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ref: -0 tags: US employment top 100 bar chart date: 11-12-2018 00:02 gmt revision:1 [0] [head]

After briefly searching the web, I could not find a chart of the top 100 occupations in the US. After downloading the data from the US Bureau of Labor Statistics, made this chart:

Click for full-size.

Surprising how very service heavy our economy is.

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ref: -0 tags: rogers thermal oxide barrier neural implants ECoG coating accelerated lifetime test date: 12-28-2017 02:29 gmt revision:0 [head]

PMID-27791052 Ultrathin, transferred layers of thermally grown silicon dioxide as biofluid barriers for biointegrated flexible electronic systems

  • Thermal oxide proved the superior -- by far -- water barrier for encapsulation.
    • What about the edges?
  • Many of the polymer barrier layers look like inward-rectifiers:
  • Extensive simulations showing that the failure mode is from gradual dissolution of the SiO2 -> Si(OH)4.
    • Even then a 100nm layer is expected to last years.
    • Perhaps the same principle could be applied with barrier metals. Anodization or thermal oxidation to create a thick, nonporous passivation layer.
    • Should be possible with Al, Ta...

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ref: Butovas-2007.04 tags: Butovas Schwarts ICMS stimulation rat barrel cortex date: 01-03-2012 06:55 gmt revision:2 [1] [0] [head]

PMID-17419757[0] Detection psychophysics of intracortical microstimulation in rat primary somatosensory cortex.

  • headposted rats, ICMS to barrel cortex
  • single pulse threshold = 2 nC, around the threshold for evocation of short-latency action potentials near an electrode.
  • one pulse saturated at 80% correct.
  • multiple pulses had a higher rate, though this saturated at 15 pulses.
  • double pulse optimal in terms of power / discrimination.

____References____

[0] Butovas S, Schwarz C, Detection psychophysics of intracortical microstimulation in rat primary somatosensory cortex.Eur J Neurosci 25:7, 2161-9 (2007 Apr)

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ref: Harris-2009.06 tags: Bartholow 1874 Mary experiment stimulation ICMS date: 12-29-2011 05:13 gmt revision:2 [1] [0] [head]

PMID-19286295[0] Probing the human brain with stimulating electrodes: The story of Roberts Bartholow’s (1874) experiment on Mary Rafferty

  • Excellent review / history.
  • Actual citation: Experimental investigations into the functions of the human brain" The American Journal of the medical Sciences 1874
  • Actual subject: Marry Rafferty
  • Around his time people were shifting from using intuition and observation to direct treatment to using empiricism & science, especially from work on laboratory animals.
  • One of the innovations that could not be tolerated by his colleagues was the "physiological investigations of drugs by the destruction of animal life." He was a bit of an outsider, and not terribly well liked.
  • Before then the cortex was seen to be insensitive to stimulation of any kind.
  • Ferrier 1974b: in the striatum all movements are integrated which are differentiated in the cortex" -- striatal stimulation produces general contraction, not specific contraction.
  • Ferrier 1873 was the first to discover that AC stimulation yielded more prolonged and natural movements than DC.
  • The Dura mater is extremely sensitive to pain.
  • Mary Rafferty seems to have had a tumor (he calls it an ulcer) in the meninges (epithelioma).
  • He probably spread infection into her brain through the stimulating needles.

____References____

[0] Harris LJ, Almerigi JB, Probing the human brain with stimulating electrodes: the story of Roberts Bartholow's (1874) experiment on Mary Rafferty.Brain Cogn 70:1, 92-115 (2009 Jun)

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ref: notes-0 tags: Barto Hierarchal Reinforcement Learning date: 02-17-2009 05:38 gmt revision:1 [0] [head]

Recent Advancements in Hierarchal Reinforcement Learning

  • RL with good function-approximation methods for evaluating the value function or policy function solve many problems yet...
  • RL is bedeviled by the curse of dimensionality: the number of parameters grows exponentially with the size of a compact encoding of state.
  • Recent research has tackled the problem by exploiting temporal abstraction - decisions are not required at each step, but rather invoke the activity of temporally extended sub-policies. This is somewhat similar to a macro or subroutine in programming.
  • This is fundamentally similar to adding detailed domain-specific knowledge to the controller / policy.
  • Ron Parr seems to have made significant advances in this field with 'hierarchies of abstract machines'.
    • I'm still looking for a cognitive (predictive) extension to these RL methods ... these all are about extension through programmer knowledge.
  • They also talk about concurrent RL, where agents can pursue multiple actions (or options) at the same time, and assess value of each upon completion.
  • Next are partially observable markov decision processes, where you have to estimate the present state (belief state), as well as a policy. It is known that and optimal solution to this task is intractable. They propose using Hierarchal suffix memory as a solution ; I can't really see what these are about.
    • It is also possible to attack the problem using hierarchal POMDPs, which break the task into higher and lower level 'tasks'. Little mention is given to the even harder problem of breaking sequences up into tasks.
  • Good review altogether, reasonable balance between depth and length.

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ref: notes-0 tags: grain protein growing framing feed oats alfalfa barley corn wheat date: 06-18-2008 15:14 gmt revision:0 [head]

I found this on my computer tucked away into a dusty corner. Such fascinating information should not be left hidden -