U.S. digital cable is not ATSC (8-VSB modulation) over-the-air broadcast signal compatible. Instead, the main MPEG2 payload is carried in 64-QAM or 256-QAM modulation, within RF channels that fit the usual US-standard 6 MHz spacing. Alongside this, are one or more "out-of-band" carriers that use a different modulation format and lower data rate, that carry channel maps and other administrative information. Finally, there is an upstream (settop box to head-end) channel in RF bands lower in frequency than the downstream RF, that is used for administrative purposes and for pay-per-view.
The signal structures are described in published standards freely available from SCTE. The out-of-band and reverse channels have two different standards, reflecting the original developments by General Instrument (now Motorola) of one standard, and by Scientific Atlanta (now Cisco) of the other.
Much (but not all) of the content is covered by "conditional access" (encryption), the details of which are of course unpublished.
The good news about Paris sidewalks is that while carefully scanning them for merde de chien (dog poo), I found an F200 (around US$30 at the time) banknote. The bad news is that this is almost enough to buy lunch. The good news is that lunch runs from noon to 2PM.
You want a sidewalk challenge, try Saigon. The sidewalks are choked with parked motorbikes. Those sidewalks that are not choked with parked motorbikes, are at times challenged by moving motorbikes attempting to gain advantage over streets that are choked with slowly moving motorbikes.
This technology is known but is lacking in cool-factor. One of its central mechanisms functions only at dismal efficiency, has an annoying tendency to run backwards, and requires a massive capital investment to make enough product to meet system demand.
"Easy" configuration for third-world (tropical) environs in fact required fundamental re-engineering. (Or: use only in temperate environs allowed development of a considerably simplified version.)
This only works if you have a closely spaced network of seismometers, and the computing power to rapidly assess whether a large quake is beginning. There aren't any real precursors to many large quakes. You can detect a strong P-wave with seismometers placed at close intervals along known faults, and use that to electronically transmit an alert signal.
Your only advantage here is that electronic communication can outrun earthquake waves, that propagate at 5000 m/s or less. The more destructive S-waves and surface waves also propagate more slowly than the initial P-wave, yielding a little extra advantage as distance increases from the epicenter.
None of this is worth much if the quake hits near where a train happens to be operating.
An amusing demonstration for me came after the Loma Prieta quake. I (fortunately) was out of town for the main event, but returned during a time when aftershocks were still fairly frequent.
I was listening to a call-in radio program one evening where the quake was the topic. An aftershock occurred, and a caller on the line from near the original epicenter said "oh no, there's another one!"
I did a quick mental calculation for around 160km, waited that number of seconds, and felt a small jolt and shaking at my location.
By contrast, a few evenings ago there was an M2.9 centered only a few km away from me. There was zero warning, only a sharp shove of a cm or two and a booming sound. Because that same fault system is the most likely serious threat here, my most likely warning for the M6.5+ that studies suggest as its typical large quake, will be zero.
Fogging of film by peeling the adhesive tape has been well-known for years. I usually cut the end off with scissors rather than peeling.
Similarly, one should be cautious about rewinding film too quickly in the camera, and in unrolling and reeling film in the darkroom, especially in dry conditions.
If one can even find film, of course.
My favorite is using a Breathe Right strip with dark-acclimated vision. Peeling the wrapper open emits light, as does peeling the backing paper off the strip.
How long before TSA begins confiscating adhesive tapes in carry-on baggage?
As one who also worked for Motorola during Ms. Warrior's warming of the CTO seat, I third this.
It was never clear what, apart from the silly phrase "Seamless Mobility", she actually contributed.
While it would not be correct to pin the massive failings of this formerly great company solely upon her, it must be considered that she was elevated to the CTO position by a management regime whose combined avarice and comprehensive ineptitude are now undeniable.
Her qualifications are not stellar, and her actual record of performance at anything apart from being hired into high profile positions, is regrettably deficient.
... retrogress. The first computer that I programmed was the IBM 1620, designed around 1959. Its core memory was in an oil bath, but this was for heating (presumably to a temperature where it had the desired magnetic behavior) rather than cooling. When you powered this machine on, it required 10-20 minutes to warm the memory up, before it would allow you to compute.
Go look at the corporate Web sites for Thomson or Pearson (two of the worst offenders, in high prices and in ridiculous weight of the books and in edition-churning) and read the histories. These conglomerates have consolidated a former diversity of publishers, leading to a much less competitive market.
It is the duty of the student-consumer to fight back by using arbitrage: international student editions.
One example: Introduction to Electrodynamics by Griffiths. Amazon shows $107.20, list $134.00. You can order it from India for maybe $45.00 including shipping. It arrives quickly. Then you look at the rupee price sticker that someone left on the book, and find that it sold in India for the equivalent of US$4.50.
You get the book for less than half price, and some enterprising fellow in India gets a 7x markup (I'm subtracting the cost of shipping).
Chances are that the international student edition will also be more convenient to use, in that it will be printed on ordinary paper rather than the cripplingly heavy clay coat paper that nearly all American editions of textbooks are printed on.
I weighed a recent edition of a popular introductory biology textbook (Campbell)... over 7 pounds. One cannot study from such a book, much less lug it around on campus.
At these outrageous prices, one might expect that the publisher would be doing something apart from ringing the cash register and permuting pages to create new "editions" to force obsolescence.
Wrong. The editors are too busy making new editions to pay attention to essentials. Textbooks, especially the back-of-book solutions, are rife with errors. Errata, if they are issued at all, are often far from complete.
The editors, despite their great energy at creating new editions, appear to have little or no expertise either in the subject matter or in pedagogical technique.
Fowles and Cassiday's Analytical Mechanics lists for a whopping $204.95 ($163.96 from Amazon).
This book spends pages on marginally relevant historical discussion, then in the essential material, explains so little and skips so many steps in derivations, that one is left hanging off the edge of a cliff for topic after topic. Don't get me wrong: historical discussion is wonderful, but not when it uses page space that should have been used for more complete exposition. Especially when the page space is priced like Manhattan real estate.
I have found that it is useful to buy cheap old used copies of classic textbooks, from a time before color illustrations, dense clay coat paper, and edition-churning. Many of these books are clearly superior to modern editions.
Good grief. I am a (returning adult) physics student at a second-tier state university. The electronics course that was required for the physics major, required a considerable amount of laboratory work.
How could one of the most elite engineering schools in the nation not have extensive laboratory work for an EE?
This sounds like American Basic Science Club, San Antonio, Texas.
I convinced my folks to subscribe to the first 4 kits (electronics series). I probably still have a couple of the components.
Yes there were dangers as there always were with B+ supplies for vacuum tubes, and AC mains power, but learning to deal with those was part of the learning experience.
Here is one of their brochures:
http://www.samstoybox.com/toypics/ABSC/ABSC1.html
After 30+ years of writing code for a living, I decided to go back to university for a physics degree. My school (undergrad. state institution) has around 7000 students, and perhaps 35 of these are physics majors.
My school requires a course in computer methods as a part of the physics major, and I have been afforded a very recent opportunity to observe traditional-aged fellow students while taking this course.
Such a course is essential. While students at our school are introduced to Mathematica as part of the calculus sequence, this exposure is cursory and is only interactive; it does not require actual programming.
My computer methods course was a first presentation for its lecturer, and arguably was a bit too ambitious in breadth. We had programming assignments in Mathematica (both procedural and rule-based), and interactive and programmed use of GNU Octave (Matlab clone). We also were required to write a program in C/C++.
Throughout the class there was an emphasis upon learning and writing documents in LaTeX, including a considerable amount of equation-writing. We also used the old Bell Labs Graphviz "dot" program, both as an arcane and slightly bizarre introduction to programming per se, and to generate graph figures for inclusion into the reports written in LaTeX.
Adding to the confusion from breadth is the fact that one professor, for his optics class, prefers and supplies his examples in Mathcad.
I believe that it's fair to say that most students found this class to be a nearly excruciating experience, which is an indication that it had worthwhile and challenging content. The breadth and pace of presentation needed to be reduced a bit.
Out of the 10 or so students in the class, only I had any previous programming experience. I found the work load challenging, more in the underlying problems than in the technical aspects of writing code. By contrast, at most one of the other students had previously used any text editor apart from Word, or were aware of TeX/LaTeX.
The course had some challenging conceptual content (e.g. generating attractor maps by iterative solution of cubic equations with starting points gridded across a region of the complex plane) as well as fairly extensive technical content.
I will admit a pathological allergy to Excel, with the exception that it is somewhat handy for graphing and doing simple regression fits. I am glad that this course did not spend time on Excel.
Again, this course needed to be recalibrated downwards a bit in breadth of topics. Numerical stability and precision effects were only briefly mentioned, but did benefit by a good example or two.
There is no way that a semester course could approach both the extensive technical topics, and actual numerical analysis. That needs to be a separate course.
Also missing from this course was any coverage of experiment automation (which usually means LabView). This is another important topic, but there simply is not time in a semester to cover it alongside everything else.
At least two of the students gained some enthusiasm for LaTeX as a result of this class, and have used it to write assignments for other classes.
My reading of the article tends to point away from the autothrottle itself, unless its connection to the engine controls is independent of the thrust levers, and under some condition carries greater authority.
The engine display has Commanded and Actual EPR indicators. Flight crew noticed a disparity between these, and attempted to correct by increasing the thrust lever settings manually. The engines continued to fail to develop the needed power.
This points toward fuel quality, fuel supply, something in common to both engines and their engine controls, or the connection(s) (and the connection might have some un-obvious aspects) between autothrottles, thrust levers, and the engine controls.
All of this assumes, of course, that the pilots' statements and the reporting match the facts.
One question is whether the engines could have developed the needed additional power in time - how late was the thrust deficit noticed, compared the normal expected lag in engine response? The report gives the impression that the pilots believed they commanded something that was feasible, and it did not happen.
Note also that the report claims that L and R autothrottles are independent systems, and that both engines failed. That means either that the autothrottles are not at fault, or that something in common between L and R systems (which obviously can include the design and implementation) failed, or that something downstream of the autothrottles failed identically on both sides.
I don't know that it's quite accurate to say that older movies do not benefit from HD.
What seems more accurate is that we have so much experience in seeing movies on SD TV (and worse, VHS) and for those of us who are older, with considerably worse SD TV performance, that our expectations are nearly met by VHS, fully met by conventional broadcast, and exceeded by a decently encoded DVD played through the definitely superior (to composite) S-Video connection.
If you have never seen (or the experience has faded from memory) a good Technicolor print, or a Cinerama showing of 2001: A Space Odyssey, it is difficult to realize how beautiful real film can be, even as far back as a 1939 production (The Wizard of Oz, part black and white, part Technicolor).
A lot depends upon the nature of the film. If most of the experience is in the dialog, with My Dinner With Andre being the extreme case, or Glengarry Glen Ross, visual quality is not really all that important. If it is an immersive sensory overload, like 2001, or the first Star Wars, even HD will not do it justice.
I recently, and never having seen it on film, saw Killer of Sheep on conventional DVD projected in an auditorium. I was in awe of the quality of the (low budget black and white, but in many of its scenes beautifully filmed) experience.
Something like Saving Private Ryan could be seen one way on film, another way in HD, and yet another in SD, and be different yet still effective in each of the three. Gothika I have only seen in HD (HBO); it was very effective there, but I cannot see that it would be any better on film, or very effective at all in SD with ordinary sound. Rabbit-Proof Fence was a gut-slammer on film, but not especially effective in the admittedly awful environment of airline seatback TV (perhaps an unfair comparison, because I saw it first on film). It would almost certainly benefit by HD presentation, because it relies upon both story and immersive visuals.
The article failed to mention that conventional integral tripack color films, especially print films of the 1960s-70s, degrade with dismaying speed.
Technicolor dye transfer (imbibition) prints were much less fugitive. Color separations onto black and white film stock (often termed YCM for yellow, cyan, magenta) are much more robust. Production of these separations (and imbitition relief "matrix" films) was intrinsic to the Technicolor printing process (even if the film was shot in conventional tripack negative, then transferred to Technicolor for printing), and films where these intermediates were saved (or where someone presciently thought to have a set of YCMs made), are much safer for the future than anything kept only on color stock.
In the 70s there were some photo places (especially in Los Angeles) that marketed Eastman Color Negative 5247 movie film (short-end remnants from the movie industry) as a cheaper alternative for 35mm color negative still photography, and printed this onto 5283 color print film (same as movie prints) for 35mm slides.
I recently found a few boxes of these that I had shot back then (and stored under entirely careless, or Arrhenius/Murphy if you prefer, conditions). I am not good at evaluating color negatives by eye, but the positives were faded either to mutated colors or to almost nothing.
Even simple technologies can have amazingly short shelf lives under conditions of disuse. I recently turned on my stereo system after close to 3 years of not being used. The amplifier, CD player, and LP turntable all failed to operate. Part of this might have been due to de-formed electrolytic capacitors; these appear to have more-or-less repaired themselves after a couple of hours with the power turned on. Both the CD player and the turntable suffered additional electromechanical problems that required a combination of manual exercise and cleaning to rectify.
None of these devices have anywhere near the scary sophistication of a modern hard disk drive.
Seeing as I cannot remember what I last set my external firewall password to, imagine the additional challenge of future Hollywood being bitten deeply in the butt by present Hollywood's favored time-bombed destined-to-be-lost-art proprietary DRM technologies, with the keys long since dissipated in Hollywood's perennial miasma of mergers, acquisitions, lawsuits, cocaine, and personal vendettas.
Agreed. When I was quite young, I was taken on a visit to the Texas state comptroller's office, and was allowed to push a button on a running 650, and to look at the marvelously space age looking RAMAC disk.
I later was taken on a tour of a SAGE (air defense radar processing) installation with its massive AN/FSQ7 vacuum tube computer and CRT displays with their vastly Buck Rogers light pens.
I might still have a relic of the IBM vacuum tube era: a plug-in tube circuit module. This was a U-shaped metal frame containing a single socketed vacuum tube, some phenolic wafers that supported various resistors and capacitors, and a plug on the bottom.
Mine, if it still exists in a box in the garage, is no longer in original condition. I removed the original components, and built upon it a 12AX7-based audio modulator (Popular Electronics magazine project) for a HeNe laser (also a PE project). The modulator actually worked for a few minutes before a power supply capacitor shorted and smoked itself and the plate transformer.
My first paid job was operating and programming an IBM 1401. Its model 1311 "washing machine" removable pack disk drives stored 2,000,000 characters, or 2,980,000 in "track record" mode (if your program could afford the memory to read and write full tracks instead of 100 character sectors). The seek actuator was hydraulic, and there was usually a small pool of leaked oil at its base.
I have worked at a couple of sites in Germany that used the 3-6 person cluster offices. It's not a bad plan, as long as the people in the office have similar needs and tolerance for conversation level and physical order. It worked well enough for me, because the people around me were fairly quiet.
By contrast, in the U.S. there seems to be a lot of casual conversation and a tendency to escalate the volume as more people become enmeshed in the conversation.
I have shared 2 person closed offices with 1) a person who mumbled to himself in German, then 2) a person who constantly ate sunflower seeds and made weird moaning and smacking noises while doing it, along with shell cracking noises. Both drove me to distraction.
A very brief experience in a (very low wall) cube environment in India gave an interesting contrast. The work style appeared to be highly social, with 2 or more people very frequently clustered around one computer. People appeared to be disciplined or at least considerate, and kept the conversation volume level low.
I need total silence to retain enough concentration to work on difficult problems and to produce coherent written results. Conversation is an occasional part of the process, but for me it is much more the exception than the rule.
Also, I do not see how anyone can expect significant technical work to occur without whiteboards, and ones whose contents will remain undisturbed for days. I do not use these much myself, but there are times when they are essential, and some people use them constantly.
Notebooks are ergonomic catastrophes, and are a great way to lose work through breakage and theft.
There was a much more descriptive term in the '70s for the so-called open office. It was called a "bull pen". When I have an actual nightmare about working environments, around 70% of the time it takes place in a downwards extension of the classic gray linoleum-topped desk-matrix bull pen: a large room full of rows of those cheap long folding tables, with closely spaced computers atop them, and no permanent seat assignments.
People who make the decisions for these crappy environments typically operate in a sub-world saturated with conversation and bargaining. A "sustained effort" means exercising self-similar weekly, monthly, and quarterly rituals with minor variations.
This is a fundamentally different world than that of novel and deeply analytic problem solving in mathematics and code, requiring weeks, months, or longer.
This is not exactly the work referenced in the original article, but it is very likely related to it. Anything that requires a cell of isotopically weird (carbon 13) acetylene sounds fun to me.
The crucial element appears to be a highly stabilized laser that is used in the receiver as a local oscillator to recover (by optical heterodyne detection) a UHF RF carrier that carries the actual QAM.
I had read speculative/theoretical statements about optical heterodyne detection years ago (probably around '94). It might've taken this long to get a stable (and monochromatic) enough local oscillator to demonstrate it in a potentially useful state.
Neither this article, nor anything linked from it and accessible without subscription, describes the result in any useful detail.
What is routinely done today in hybrid fiber/coaxial cable (HFC) cable TV systems, is to use linear RF-band, often 50-750MHz in 6MHz (North American standard) bands corresponding to television channels. Both 64- (6 bits/baud) and 256- (8 bits/baud) QAM modulation standards are used. 64-QAM has been around since maybe 1996.
256-QAM requires a better signal/noise ratio through the transmission path, and better A/D resolution and more demodulation work in the receiver. 256-QAM gives around 38.8Mb/s payload rate after subtracting TV standard (ITU J.83B) ECC and packet overheads. 256-QAM is seeing increasing use as better chip technology makes the demodulators cheap, as cable plant is upgraded to push fiber farther out toward the end subscribers with better signal quality.
700MHz / 6MHz = 116 TV channels * 38.8Mb/s = roughly 4.5Gb/s digital capacity for QAM on a 700MHz RF bandwidth. Again, this is done routinely today, except of course a TV receiver only selects and demodulates a single 6MHz channel at a time.
One could WDM a number of 700MHz RF ensembles onto a fiber, but this of course requires source lasers (ones designed for wideband linear modulation, or with $$$ external modulators) with precisely tuned and stabilized wavelengths, and corresponding optical splitter/filters, individual optical receivers for each wavelength, and RF-band demodulators for however many channels the RF band has been divided into.
Terabit through this conceptually straightforward WDM approach would require over 200 such optical carriers (a couple of racks of very expensive equipment. It's feasible, but not something you will have on the side of your house (even receive-only) in the near future.
I invited an OEM sales rep. for a disk manufacturer to give a presentation a few years ago. He told of their lights-out automated factory. It would have been cool to see pictures, but it is difficult to take pictures of a lights-out factory.
Examining the price/capacity trendline on his slides, I projected that by perhaps 2009, they would be paying customers to take the drives.
This leads to one of three possible conclusions:
1) Disk drives contain something foul that someone is willing to pay to be rid of
or
2) The Bush administration subsidizes the disk drive industry (and its greatest consumption motivators: the porn and ripped music distribution industries) to make certain that new drives, all of which contain Super Secret Surveillance technology, are widely deployed
Kodak's Spin Physics division introduced, I believe in 1986, the Ektapro 1000 high speed scientific imaging system, with an NMOS sensor.
"Staring focal plane array" (FPA) systems (typically infrared) for military use probably pre-date this and are comparable to digital cameras. Scanning FPA systems are earlier and might also qualify, depending upon where you care to draw the line.
One effect of recent trends in interpretation of the federal Fair Labor Standards Act, has been to make the situation even more difficult for people who do programming or engineering work without having a college degree.
In the lawyerly search for black-and-white distinguishing criteria for who is doing creative or managerial work vs. who is a mere crank-turning technician, government apparently looks to its own qualification criteria: immigration preference, and "qualified personnel" clauses from government contracting (a field where one finds that great exception, unionized engineers).
It could be argued that this has an effect of age discrimination, in that years ago it was much more common than now to be able to enter the computing field without having a CS degree, or any degree at all. It could be further argued that companies are quite willing to go along with this, because it provides a path to displace older and higher-priced IT workers (by reclassifying them to lower-paid status), while maintaining some defense against age discrimination claims.
At my former employer (Fortune 500 technology company), I was at the second-highest step on the technical career ladder (yes, we all know that ladder is built of smoke, supported by mirrors). After whatever lawyering fad resulted in the new spin on FLSA, the company issued HR policy that said in effect that I could not have been hired for any engineering position. Their interpretation of the computer-related-fields exemption included only management information systems and networks, and not product design and development engineering.
As might be expected, this company is a leader in H1B visa use, and in moving work offshore.
Slashdot Mirror
U.S. digital cable is not ATSC (8-VSB modulation) over-the-air broadcast signal compatible. Instead, the main MPEG2 payload is carried in 64-QAM or 256-QAM modulation, within RF channels that fit the usual US-standard 6 MHz spacing. Alongside this, are one or more "out-of-band" carriers that use a different modulation format and lower data rate, that carry channel maps and other administrative information. Finally, there is an upstream (settop box to head-end) channel in RF bands lower in frequency than the downstream RF, that is used for administrative purposes and for pay-per-view.
The signal structures are described in published standards freely available from SCTE. The out-of-band and reverse channels have two different standards, reflecting the original developments by General Instrument (now Motorola) of one standard, and by Scientific Atlanta (now Cisco) of the other.
Much (but not all) of the content is covered by "conditional access" (encryption), the details of which are of course unpublished.
You want a sidewalk challenge, try Saigon. The sidewalks are choked with parked motorbikes. Those sidewalks that are not choked with parked motorbikes, are at times challenged by moving motorbikes attempting to gain advantage over streets that are choked with slowly moving motorbikes.
This technology is known but is lacking in cool-factor. One of its central mechanisms functions only at dismal efficiency, has an annoying tendency to run backwards, and requires a massive capital investment to make enough product to meet system demand. "Easy" configuration for third-world (tropical) environs in fact required fundamental re-engineering. (Or: use only in temperate environs allowed development of a considerably simplified version.)
This only works if you have a closely spaced network of seismometers, and the computing power to rapidly assess whether a large quake is beginning. There aren't any real precursors to many large quakes. You can detect a strong P-wave with seismometers placed at close intervals along known faults, and use that to electronically transmit an alert signal.
Your only advantage here is that electronic communication can outrun earthquake waves, that propagate at 5000 m/s or less. The more destructive S-waves and surface waves also propagate more slowly than the initial P-wave, yielding a little extra advantage as distance increases from the epicenter.
None of this is worth much if the quake hits near where a train happens to be operating.
An amusing demonstration for me came after the Loma Prieta quake. I (fortunately) was out of town for the main event, but returned during a time when aftershocks were still fairly frequent.
I was listening to a call-in radio program one evening where the quake was the topic. An aftershock occurred, and a caller on the line from near the original epicenter said "oh no, there's another one!"
I did a quick mental calculation for around 160km, waited that number of seconds, and felt a small jolt and shaking at my location.
By contrast, a few evenings ago there was an M2.9 centered only a few km away from me. There was zero warning, only a sharp shove of a cm or two and a booming sound. Because that same fault system is the most likely serious threat here, my most likely warning for the M6.5+ that studies suggest as its typical large quake, will be zero.
Similarly, one should be cautious about rewinding film too quickly in the camera, and in unrolling and reeling film in the darkroom, especially in dry conditions.
If one can even find film, of course.
My favorite is using a Breathe Right strip with dark-acclimated vision. Peeling the wrapper open emits light, as does peeling the backing paper off the strip.
How long before TSA begins confiscating adhesive tapes in carry-on baggage?
It was never clear what, apart from the silly phrase "Seamless Mobility", she actually contributed.
While it would not be correct to pin the massive failings of this formerly great company solely upon her, it must be considered that she was elevated to the CTO position by a management regime whose combined avarice and comprehensive ineptitude are now undeniable.
Her qualifications are not stellar, and her actual record of performance at anything apart from being hired into high profile positions, is regrettably deficient.
Graphene exhibits a Quantum Hall Effect at room temperature, provided one happens to have a 29T magnet available.
We would not want anyone with deep knowledge of prior art to interfere with the crucial mission of supporting claims on the obvious or venerable.
It is the duty of the student-consumer to fight back by using arbitrage: international student editions.
One example: Introduction to Electrodynamics by Griffiths. Amazon shows $107.20, list $134.00. You can order it from India for maybe $45.00 including shipping. It arrives quickly. Then you look at the rupee price sticker that someone left on the book, and find that it sold in India for the equivalent of US$4.50.
You get the book for less than half price, and some enterprising fellow in India gets a 7x markup (I'm subtracting the cost of shipping).
Chances are that the international student edition will also be more convenient to use, in that it will be printed on ordinary paper rather than the cripplingly heavy clay coat paper that nearly all American editions of textbooks are printed on.
I weighed a recent edition of a popular introductory biology textbook (Campbell) ... over 7 pounds. One cannot study from such a book, much less lug it around on campus.
At these outrageous prices, one might expect that the publisher would be doing something apart from ringing the cash register and permuting pages to create new "editions" to force obsolescence.
Wrong. The editors are too busy making new editions to pay attention to essentials. Textbooks, especially the back-of-book solutions, are rife with errors. Errata, if they are issued at all, are often far from complete.
The editors, despite their great energy at creating new editions, appear to have little or no expertise either in the subject matter or in pedagogical technique.
Fowles and Cassiday's Analytical Mechanics lists for a whopping $204.95 ($163.96 from Amazon). This book spends pages on marginally relevant historical discussion, then in the essential material, explains so little and skips so many steps in derivations, that one is left hanging off the edge of a cliff for topic after topic. Don't get me wrong: historical discussion is wonderful, but not when it uses page space that should have been used for more complete exposition. Especially when the page space is priced like Manhattan real estate.
I have found that it is useful to buy cheap old used copies of classic textbooks, from a time before color illustrations, dense clay coat paper, and edition-churning. Many of these books are clearly superior to modern editions.
The publishers are evil and need to die.
How could one of the most elite engineering schools in the nation not have extensive laboratory work for an EE?
This sounds like American Basic Science Club, San Antonio, Texas. I convinced my folks to subscribe to the first 4 kits (electronics series). I probably still have a couple of the components. Yes there were dangers as there always were with B+ supplies for vacuum tubes, and AC mains power, but learning to deal with those was part of the learning experience. Here is one of their brochures: http://www.samstoybox.com/toypics/ABSC/ABSC1.html
My school requires a course in computer methods as a part of the physics major, and I have been afforded a very recent opportunity to observe traditional-aged fellow students while taking this course.
Such a course is essential. While students at our school are introduced to Mathematica as part of the calculus sequence, this exposure is cursory and is only interactive; it does not require actual programming.
My computer methods course was a first presentation for its lecturer, and arguably was a bit too ambitious in breadth. We had programming assignments in Mathematica (both procedural and rule-based), and interactive and programmed use of GNU Octave (Matlab clone). We also were required to write a program in C/C++.
Throughout the class there was an emphasis upon learning and writing documents in LaTeX, including a considerable amount of equation-writing. We also used the old Bell Labs Graphviz "dot" program, both as an arcane and slightly bizarre introduction to programming per se, and to generate graph figures for inclusion into the reports written in LaTeX.
Adding to the confusion from breadth is the fact that one professor, for his optics class, prefers and supplies his examples in Mathcad.
I believe that it's fair to say that most students found this class to be a nearly excruciating experience, which is an indication that it had worthwhile and challenging content. The breadth and pace of presentation needed to be reduced a bit.
Out of the 10 or so students in the class, only I had any previous programming experience. I found the work load challenging, more in the underlying problems than in the technical aspects of writing code. By contrast, at most one of the other students had previously used any text editor apart from Word, or were aware of TeX/LaTeX.
The course had some challenging conceptual content (e.g. generating attractor maps by iterative solution of cubic equations with starting points gridded across a region of the complex plane) as well as fairly extensive technical content.
I will admit a pathological allergy to Excel, with the exception that it is somewhat handy for graphing and doing simple regression fits. I am glad that this course did not spend time on Excel.
Again, this course needed to be recalibrated downwards a bit in breadth of topics. Numerical stability and precision effects were only briefly mentioned, but did benefit by a good example or two.
There is no way that a semester course could approach both the extensive technical topics, and actual numerical analysis. That needs to be a separate course.
Also missing from this course was any coverage of experiment automation (which usually means LabView). This is another important topic, but there simply is not time in a semester to cover it alongside everything else.
At least two of the students gained some enthusiasm for LaTeX as a result of this class, and have used it to write assignments for other classes.
The engine display has Commanded and Actual EPR indicators. Flight crew noticed a disparity between these, and attempted to correct by increasing the thrust lever settings manually. The engines continued to fail to develop the needed power.
This points toward fuel quality, fuel supply, something in common to both engines and their engine controls, or the connection(s) (and the connection might have some un-obvious aspects) between autothrottles, thrust levers, and the engine controls.
All of this assumes, of course, that the pilots' statements and the reporting match the facts.
One question is whether the engines could have developed the needed additional power in time - how late was the thrust deficit noticed, compared the normal expected lag in engine response? The report gives the impression that the pilots believed they commanded something that was feasible, and it did not happen.
Note also that the report claims that L and R autothrottles are independent systems, and that both engines failed. That means either that the autothrottles are not at fault, or that something in common between L and R systems (which obviously can include the design and implementation) failed, or that something downstream of the autothrottles failed identically on both sides.
Allegations of Linguistic Similarity Unearthed, Dismissed as Ungrounded
What seems more accurate is that we have so much experience in seeing movies on SD TV (and worse, VHS) and for those of us who are older, with considerably worse SD TV performance, that our expectations are nearly met by VHS, fully met by conventional broadcast, and exceeded by a decently encoded DVD played through the definitely superior (to composite) S-Video connection.
If you have never seen (or the experience has faded from memory) a good Technicolor print, or a Cinerama showing of 2001: A Space Odyssey, it is difficult to realize how beautiful real film can be, even as far back as a 1939 production (The Wizard of Oz, part black and white, part Technicolor).
A lot depends upon the nature of the film. If most of the experience is in the dialog, with My Dinner With Andre being the extreme case, or Glengarry Glen Ross, visual quality is not really all that important. If it is an immersive sensory overload, like 2001, or the first Star Wars, even HD will not do it justice.
I recently, and never having seen it on film, saw Killer of Sheep on conventional DVD projected in an auditorium. I was in awe of the quality of the (low budget black and white, but in many of its scenes beautifully filmed) experience.
Something like Saving Private Ryan could be seen one way on film, another way in HD, and yet another in SD, and be different yet still effective in each of the three. Gothika I have only seen in HD (HBO); it was very effective there, but I cannot see that it would be any better on film, or very effective at all in SD with ordinary sound. Rabbit-Proof Fence was a gut-slammer on film, but not especially effective in the admittedly awful environment of airline seatback TV (perhaps an unfair comparison, because I saw it first on film). It would almost certainly benefit by HD presentation, because it relies upon both story and immersive visuals.
Technicolor dye transfer (imbibition) prints were much less fugitive. Color separations onto black and white film stock (often termed YCM for yellow, cyan, magenta) are much more robust. Production of these separations (and imbitition relief "matrix" films) was intrinsic to the Technicolor printing process (even if the film was shot in conventional tripack negative, then transferred to Technicolor for printing), and films where these intermediates were saved (or where someone presciently thought to have a set of YCMs made), are much safer for the future than anything kept only on color stock.
In the 70s there were some photo places (especially in Los Angeles) that marketed Eastman Color Negative 5247 movie film (short-end remnants from the movie industry) as a cheaper alternative for 35mm color negative still photography, and printed this onto 5283 color print film (same as movie prints) for 35mm slides.
I recently found a few boxes of these that I had shot back then (and stored under entirely careless, or Arrhenius/Murphy if you prefer, conditions). I am not good at evaluating color negatives by eye, but the positives were faded either to mutated colors or to almost nothing.
Even simple technologies can have amazingly short shelf lives under conditions of disuse. I recently turned on my stereo system after close to 3 years of not being used. The amplifier, CD player, and LP turntable all failed to operate. Part of this might have been due to de-formed electrolytic capacitors; these appear to have more-or-less repaired themselves after a couple of hours with the power turned on. Both the CD player and the turntable suffered additional electromechanical problems that required a combination of manual exercise and cleaning to rectify.
None of these devices have anywhere near the scary sophistication of a modern hard disk drive.
Seeing as I cannot remember what I last set my external firewall password to, imagine the additional challenge of future Hollywood being bitten deeply in the butt by present Hollywood's favored time-bombed destined-to-be-lost-art proprietary DRM technologies, with the keys long since dissipated in Hollywood's perennial miasma of mergers, acquisitions, lawsuits, cocaine, and personal vendettas.
I later was taken on a tour of a SAGE (air defense radar processing) installation with its massive AN/FSQ7 vacuum tube computer and CRT displays with their vastly Buck Rogers light pens.
I might still have a relic of the IBM vacuum tube era: a plug-in tube circuit module. This was a U-shaped metal frame containing a single socketed vacuum tube, some phenolic wafers that supported various resistors and capacitors, and a plug on the bottom.
Mine, if it still exists in a box in the garage, is no longer in original condition. I removed the original components, and built upon it a 12AX7-based audio modulator (Popular Electronics magazine project) for a HeNe laser (also a PE project). The modulator actually worked for a few minutes before a power supply capacitor shorted and smoked itself and the plate transformer.
My first paid job was operating and programming an IBM 1401. Its model 1311 "washing machine" removable pack disk drives stored 2,000,000 characters, or 2,980,000 in "track record" mode (if your program could afford the memory to read and write full tracks instead of 100 character sectors). The seek actuator was hydraulic, and there was usually a small pool of leaked oil at its base.
By contrast, in the U.S. there seems to be a lot of casual conversation and a tendency to escalate the volume as more people become enmeshed in the conversation.
I have shared 2 person closed offices with 1) a person who mumbled to himself in German, then 2) a person who constantly ate sunflower seeds and made weird moaning and smacking noises while doing it, along with shell cracking noises. Both drove me to distraction.
A very brief experience in a (very low wall) cube environment in India gave an interesting contrast. The work style appeared to be highly social, with 2 or more people very frequently clustered around one computer. People appeared to be disciplined or at least considerate, and kept the conversation volume level low.
I need total silence to retain enough concentration to work on difficult problems and to produce coherent written results. Conversation is an occasional part of the process, but for me it is much more the exception than the rule.
Also, I do not see how anyone can expect significant technical work to occur without whiteboards, and ones whose contents will remain undisturbed for days. I do not use these much myself, but there are times when they are essential, and some people use them constantly.
Notebooks are ergonomic catastrophes, and are a great way to lose work through breakage and theft.
There was a much more descriptive term in the '70s for the so-called open office. It was called a "bull pen". When I have an actual nightmare about working environments, around 70% of the time it takes place in a downwards extension of the classic gray linoleum-topped desk-matrix bull pen: a large room full of rows of those cheap long folding tables, with closely spaced computers atop them, and no permanent seat assignments.
People who make the decisions for these crappy environments typically operate in a sub-world saturated with conversation and bargaining. A "sustained effort" means exercising self-similar weekly, monthly, and quarterly rituals with minor variations.
This is a fundamentally different world than that of novel and deeply analytic problem solving in mathematics and code, requiring weeks, months, or longer.
http://www.jstage.jst.go.jp/article/elex/4/3/77/_pdf
This is not exactly the work referenced in the original article, but it is very likely related to it. Anything that requires a cell of isotopically weird (carbon 13) acetylene sounds fun to me.
The crucial element appears to be a highly stabilized laser that is used in the receiver as a local oscillator to recover (by optical heterodyne detection) a UHF RF carrier that carries the actual QAM.
I had read speculative/theoretical statements about optical heterodyne detection years ago (probably around '94). It might've taken this long to get a stable (and monochromatic) enough local oscillator to demonstrate it in a potentially useful state.
What is routinely done today in hybrid fiber/coaxial cable (HFC) cable TV systems, is to use linear RF-band, often 50-750MHz in 6MHz (North American standard) bands corresponding to television channels. Both 64- (6 bits/baud) and 256- (8 bits/baud) QAM modulation standards are used. 64-QAM has been around since maybe 1996.
256-QAM requires a better signal/noise ratio through the transmission path, and better A/D resolution and more demodulation work in the receiver. 256-QAM gives around 38.8Mb/s payload rate after subtracting TV standard (ITU J.83B) ECC and packet overheads. 256-QAM is seeing increasing use as better chip technology makes the demodulators cheap, as cable plant is upgraded to push fiber farther out toward the end subscribers with better signal quality.
700MHz / 6MHz = 116 TV channels * 38.8Mb/s = roughly 4.5Gb/s digital capacity for QAM on a 700MHz RF bandwidth. Again, this is done routinely today, except of course a TV receiver only selects and demodulates a single 6MHz channel at a time.
One could WDM a number of 700MHz RF ensembles onto a fiber, but this of course requires source lasers (ones designed for wideband linear modulation, or with $$$ external modulators) with precisely tuned and stabilized wavelengths, and corresponding optical splitter/filters, individual optical receivers for each wavelength, and RF-band demodulators for however many channels the RF band has been divided into.
Terabit through this conceptually straightforward WDM approach would require over 200 such optical carriers (a couple of racks of very expensive equipment. It's feasible, but not something you will have on the side of your house (even receive-only) in the near future.
Examining the price/capacity trendline on his slides, I projected that by perhaps 2009, they would be paying customers to take the drives.
This leads to one of three possible conclusions:
1) Disk drives contain something foul that someone is willing to pay to be rid of
or
2) The Bush administration subsidizes the disk drive industry (and its greatest consumption motivators: the porn and ripped music distribution industries) to make certain that new drives, all of which contain Super Secret Surveillance technology, are widely deployed
or
2) Disk drives are made of anti-petroleum.
Kodak's Spin Physics division introduced, I believe in 1986, the Ektapro 1000 high speed scientific imaging system, with an NMOS sensor.
"Staring focal plane array" (FPA) systems (typically infrared) for military use probably pre-date this and are comparable to digital cameras. Scanning FPA systems are earlier and might also qualify, depending upon where you care to draw the line.
In the lawyerly search for black-and-white distinguishing criteria for who is doing creative or managerial work vs. who is a mere crank-turning technician, government apparently looks to its own qualification criteria: immigration preference, and "qualified personnel" clauses from government contracting (a field where one finds that great exception, unionized engineers).
It could be argued that this has an effect of age discrimination, in that years ago it was much more common than now to be able to enter the computing field without having a CS degree, or any degree at all. It could be further argued that companies are quite willing to go along with this, because it provides a path to displace older and higher-priced IT workers (by reclassifying them to lower-paid status), while maintaining some defense against age discrimination claims.
At my former employer (Fortune 500 technology company), I was at the second-highest step on the technical career ladder (yes, we all know that ladder is built of smoke, supported by mirrors). After whatever lawyering fad resulted in the new spin on FLSA, the company issued HR policy that said in effect that I could not have been hired for any engineering position. Their interpretation of the computer-related-fields exemption included only management information systems and networks, and not product design and development engineering.
As might be expected, this company is a leader in H1B visa use, and in moving work offshore.
*MEOW* *swipe* [connection timed out]