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davepage

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Location: Baltimore, Maryland, USA

Remote: Yes

Willing to relocate: No

Technologies:

    Hardware: Instrumentation & conditioning, filtering, ADC/DAC, RF Applications (IEEE 802.15.4), phase locked loops, IGBT & SCR control, power supplies, microcontrollers, memory, peripherals, USB, Ethernet, EtherCAT, CAN, PCI, ISA, TEDS (IEEE 1451.4), UART, SPI, I2C, PWM, quadrature encoders, PID control, IIR/FIR filters, phase locked loops, synchronous detection, IMU, INS, optical sensors, cold gas thrusters, EMC, RFI

    Software: C++, C#, MATLAB; C; Python; VHDL, Verilog; Assembler; Familiar with Javascript, SQL, Visual Basic, UNIX shell and tools; Windows, QNX RTOS, Real Time Linux, bare metal; Eclipse, Visual Studio, TI Code Composer Studio, MPLab, GNU, Atmel Studio; Xilinx, Altera, OrCAD, Eagle CAD, LTSpice, git 
Résumé/CV: http://dave-page.com/cv

Email: hn@dave-page.com

Hi there! I am a very experienced embedded systems designer and manager with a proven track record delivering results. I can help define requirements, create an electronic design, write software, and build a conforming prototype.

The Boeing/Ethiopian ETH-2 bulletin quoted in the above linked AAIB preliminary report on page 33 says "Initially, higher control forces may be needed to overcome any stabilizer nose down trim already applied. Electric stabilizer trim can be used to neutralize control column pitch forces before moving the STAB TRIM CUTOUT switches to CUTOUT ..."

It does not appear to be "precisely" the procedure, in that sufficient nose up trim was not selected by the yoke manual trim switch prior to pulling the trim cutouts. And then they did not work the mechanical trim wheel hard enough to reset the residual nose down trim.

And, the crew left the power setting at climb throughout almost the entire sequence, so they oversped the airframe.

And, when they (against procedure) (apparently) turned the electric trim system back on, they did not use the yoke manual trim switch to fix the nose down trim problem -- which is a big mystery.

The MCAS design inhibits its FCC trim down output when manual trim is utilized. So, if they had just continuously pushed the nose up manual trim switch on the yoke until they got the trim to neutral, then pulled the cutout (either the first time or second time), the accident could have been avoided.

History shows this is not a good human factors design on the part of Boeing, but the crew does not look good, either, IMO.

Keeping things simple, if the input data SNR is, say, 16 bits, and the PID coefficients are 16 bits, then there is 32 bits of significand at the output of the control gain multipliers. For single precision float, this is truncated to 23 bits. So, the system may settle when the transducer input is near zero (and the exponent can scale down to maintain sufficient precision), but then fail to settle well at the ends of the transducer range (where the transducer input is near +/-2^15 and the exponent in the single needs to stay high to avoid saturation). Also, consider the numerical integrator is running an infinite series of adds, so therein lies a trap for error growth, as well.

I have made this mistake before, and the sometimes strange control behavior can be frustrating. Considering the small performance penalty for using doubles on modern hardware, it is excellent advice.

Visa Systems Issues 11 years ago

Of course I am a hypocrite. My partner wants to visit the US; I would prefer to live elsewhere. But, sometimes compromise is needed in relationships.

'failed state' is certainly hyperbole here -- there are large elements of society which continue to function, despite the problems at the national government level. It would truly be a failed state if, for example, the national government's performance level were propagated to the whole society.

Visa Systems Issues 11 years ago

Took 14 months with Congressional intervention just to get my partner a immigrant visa -- which is presumably the easiest.

America has been so obsessed with thinking of itself as the "best country in the world!(TM)" for so long, it has meanwhile regressed into a failed state.

Well, maybe. From a regulatory perspective, the radio users have more FCC clout than insouciant interference sources like Comcast and TW, neglecting whatever regulatory capture may exist.

Shortwave listeners and amateur radio folks were upset about powerline internet: http://www.arrl.org/broadband-over-powerline-bpl

From an engineering standpoint, sending broadband over the power infrastructure is seriously ugly, because the SNR is poor, shielding is poor, and spectral distortion is high. Power lines were never designed to be constant impedance, low loss and shielded for broadband frequencies. Due to all the impairments, the transmit power must be relatively high, and coupled with the poor shielding, interference with legitimate radio users is inevitable.

Sure... the Russians and Chinese (not the same people) just happened to simultaneously break some strong encryption, and the UK just happened to discover this somehow, before anything significant happened. Perfectly propaganda.

Perhaps the next press release will claim, 'paying taxes reduces the risk of death by 42%!'

I agree. More layers of complexity than short term memory slots is a mandatory property of belief systems -- as more effort will be required to find the contradictions then is likely to be allocated.

And certainly handling such individuals with kid gloves is important to mitigate the intransigence reflex. I only ask because I wish to discover some more effective strategy to aid some of the more zealous individuals to improve their moral consistency. Fear is far more powerful than reason, however.

In terms of moral introspection, I perceive a continuum of information quality from vague suspicion to almost complete certainty. Morally, I would have a very, very difficult time making life-changing affirmative moral arguments to complete strangers without almost complete certainty.

And, I could never, never ascribe almost complete certainty to a piece of information not complying with the vacuum intellect test (i.e. could an intelligent person not exposed to culture reasonably be expected to arrive at a similar conclusion, if given sufficient resources for independent experimentation).

So, quantum mechanics, as weird as it is, could pass the vacuum intellect test. Could I personally see a vacuum intellect reinventing the tenets of Christianity including the concept of hell? That seems completely implausible to me. Sure, one could argue divine intervention (again) -- but that violates the vacuum constraint.

So, question: By what moral thesis does one permit one's self to venture out into the world and attempt to convince other people to redirect their limited resources onto something which is not almost completely certain?

"Illegal" and "wrong" are not in any way related. All spy agencies conduct activities which are clearly illegal under the laws of their target countries. But are these activities always "wrong?" Conversely, spy agencies may conduct activities which are legal under their own laws, but are morally wrong -- harassment of MLK, for example.

And "unambiguously legal" is overselling the point: PPD-20 includes offensive capabilities amounting to acts of war -- which would presumably be illegal absent congressional approval. China surveillance includes illegal surveillance of US nationals and well as mass surveillance, which is arguably inappropriate policy. Tempora is a program conducted by the UK -- arguably illegal as signatory to EU treaty. Spying on Germany is likely to support economic espionage, which would be illegal under WTO treaty, etc. Al Jezeera is a journalist organization, which provides a useful Arab propaganda counterpoint to US propaganda, and is not itself a sponsor or advocate of terrorism. The various spying methods exposed are executive overviews and lack sufficient technical detail for implementation, and are thus appropriate for public policy discussion.

The US state security apparatus is also not elected -- yet it clearly does control policy through overclassification and outright misrepresentation of its activities to congressional oversight.

Were Mr. Snowden's actions illegal? Yes, clearly, but that is a question of no meaningful value in this context, as most NSA activity is illegal somewhere, and some NSA and FBI activity is clearly illegal within the US.

Were these actions wrong? That remains to be seen.

Even if they were wrong, is there a net moral benefit which could excuse the costs? That is a complicated question. Do the fruits of NSA, CIA and FBI espionage achieve their stated goals? Is US foreign policy successful? Does the US reliably achieve its military objectives?

So, rather than yet again repeating the mistakes made over the last 100 years -- with some exceptions, an otherwise disgraceful litany of paranoia and short-sighted pragmatism -- perhaps it is a good time to reexamine politically whether foreign policy as practiced by the US is appropriate and efficacious. The responsibility for this interminable chain of dismal failures must be accepted by the US government and US electorate as a whole. The status quo -- mindless subservience to nationalism, patriotism, and religion along with a generous dose of political amnesia -- is completely unjustified at this point.

This discussion cannot ever fully occur when the mechanisms informing that foreign policy are forever hidden from political debate by a veil of overclassification motivated by criminal activity.

Mr. Snowden has caused that debate to begin -- his stated intent. One could therefore reasonably conclude his actions are moral and justified as well as illegal under US law. US law is therefore the problem, not Mr. Snowden.

Essentially the American state religion to which your refer is largely predicated on the concept that any law may be ignored by those in power so long as the intent is to produce "good outcomes" for some state perception of good. (i.e. 'the constitution is not a suicide pact' or read "Enemies: A History of the FBI")

Law (so far) is merely stains on paper until interpreted by the mind of an individual in some context (time, place, society). Societal context is some collective consensus over right and wrong -- some popular mush of common sense, the influence of which can be seen in the evolution of, for example, supreme court decisions over socially controversial issues. Where large numbers of individuals subscribe to a particular set of beliefs about what the law is, and proceed to act accordingly, a very convincing illusion of government emerges. And one may refer to this as a state religion in the sense it is entirely an emergent property of belief rather than reality.

Thus, absolute law is a myth. Pardons are an outlet for the elected leadership to short-circuit the legal process when, in a given instance, punishment is perceived to exceed the crime. It is thus arguably irrational to assert that a pardon is premature in the Snowden case, considering the outcome thus far.

Of course, those capable of issuing such pardons are themselves true believers. Snowden has committed blasphemy against the state religion. Thus a pardon can only occur should some popular unrest threaten those in power.

Is there something the US did right which Europe did not? Not sure what that might be. The VSB TV standard here is junk compared to DVB. We're stuck with VSB, because the incumbent broadcasters couldn't see past the few years of the transition period. And it didn't solve the co-channel interference, anyway.

from the perspective of people who live near airfields.

Things more annoying than airplane noise: * People who voluntarily choose to live near airports (which predictably have associated airplane noise), then complain about it. * The ubiquitous, intentionally loud motorcycles (at closest approach, much louder than any small airplane, due to power law d^-2), which all get a free pass for some bizarre cultural reason, and are largely inescapable.

Some of the airplane noise perception problem is jealousy, and is easy to fix: go down to the airport, chat someone up, and they'll give you a ride.

Is it not interesting that Mr. Obama evolved from "Transparency promotes accountability and provides information for citizens about what their government is doing," to "The administration’s war on leaks and other efforts to control information are the most aggressive I’ve seen since the Nixon administration" [1]?

What could have caused this?

[0] http://www.whitehouse.gov/the_press_office/TransparencyandOp... [1] http://cpj.org/reports/2013/10/obama-and-the-press-us-leaks-...

Remote in the sense that a local assembler would be on the developer's system, and remote assembler is on the end user's system. Using this lib, the developer uses C++ as if it were metacode or a macro system to then emit machine code instructions on demand. This will presumably then execute faster than plain C++ in certain applications.

I can think of several interesting applications for this, such as text search.

What is the practical benefit of a back yard pool (drowning apparatus), beer stein (poisoning apparatus), or a sports car (trauma apparatus)?

[I assume this must be a troll, since if this were taken to its logical conclusion, it advocates a Soviet style command and control society. No laughing, smiling, or running with scissors allowed.]

New Zealand's North Island has a similar problem. A typical house has cheap construction with thin exterior walls, unfinished crawl space with exposed soil, no insulation and no heat pump. Coupled with a damp climate 5-25C, in the winter one gets heavy condensation, black mold, chills, and the fingers don't work.

I bumped into a guy here from Northern Germany who said he's never been so cold as in a kiwi house in the winter.

The NZ government is trying to change minds, but I still see houses going up with empty wall cavities and no air barrier. But then, the natives wear shorts and tees outside in 5 degree weather all winter. So, maybe its just me.

Yet, to "build a better society" is a just euphemism for "build a better government." Empirically, governments organize themselves just as corporations: cult-like, soulless gangs which exist to enrich the wealthy elites and treat humanity as just "collateral damage." In fact, government invented the term of art.

The relative advantage of corporations, however, is one can choose to quit. Or choose to not buy their product. No one "has to have" an ipad or other such nonsense. No such option exists with regards to government. Voting has negligible effect and emmigration can only offer a least-worst improvement.