# C[omp]ute

Welcome to my blog, which was once a mailing list of the same name and is still generated by mail. Please reply via the "comment" links.

Always interested in offers/projects/new ideas. Eclectic experience in fields like: numerical computing; Python web; Java enterprise; functional languages; GPGPU; SQL databases; etc. Based in Santiago, Chile; telecommute worldwide. CV; email.

© 2006-2013 Andrew Cooke (site) / post authors (content).

## The Black Dork Lives!

From: andrew cooke <andrew@...>

Date: Thu, 24 Jul 2014 21:06:13 -0400

[Not a racial epithet]

http://imgur.com/a/0BHEE

On one of the Reddit bicycling groups there was a "discussion" about "dork
disks" - the plastic disks required by US law between cassette (rear gears)
and spokes:
(item 3 under "What are the requirements for chains and chain guards?").

The argument goes that a correctly adjusted derailleur does not need this
protection, and so "bike snobs" (they exist) remove the disk.

There are three counter-arguments to this:
1 - On a mountain bike it could still help save your wheel if the
derailleur gets knocked into the wheel.
2 - No-ones perfect; you could accidentally misadjust the mechanism
(one of my pedals came loose the other day!).
3 - Bike snobs?

I find 3 particularly convincing, but at the same time the disk does look
kinda ugly (it is, or was, a see-through piece of plastic).  So I decided to
paint it black.  This was pretty easy as I had an old can of black spray
enamel and the tools needed to take the cassette off (and so get at the disk).

The result is shown in the photos.  I like it.  I cleaned up the cassette when
I removed it, so it's back to silver, but it will be darker soon, as it gunks
up, and so the disk will look more "integrated".

Andrew

## Previous Entries

### The UN Requires Unaninmous Decisions

From: andrew cooke <andrew@...>

Date: Thu, 24 Jul 2014 20:56:12 -0400

http://f8wee1vvia32pdxo527grujy61.wpengine.netdna-cdn.com/wp-content/uploads/2014/07/UNvote.jpg

### LPIR - Steganography in Practice

From: andrew cooke <andrew@...>

Date: Sun, 20 Jul 2014 13:02:04 -0400

http://en.wikipedia.org/wiki/Low_probability_of_intercept_radar

From http://lists.randombit.net/pipermail/cryptography/2014-July/006673.html

Andrew

### How I Am 6

From: andrew cooke <andrew@...>

Date: Sat, 19 Jul 2014 15:26:32 -0400

http://acooke.org/cute/HowIAm0.html
http://acooke.org/cute/HowIAm20.html
http://acooke.org/cute/HowIAm30.html
http://acooke.org/cute/HowIAm40.html
http://acooke.org/cute/HowIAm50.html

Now 20.5 months from being diagnosed.  19.5 months on Betaferon.

In general, nothing particularly new.

Biggest problem has been tendonitis (right achilles), which is not a direct
result of the MS, but something I've struggled with for years, and exacerbated
by regular running (which *was* motivated by the MS - try to exercise every
non-injection day).

Physiotherapy, no walking, and reducing running distances failed to fix
things, so bought a bike to have an alternate method of exercise.  That
helped, but had to travel for work / parents which made things worse again.
Now back home and hope things will improve.  The bike is fun, but I am wary of
using even that too much.

This last week things have been weird.  I guess it's just a cycle of
re-mylenization (it could be progressive MS, but I don't really have the
cumulative evidence of things getting worse).  Random aches and twitching.
Yesterday I felt the strap of my bike helmet under the chin "for the first
time".  Today I seem to be more aware of a constriction around my chest (a
place where I've had symptoms before).

My right hand is very slightly better than before.  The best description now
is that it feels "tired" and "slightly stiff" with mild PN / waxiness in the
fingers.  Still some related numbness on the rght upper arm.

Under the thighs remains odd - an uncomfortable feeling when sitting.  I don't
think that has ever been OK.  Recently trousers round my thighs have felt
"odd".

But no clear new outbreak.  I continue to wait...

Hello to future self.  Keep on rockin'

Andrew

### Clear Explanation of Verizon / Level 3 / Netflix

From: andrew cooke <andrew@...>

Date: Thu, 17 Jul 2014 19:40:56 -0400

http://blog.level3.com/global-connectivity/verizons-accidental-mea-culpa/

In particular,

Andrew

### Teenage Girls

From: andrew cooke <andrew@...>

Date: Wed, 16 Jul 2014 20:03:15 -0400

http://www.polygon.com/2014/7/15/5897811/ninja-pizza-girl-teenage-girls-family-dev

Sounds awful.

Andrew

### Formalising NSA Attacks

From: andrew cooke <andrew@...>

Date: Thu, 10 Jul 2014 08:08:12 -0400

http://tools.ietf.org/html/draft-barnes-pervasive-problem-01

Is formalizing a word?  Anyway - a precise (ish) description of attacks from
Snowden.

Andrew

### Switching Brakes (Tektro Hydraulic)

From: andrew cooke <andrew@...>

Date: Sun, 6 Jul 2014 07:57:41 -0400

My new(ish) bike is an American import, which means that the right brake lever
controls the rear wheel.  UK bikes are reversed (right is front) which means
that instinctive braking tends to lock the rear (when you brake hard you need
to use the front, since that's where the weight is; for me that means using
the right hand which locks the rear instead; the instinct on locking the rear
is to release the left brake and apply more to the right...).

The brakes are hydraulic and contain a reservoir of oil on the "top" side of
the lever assembly.  This means that they cannot be simply disconnected from
the bars and swapped, as the reservoir would be upside down.

So instead, the hoses must be unscrewed and swapped.  To do this:

- Remove the front wheel (to be sure you don't get hydraulic oil on
the disks) and place a wedge between the brake pads so that they will
not close shut if the brake is applied.

- Slide off the plastic cover where the hose meets the lever assembly.
This will reveal an 8mm nut.

- Remove the grips from the handlebars, loosen the assemblies and slide
them off the bars.

- Carefully unscrew one hose from its assembly.  Make sure to keep the
connection point higher than the brake and, as soon as the two are
separate, keep both "pointing up" so that no oil escapes.

- Work out how to keep both "pointing up" while you separate the other
hose and assembly (I tucked the free hose behind the bars and balanced
the assembly on a nearby stone).

- Reconnect hoses and assemblies, swapped.

- Replace on bars, replace grips, and replace wheel.

All the above is pretty obvious.  The main point is that, at least for me, it
was possible without losing a significant amount of oil, and without
introducing air into the hydraulics.  The brakes worked just fine afterwards.

But I did have a hydraulics service kit with new oil read just in case.

Andrew

### Naim NAP 100 (Power Amp)

From: andrew cooke <andrew@...>

Date: Sat, 5 Jul 2014 20:05:34 -0400

Just connected up the new amp.  I haven't done any blind tests, but it does
seem to sound quite different to what we had before (Arcam Solo) - more
"bouncy" and better stereo imaging.

Here's the current setup:

Computer (mp3 via mpd/ncmpcpp)
|
+ Music Fidelity V-Link (USB buffer to optical)
|
+ Optical splitter
|
+ Audio-GD NFB3.1 (DAC)
|  |
|  + Music Fidelity V-Can (headphone amp)
|     |
|     + AKG K702
|     + AKG K550
|     + Sennhesier HD25-II
|     + Sennhesier HD555
|
+ AudioEngine D2 (wifi sender)
|
+ AudioEngine D2 (wifi receiver / DAC)
|  |
|  + Roksan Kandy K2 (integrated amplifier)
|     |
|     + ATC SCM7
|
+ AudioEngine D2 (wifi receiver / DAC)
|
|
+ Naim NAP 100 (power amp)
|
+ Speaker switch
|
+ Mission 700LE
+ B+W 602S2

The headphone amp and B+W speakers are in the office; Roksan and ATCs are in
the bedroom; ancient Missions in the kitchen and Quads in the living room
(there's a lot of cable hanging off the speaker switch).

Andrew

### AKG 550 First Impressions

From: andrew cooke <andrew@...>

Date: Sat, 28 Jun 2014 21:59:16 -0400

The bad news - on forst listen there seems to be an ugly emphasis in the upper
mids.  And it makes saxophones and trumpets grate.  Which is bad news if you
want to listen to jazz on these.

Also, when I ran a frequency scan, there's some weird unmatched jump to one
side in a narrow high frequency band (I guess around 1kHz).  I don't think
this is audible, and since I've never done the scan on any other headphones I
don't know jow unusual it is.  But it seemed odd.

In general, when I first listened to these (on very limited equipment - the
best source I have while travelling is an ASUS netbook) the music seemed flat
and unexciting.

The good news - now I'm getting used to them a little (an hour or two of
listening in) and they're sounding much better.  The bass isn't emphasized at
all, but it's certainly there (more so than the 702s).  The treble isn't
perfect (these are the closed headphones that are supposed to sound open and
then don't, imho) but it's perhaps better than other closed cans (it certainly
feels better than I remember of the HD25s).

The build quality is great (although really the headband is just a band of
thin, springy metal, when you look at it, the padding makes it seem solid) and
I have had no issues with getting a good seal (for the bass).  The isolation
is pretty good.  And it's comfortable (but people with small heads, try before
you buy; I have a large noggin and the band is hardly extended at all).

When I take them off, I notice the pleather is warm and a little sweaty.  But
I don't notice any heat when they're on (then again, it's bloody freezing here
in Yorkshire at the end of June).

And switching back to jazz now, the upper mids sound better.  It's amazing how
you ears / brain adapt.  I'm really having to strain to hear what seemed so
bad at first.  If I didn't know better I'd swear these needed to burn-in :o)

Imaging is retricted - everything is inside your head - but individual
instruments are nicely located.

Pootling through Kind of Blue on YouTube and this sounds pretty damn good.
Neutral, balanced, well-defined.  Only the very top end is missing space.

Andrew

### Facebook manipulates emotions (no really)

From: andrew cooke <andrew@...>

Date: Sat, 28 Jun 2014 11:38:43 -0400

The title sounds like a troll, but then when you think about it, is IS kinda
creepy.  Which makes more money for them?  Happy or sad users?  Maybe sad
people spend more to cheer themselves up?  If so, would that imply about

Andrew

### Map Reduce "No Longer Used" At Google

From: andrew cooke <andrew@...>

Date: Fri, 27 Jun 2014 03:17:31 -0400

Article has links to some interesting papers.  Basic idea is just that things
have become more general.

Andrew