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Comment IBM and more (Score 4, Interesting) 615

Eric's history is interesting and valuable as long as you realize it is based on his stove-piped career. There are glaring omissions. In particular there was this company called IBM that dominated the data processing industry for most of the 20th century. The end of the 36-bit era and the universal use of addressable 8-bit bytes began when IBM introduced the System/360 in 1964, not when DEC finally stopped making PDP-10s in 1983. ASCII did not grow out of anything, it was a fresh creation of a new standard. IBM even pretended to support it, though it used its own 8-bit code, EBCDIC. The short Unix commands were optimized for Teletype machines. Video displays were not cheaper than Teletypes at first, they succeeded because they were much faster and far more user friendly, not because they saved money on consumables. Many early minicomputers supported the native "current loop" interface to the Model 33 Teletype. Tektronix storage tubes deserve a mention. They made graphical computing possible when memory was far too expensive for display buffers. RS232 is still alive and well in the Arduino world; level shifting there means 5 volt to 3 volt. I would mention the 16-bit programming address space that almost all minicomputers had, which forced programs to fit in 64K byte segments. It made it hard to grow software because it forced you to constantly restructure to fit in small overlays. I once had an argument with Gordon Bell of DEC about this when the PDP-11 was introduced; he thought any program larger than 64K *should* be broken up. In general hardware people had a greater influence on computer design in the early years. Early microcomputers adopted the same 16-bit addressing scheme. The Motorola 68000, introduced in 1979, was the first to allow a larger address space (24-bit at first, but architecturally 32-bit). Line printers and multi-part fan-fold paper forms also deserve mention. IBM printers used to be controlled by a loop of paper tape with holes that allowed a fast move to the top of a new page or even a point in the middle, hence form-feed and vertical tab. USB's popularization by Apple deserves mention too, especially since the are now leading the push for USB-C.

Comment Re:Sounds good (Score 2) 57

The data you link to shows that large scale hydro energy output has declined sharply since 2010, presumably due to the drought, while wind and solar output have increased by about the same amount, making up the difference and leaving thermal output flat over the period, since overall demand was flat. If the drought is temporary, this will correct itself; if the drought is due to long term climate change, continued growth in wind and solar will soon start to reduce thermal generation needs. Either way, it's wind and solar that are working, large scale hydro not so much.

Comment Re: I wouldn't have (Score 2) 125

I attended a persentation about ARPANET by BB&N back in 1971 and I asked about encryption. I was told that if encryption was included, the project would have to be classified, which they didn't want. Instead they expected each link would be encrypted for military use, employing NSA black boxes. On the other hand, Ethernet, developed at Xerox PARC a couple of years later, used 48-bit addressing. If ARPANET had done that, the added two bytes would have been insignificant even then, and we'd have 32,768 times as many addresses in IPv4, and we'd be just fine even with IoT.

Comment Re:Am I reading this right? (Score 4, Informative) 79

That's not quite how it works. In zero g, just adding Helium pressure to a tank won't accomplish much. You either have to use some kind of pressurized bladder to force the liquid down (ok for thrusters, too big a weight penalty for the main engine fuel and oxidizer) or supply a small acceleration, say from auxiliary thrusters, to settle the liquid to the bottom of the tank prior to ignition. Then He pressure can push the liquid into the main pumps which, in turn, provide enough pressure to force the liquid into the engine against its internal pressure.

Comment Re:My own prediction (Score 4, Insightful) 254

... Government subsidizing the development of new technologies has the universal effect of distorting competition and making any such projects fail. ...

Like the railroads, airplanes, nuclear power, computers, the Internet, GPS, biotech, all of which had heavy US government subsidy in the beginning.

Comment How many Congressional leaders.. (Score 1) 289

or other high level government officials, including past Secretaries of State, have ever had years of their email scrutinized by the FBI for possibly classified information? And anyone who watches Fox News knows that there has been a steady stream of leaks from the FBI on their investigation of Mrs. Clinton. Has anyone in the FBI been disciplined for the leaks? And was the NSA aware of Clinton's private e-mail server? Did they complain to her or her boss about it? If not why not?

Comment Re: Why should chirality is be considered strange? (Score 1) 56

The right hand rules in electromagnetism isn't a fundamental property of the universe, but just a result of sign convention. If we had a signed positive charge to electrons and flipped the definition of current, you would end up with a left hand rule. If we had picked the opposite definition of what the positive direction of the magnetic field means , we would have left hand rules. You can make the vector cross product left handed instead of right handed, and physics is fundamentally the same with some sign flips in definitions that are arbitrary human notation.

Correct. But non-conservation of parity in the weak interaction does produce chirality. However it is not clear how this property of sub-atomic particles could bias chemical reactions to favor one handedness over the other. More likely chirality in biology reflects a "first mover advantage" in early evolution. Descendants of a self-replicating molecule that happened to form in one chirality may simply have come to dominate life. Another explanation is that life did not evolve on Earth and was seeded by a single chiral bacteria.

Comment Another vector for malware (Score 1) 382

In past exploits, attackers have scattered a few shiny USB thumb drives in parking lots in the hope that some employee will plug one into a work computer, infecting it with the malware payload the drive contains. Soon USB-C headphones will be the vector of choice. Who is going to do a security audit on a headphone?

Comment Re: You suck at nitpicking (Score 1) 367

I worked a NASA MSC in 1966 and 67 and computers were available to all engineers and widely used for calculations. We even had a virtual reality simulator using an early polygon processor developed by GE that filled several relay racks in Building 16. Computers were used to manage the Apollo project as well, using PERT.

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