Radiowave Propagation and Antennas for Personal Communications." Second Edition. Boston: Artech House. 1998. Chapter 4.7.

Comment Re:Why just 2m and 70cm? (Score 4, Informative) 50

But I don't know enough about designing this kind of thing to know if that is feasible.

The SDR is feasible, in fact, easier, but the problem is the "handheld" part -- "emphasis on the word, 'handheld.'" The physical size of the antenna starts becoming uncomfortably large as the frequency goes down -- or, said another way, the efficiency of the antenna goes down with frequency if the physical size is held constant. A full-size 50 MHz quarter-wave whip antenna is 1.5 meters (or metres, if you prefer; about 59 inches) long; that's pretty unwieldy for a handheld radio.

Comment Re:31km in an Earthquake Zone (Score 2) 292

They should build this in Florida.

I'm not against this idea at all, but the water table is so high in most places in Florida that it would be really difficult to do. One needs to drill down less than 20 feet in most places to reach water. It's why one sees so few (substantially zero) houses with basements in Florida.

Comment Re:Shred of Evidence (Score 1) 402

Keep in mind that his grad students were the ones that created the controlled technology in the first place, while working in his lab, and there is no evidence (nor any accusations made by the Prosecutor at his trial) that his students ever surreptitiously transferred the controlled technology outside the US. As another commenter notes elsewhere, it's impossible to exaggerate how goofy the rules are, and Prof. Roth ignored the "obviously illogical and irrational" regulations -- to his detriment.

And if you think he "chose" to employ foreign citizens as grad students, you haven't visited a US science, technology, engineering, or math graduate school since, say, 1980 or so. The ratio of foreign citizens to US citizens among the electrical engineering doctoral students at a major US state university with which I am familiar is approximately 20:1.

Comment Re:That's what encryption is for. (Score 1) 402

It's not just trading in state secrets ("espionage"). In the US it's also the trading in controlled technologies. The difference is, a controlled technology can be transferred to any US citizen with no legal issue at all, but cannot be transferred to (certain) foreign citizens. A state secret, on the other hand, may not be transferred even to another US citizen without authorization.

Comment Re:That's only one of the problems (Score 4, Informative) 402

how does bringing them back there in anyway give China access to any "controlled technology" they don't already have?

It's the information the technologist has stored on it that is the problem. The export control laws are enforced by the Bureau of Industry and Security, and they are arcane, complex, and woefully out of date. Just to give one example, if you're a microprocessor designer, and have a design that operates at temperatures exceeding 125C, that design is controlled; carrying that design in your laptop when you go to China is a violation of the law -- whether or not it is even accessed while in China. (It's also illegal to show that design to any person of Chinese citizenship, even if you both are in the US at the time; that, too, is considered export under the law.)

Comment That's only one of the problems (Score 4, Interesting) 402

The other -- and, I would submit, more important -- reason for not taking your business laptop to China (if you're from the US) is US export control laws. The definitions of "export" and "controlled technology" have been so generalized that it is an even-money bet that the laptop of a given technologist contains information that, were he to travel to China, would result in at least a technical violation of the law -- and the penalties are severe.

Comment 828 flashing Dekatron valves (Score 3, Informative) 65

Dekatron valves are an example of a solution to the problem of making storage registers before integrated circuits made them essentially free. Making reliable working memory was one of the biggest problems faced by the early computer hardware designers, and Dekatron valves (tubes) were one of the more creative solutions. Of course, the reliability of solid-state electronics made them a technological backwater, but that makes them no less interesting -- it's fun to speculate on how things would have worked out if cold-cathode valves remained the dominant storage technology.

Comment Find a value the old guard values (Score 3, Interesting) 379

In my experience (speaking as someone old enough to remember watching the coverage of President Kennedy's assassination on television), the odds are not good, since the existing people are typically happy with the existing system -- otherwise, they would have changed it by now. However, one hope is to find a value of your organization -- and it'll be specific to each organization -- that would be improved by the change you desire.

Note that this is not your value, but a stated value of the "old guard" that could be improved by the new system -- and, usually, avoiding the mortality of the old guard itself is not an acceptable value. Extra credit if you can arrange a discussion of the old guard value in such a way that Bob can take credit for the improved performance of the new system.

Often, like so much in life, people with existing beliefs have to pass on before new ideas are accepted; ask yourself if you will be open to replacing your Google Docs system by something you don't know and have never heard of, in ten or twenty years' time.

Recognize that you will have to do all the work to install the new system, just as Bob did to install his own system years ago.

Comment Re:Just how would this work? (Score 1) 257

Can you give any examples where this change would stop or slow scientific progress?

Absolutely. Ever heard of co-processors, or hardware accelerators? They are hardware implementations of algorithms that are used to speed computation and reduce power consumption, and are in every modern microprocessor.

Since they are hardware implementations of software algorithms, if this change were in force the manufacturer and seller of hardware accelerators (and the computer that contains them) would be vulnerable to patent infringement lawsuits from holders of software patents. However, if the processor did not contain them, this would not be the case, so there would be great incentive for manufacturers to design microprocessors, and computers in general, without them.

Having to design computing hardware without embedded data processing algorithms would slow progress a lot -- I wouldn't want to do it. Especially with attorneys trying to tell me that my address decoder or bus contention manager or AES-128 encryption engine is a hardware implementation of their software algorithm. Eek.

Passing the buck to the hardware portion of the computer, instead of the software, doesn't solve the problem.

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