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Ben Martin: Terry is getting In-Terry-gence.

Thu, 2014-08-28 22:15
I had hoped to use a quad core ARM machine running ROS to spruce up Terry the robot. Performing tasks like robotic pick and place, controlling Tiny Tim and autonomous "docking". Unfortunately I found that trying to use a Kinect from an ARM based Linux machine can make for some interesting times. So I thought I'd dig at the ultra low end Intel chipset "SBC". The below is a J1900 Atom machine which can have up to 8Gb of RAM and sports the features that one expects from a contemporary desktop machine, Gb net, USB3, SATA3, and even a PCI-e expansion.





A big draw to this is the "DC" version, which takes a normal laptop style power connector instead of the much larger ATX connectors. This makes it much simpler to hookup to a battery pack for mobile use. The board runs nicely from a laptop extension battery, even if the on button is a but funky looking. On the left is a nice battery pack which is running the whole PC.



An interesting feature of this motherboard is no LED at all. I had sort of gotten used to Intel boards having blinks and power LEDs and the like.

There should be enough CPU grunt to handle the Kinect and start looking at doing DSLAM and thus autonomous navigation.

Andrew Pollock: [life] Day 211: A trip to the museum with Megan and a swim assessment

Thu, 2014-08-28 21:25

Today was a nice full day. It was go go go from the moment my feet hit the floor, though

I had a magnificent 9 hours of uninterrupted sleep courtesy of a sleeping pill, some pseudoephedrine and a decongestant spray.

I started off with a great yoga class, and then headed over to Sarah's to pick up Zoe. The traffic was phenomenally bad on the way there, and I got there quite late, so I offered to drop Sarah at work on the way back to my place, since I had no particular schedule.

After I'd dropped Sarah off, I was pondering what to do today, as the weather looked a bit dubious. I asked Zoe if she wanted to go to the museum. She was keen for that, and asked if Megan could come too, so I called up Jason on the way home to see she wanted to come with us, and directly picked her up on the way home.

We briefly stopped at home to grab my Dad Bag and some snacks, and headed to the bus stop. We managed to walk (well, make a run for) straight onto the bus and headed into the museum.

The Museum and the Sciencecentre are synonymous to Zoe, despite the latter requiring admission (we've got an annual membership). In trying to use my membership to get a discounted Sciencecentre ticket for Megan, I managed to score a free family pass instead, which I was pretty happy about.

We got into the Sciencecentre, which was pretty busy with a school excursion, and girls started checking it out. The problem was they both wanted to call the shots on what they did and didn't like not getting their way. Once I instituted some turn-taking, everything went much more smoothly, and they had a great time.

We had some lunch in the cafe and then spent some more time in the museum itself before heading for the bus. We narrowly missed the bus 30 minutes earlier than I was aiming for, so I asked the girls if they wanted to take the CityCat instead. Megan was very keen for that, so we walked over to Southbank and caught the CityCat instead.

I was half expecting Zoe to want to be carried back from the CityCat stop, but she was good with walking back. Again, some turn taking as to who was the "leader" walking back helped keep the peace.

I had to get over to Chandler for Zoe's new potential swim school to assess her for level placement, so I dropped Megan off on the way, and we got to the pool just in time.

Zoe did me very proud and did a fantastic job of swimming, and was placed in the second-highest level of their learn to swim program. We also ran into her friend from Kindergarten, Vaeda, who was killing time while her brother had a swim class. So Zoe and Vaeda ended up splashing around in the splash pool for a while after her assessment.

Once I'd managed to extract Zoe from the splash pool, and got her changed, we headed straight back to Sarah's place to drop her off. So we pretty much spent the entire day out of the house. Zoe and Megan had a good day together, and I managed to figure out pretty quickly how to keep the peace.

Richard Jones: When testing goes bad

Thu, 2014-08-28 18:25

I've recently started working on a large, mature code base (some 65,000 lines of Python code). It has 1048 unit tests implemented in the standard unittest.TestCase fashion using the mox framework for mocking support (I'm not surprised you've not heard of it).

Recently I fixed a bug which was causing a user interface panel to display when it shouldn't have been. The fix basically amounts to a couple of lines of code added to the panel in question:

+ def can_access(self, context): + # extend basic permission-based check with a check to see whether + # the Aggregates extension is even enabled in nova + if not nova.extension_supported('Aggregates', context['request']): + return False + return super(Aggregates, self).can_access(context)

When I ran the unit test suite I discovered to my horror that 498 of the 1048 tests now failed. The reason for this is that the can_access() method here is called as a side-effect of those 498 tests and the nova.extension_supported (which is a REST call under the hood) needed to be mocked correctly to support it being called.

I quickly discovered that given the size of the test suite, and the testing tools used, each of those 498 tests must be fixed by hand, one at a time (if I'm lucky, some of them can be knocked off two at a time).

The main cause is mox's mocking of callables like the one above which enforces the order that those callables are invoked. It also enforces that the calls are made at all (uncalled mocks are treated as test failures).

This means there is no possibility to provide a blanket mock for the "nova.extension_supported". Tests with existing calls to that API need careful attention to ensure the ordering is correct. Tests which don't result in the side- effect call to the above method will raise an error, so even adding a mock setup in a TestCase.setUp() doesn't work in most cases.

It doesn't help that the codebase is so large, and has been developed by so many people over years. Mocking isn't consistently implemented; even the basic structure of tests in TestCases is inconsistent.

It's worth noting that the ordering check that mox provides is never used as far as I can tell in this codebase. I haven't sighted an example of multiple calls to the same mocked API without the additional use of the mox InAnyOrder() modifier. mox does not provide a mechanism to turn the ordering check off completely.

The pretend library (my go-to for stubbing) splits out the mocking step and the verification of calls so the ordering will only be enforced if you deem it absolutely necessary.

The choice to use unittest-style TestCase classes makes managing fixtures much more difficult (it becomes a nightmare of classes and mixins and setUp() super() calls or alternatively a nightmare of mixin classes and multiple explicit setup calls in test bodies). This is exacerbated by the test suite in question introducing its own mock-generating decorator which will generate a mock, but again leaves the implementation of the mocking to the test cases. py.test's fixtures are a far superior mechanism for managing mocking fixtures, allowing simpler, central creation of mocks and overriding of them through fixture dependencies.

The result is that I spent some time working through some of the test suite and discovered that in an afternoon I could fix about 10% of the failing tests. I have decided that spending a week fixing the tests for my 5 line bug fix is just not worth it, and I've withdrawn the patch.

Andrew Pollock: [life] Day 210: Running and a picnic, with a play date and some rain

Wed, 2014-08-27 18:25

I had a rotten night's sleep last night. Zoe woke up briefly around midnight wanting a cuddle, and then I woke up again at around 3am and couldn't get back to sleep. I surprised I'm not more trashed, really.

It was a nice day today, so I made a picnic lunch, and we headed out to Minnippi Parklands to do a run with Zoe in the jogging stroller. It was around 10am by the time we arrived, and I had grand plans of running 10 km. I ran out of steam after about 3.5 km, conveniently at the "Rocket Park" at Carindale, which Zoe's been to a few times before.

So we stopped there for a bit of a breather, and then I ran back again for another 3 km or so, in a slightly different route, before I again ran out of puff, and walked the rest of the way back.

We then proceeded to have our picnic lunch and a bit of a play, before I dropped her off at Megan's house for a play while I chaired the PAG meeting at Kindergarten.

After that, and extracting Zoe, which is never a quick task, we headed home to get ready for swim class. It started to rain and look a bit thundery, and as we arrived at swim class we were informed that lessons were canceled, so we turned around and headed back home.

Zoe watched a bit of TV and then Sarah arrived to pick her up. I'm going to knock myself out with a variety of drugs tonight and hope I get a good night's sleep with minimum of cold symptoms.

Maxim Zakharov: Central Sydney WordPress Meetup: E-mail marketing

Wed, 2014-08-27 01:25

Andrew Beeston from Clicky! speaks about email marketing at Central Sydney WordPress meetup:

Andrew Pollock: [life] Day 209: Startup stuff, Kindergarten, tennis and a play date

Tue, 2014-08-26 21:25

Last night was not a good night for sleep. I woke up around 12:30am for some reason, and then Zoe woke up around 2:30am (why is it always 2:30am?), but I managed to get her to go back to bed in her own bed. I was not feeling very chipper this morning.

Today was photo day at Kindergarten, so I spent some extra time braiding Zoe's hair (at her request) before we headed to Kindergarten.

When I got home, I got stuck into my real estate license assessment and made a lot of progress on the current unit today. I also mixed in some research on another idea I'm running with at the moment, which I'm very excited about.

I biked to Kindergarten to pick Zoe up, and managed to get her all sorted out in time for her tennis class, and she did the full class without any interruptions.

After tennis, we went to Megan's house for a bit. As we were leaving, her neighbour asked if we could help video one of her daughters doing the ALS ice bucket challenge thing, so we got a bit waylaid doing that, before we got home.

I managed to get Zoe down to bed a bit early tonight. My cold is really kicking my butt today. I hope we both sleep well tonight.

BlueHackers: About your breakfast

Tue, 2014-08-26 12:00

We know that eating well (good nutritional balance) and at the right times is good for your mental as well as your physical health.

There’s some new research out on breakfast. The article I spotted (Breakfast no longer ‘most important meal of the day’ | SBS) goes a bit popular and funny on it, so I’ll phrase it independently in an attempt to get the real information out.

One of the researchers makes the point that skipping breakfast is not the same as deferring. So consider the reason, are you going to eat properly a bit later, or are you not eating at all?

When you do have breakfast, note that really most cereals contain an atrocious amount of sugar (and other carbs) that you can’t realistically burn off even with a hard day’s work. And from my own personal observation, there’s often way too much salt in there also. Check out Kellogg’s Cornflakes for a neat example of way-too-much-salt.

Basically, the research comes back to the fact that just eating is not the point, it’s what you eat that actually really does matter.

What do you have for breakfast, and at what point/time in your day?

Tridge on UAVs: APM:Rover 2.46 released

Tue, 2014-08-26 08:34

The ardupilot development team is proud to announce the release of version 2.46 of APM:Rover. This is a major release with a lot of new features and bug fixes.



This release is based on a lot of development and testing that happened prior to the AVC competition where APM based vehicles performed very well.



Full changes list for this release:

  • added support for higher baudrates on telemetry ports, to make it easier to use high rate telemetry to companion boards. Rates of up to 1.5MBit are now supported to companion boards.
  • new Rangefinder code with support for a wider range of rangefinder types including a range of Lidars (thanks to Allyson Kreft)
  • added logging of power status on Pixhawk
  • added PIVOT_TURN_ANGLE parameter for pivot based turns on skid steering rovers
  • lots of improvements to the EKF support for Rover, thanks to Paul Riseborough and testing from Tom Coyle. Using the EKF can greatly improve navigation accuracy for fast rovers. Enable with AHRS_EKF_USE=1.
  • improved support for dual GPS on Pixhawk. Using a 2nd GPS can greatly improve performance when in an area with an obstructed view of the sky
  • support for up to 14 RC channels on Pihxawk
  • added BRAKING_PERCENT and BRAKING_SPEEDERR parameters for better breaking support when cornering
  • added support for FrSky telemetry via SERIAL2_PROTOCOL parameter (thanks to Matthias Badaire)
  • added support for Linux based autopilots, initially with the PXF BeagleBoneBlack cape and the Erle robotics board. Support for more boards is expected in future releases. Thanks to Victor, Sid and Anuj for their great work on the Linux port.
  • added StorageManager library, which expands available FRAM storage on Pixhawk to 16 kByte. This allows for 724 waypoints on Pixhawk.
  • improved reporting of magnetometer and barometer errors to the GCS
  • fixed a bug in automatic flow control detection for serial ports in Pixhawk
  • fixed use of FMU servo pins as digital inputs on Pixhawk
  • imported latest updates for VRBrain boards (thanks to Emile Castelnuovo and Luca Micheletti)
  • updates to the Piksi GPS support (thanks to Niels Joubert)
  • improved gyro estimate in DCM (thanks to Jon Challinger)
  • improved position projection in DCM in wind (thanks to Przemek Lekston)
  • several updates to AP_NavEKF for more robust handling of errors (thanks to Paul Riseborough)
  • lots of small code cleanups thanks to Daniel Frenzel
  • initial support for NavIO board from Mikhail Avkhimenia
  • fixed logging of RCOU for up to 12 channels (thanks to Emile Castelnuovo)
  • code cleanups from Silvia Nunezrivero
  • improved parameter download speed on radio links with no flow control



Many thanks to everyone who contributed to this release, especially Tom Coyle and Linus Penzlien for their excellent testing and feedback.



Happy driving!

Tridge on UAVs: APM:Plane 3.1.0 released

Tue, 2014-08-26 07:33

The ardupilot development team is proud to announce the release of version 3.1.0 of APM:Plane. This is a major release with a lot of new features and bug fixes.



The biggest change in this release is the addition of automatic terrain following. Terrain following allows the autopilot to guide the aircraft over varying terrain at a constant height above the ground using an on-board terrain database. Uses include safer RTL, more accurate and easier photo mapping and much easier mission planning in hilly areas.



There have also been a lot of updates to auto takeoff, especially for tail dragger aircraft. It is now much easier to get the steering right for a tail dragger on takeoff.



Another big change is the support of Linux based autopilots, starting with the PXF cape for the BeagleBoneBlack and the Erle robotics autopilot.



Full list of changes in this release

  • added terrain following support. See http://plane.ardupilot.com/wiki/common- ... following/
  • added support for higher baudrates on telemetry ports, to make it easier to use high rate telemetry to companion boards. Rates of up to 1.5MBit are now supported to companion boards.
  • added new takeoff code, including new parameters TKOFF_TDRAG_ELEV, TKOFF_TDRAG_SPD1, TKOFF_ROTATE_SPD, TKOFF_THR_SLEW and TKOFF_THR_MAX. This gives fine grained control of auto takeoff for tail dragger aircraft.
  • overhauled glide slope code to fix glide slope handling in many situations. This makes transitions between different altitudes much smoother.
  • prevent early waypoint completion for straight ahead waypoints. This makes for more accurate servo release at specific locations, for applications such as dropping water bottles.
  • added MAV_CMD_DO_INVERTED_FLIGHT command in missions, to change from normal to inverted flight in AUTO (thanks to Philip Rowse for testing of this feature).
  • new Rangefinder code with support for a wider range of rangefinder types including a range of Lidars (thanks to Allyson Kreft)
  • added support for FrSky telemetry via SERIAL2_PROTOCOL parameter (thanks to Matthias Badaire)

    added new STAB_PITCH_DOWN parameter to improve low throttle behaviour in FBWA mode, making a stall less likely in FBWA mode (thanks to Jack Pittar for the idea).
  • added GLIDE_SLOPE_MIN parameter for better handling of small altitude deviations in AUTO. This makes for more accurate altitude tracking in AUTO.
  • added support for Linux based autopilots, initially with the PXF BeagleBoneBlack cape and the Erle robotics board. Support for more boards is expected in future releases. Thanks to Victor, Sid and Anuj for their great work on the Linux port. See http://diydrones.com/profiles/blogs/fir ... t-on-linux for details.
  • prevent cross-tracking on some waypoint types, such as when initially entering AUTO or when the user commands a change of target waypoint.
  • fixed servo demo on startup (thanks to Klrill-ka)
  • added AFS (Advanced Failsafe) support on 32 bit boards by default. See http://plane.ardupilot.com/wiki/advance ... iguration/
  • added support for monitoring voltage of a 2nd battery via BATTERY2 MAVLink message
  • added airspeed sensor support in HIL
  • fixed HIL on APM2. HIL should now work again on all boards.
  • added StorageManager library, which expands available FRAM storage on Pixhawk to 16 kByte. This allows for 724 waypoints, 50 rally points and 84 fence points on Pixhawk.
  • improved steering on landing, so the plane is actively steered right through the landing.
  • improved reporting of magnetometer and barometer errors to the GCS
  • added FBWA_TDRAG_CHAN parameter, for easier FBWA takeoffs of tail draggers, and better testing of steering tuning for auto takeoff.
  • fixed failsafe pass through with no RC input (thanks to Klrill-ka)
  • fixed a bug in automatic flow control detection for serial ports in Pixhawk
  • fixed use of FMU servo pins as digital inputs on Pixhawk
  • imported latest updates for VRBrain boards (thanks to Emile Castelnuovo and Luca Micheletti)
  • updates to the Piksi GPS support (thanks to Niels Joubert)
  • improved gyro estimate in DCM (thanks to Jon Challinger)
  • improved position projection in DCM in wind (thanks to Przemek Lekston)
  • several updates to AP_NavEKF for more robust handling of errors (thanks to Paul Riseborough)
  • improved simulation of rangefinders in SITL
  • lots of small code cleanups thanks to Daniel Frenzel
  • initial support for NavIO board from Mikhail Avkhimenia
  • fixed logging of RCOU for up to 12 channels (thanks to Emile Castelnuovo)
  • code cleanups from Silvia Nunezrivero
  • improved parameter download speed on radio links with no flow control

Many thanks to everyone who contributed to this release, especially our beta testers Marco, Paul, Philip and Iam.



Happy flying!

Andrew Pollock: [life] Day 208: Kindergarten, running, insurance assessments, home improvements, BJJ and a babyccino

Mon, 2014-08-25 21:25

Today was a pretty busy day. I started off with a run, and managed to do 6 km this morning. I feel like I'm coming down with yet another cold, so I'm happy that I managed to get out and run at all, let alone last 6 km.

Next up, I had to get the car assessed after a minor rear-end collision it suffered on Saturday night (nobody was hurt, I wasn't at fault). I was really impressed with NRMA Insurance's claim processing, it was all very smooth. I've since learned that they even have a smartphone app for ensuring that one gets all the pertinent information after an accident.

I dropped into Bunnings on the way home to pick up a sliding rubbish bin. I've been wanting one of these ever since I moved into my place, and finally got around to doing it. I also grabbed some LED bulbs from Beacon.

After I got home, I spent the morning installing and reinstalling the rubbish bin (I suck at getting these things right first go) and swapping light bulbs around. Overall, it was a very satisfying morning scratching a few itches around the house that had been bugging me for a while.

I biked over to Kindergarten for pick up again, and we biked back home and didn't have a lot of time before we had to head out for Zoe's second freebie Brazilian Jiu-Jitsu class. This class was excellent, there were 8 kids in total, and 2 other girls. Zoe got to do some "rolling" with a partner. It was so cute to watch. They just had to try and block each other from touching their knees, and if they failed, they had to drop to the floor and hop back up again. For each of Zoe's partners they were very civilized and took turns at failing to block.

Zoe was pretty tired after the class. It was definitely the most strenuous class she's had to date, and she briefly fell asleep in the car on the way home. We had to make a stop at the Garage to grab some mushrooms for the mushroom soup we were making for dinner.

Zoe helped me make the mushroom soup, and after dinner to popped out for a babyccino. It's been a while since we've had a post-dinner one, and it was nice to do it again. We also managed to get through the entire afternoon without and TV, which I thought was excellent.

Gary Pendergast: My Media Server

Mon, 2014-08-25 15:26

Over the years, I’ve experimented with a bunch of different methods for media servers, and I think I’ve finally arrived at something that works well for me. Here are the details:

The Server

An old Dell Zino HD I had lying around, running Windows 7. Pretty much any server will be sufficient, this is just the one I had available. Dell doesn’t sell micro-PCs anymore, so just choose your favourite brand that sells something small and with low power requirements. The main things you need from it are a reasonable processor (fast enough to handle transcoding a few video streams in at least realtime), and lots of HD space. I don’t bother with RAID, because I won’t be sad about losing videos that I can easily re-download (the internet is my backup service).

Downloading

I make no excuses, nor apologies for downloading movies and TV shows in a manner that some may describe as involving “copyright violation”.

If you’re in a similar position, there are plenty of BitTorrent sites that allow you register and add videos to a personal RSS feed. Most BitTorrent clients can then subscribe to that feed, and automatically download anything added to it. Some sites even allow you to subscribe to collections, so you can subscribe to a TV show at the start of the season, and automatically get new episodes as soon as they arrive.

For your BitTorrent client, there are two features you need: the ability to subscribe to an RSS feed, and the ability to automatically run a command when the download finishes. I’ve found qBittorrent to be a good option for this.

Sorting

Once a file is downloaded, you need to sort them. By using a standard file layout, you have a much easier time of loading them into your media server later. For automatically sorting your files when they download, nothing compares to the amazing FileBot, which will automatically grab info about the download from TheMovieDB or TheTVDB, and pass it onto your media server. It’s entirely scriptable, but you don’t need to worry about that, because there’s already a great script to do all this for you, called Advanced Media Server (AMC). The initial setup for this was a bit annoying, so here’s the command I use (you can tweak the file locations for your own server, and you’ll need to fix the %n if you use something other than qBittorent):

"C:/Program Files/FileBot/filebot" -script fn:amc --output "C:/Media/Other" --log-file C:/Media/amc.log --action hardlink --conflict override -non-strict --def "seriesFormat=C:/Media/TV/{n}/{'S'+s}/{fn}" "movieFormat=C:/Media/Movies/{n} {y}/{fn}" excludeList=C:/Media/amc-input.txt plex=localhost "ut_dir=C:/Media/Downloads/%n" "ut_kind=multi" "ut_title=%n" Media Server

Plex is the answer to this question. It looks great, it’ll automatically download extra information about your media, and it has really nice mobile apps for remote control. Extra features include offline syncing to your mobile device, so you can take your media when you’re flying, and Chromecast support so you can watch everything on your TV.

The Filebot command above will automatically tell Plex that a new file has arrived, which is great for if you choose to have your media stored on a NAS (Plex may not be able to automatically watch a directory on a NAS for when new files are added).

Backup

Having a local server is great for keeping a local backup of things that do matter – your photos and documents, for example. I use CrashPlan to sync my most important things to my server, so I have a copy immediately available if my laptop dies. I also use CrashPlan’s remote backup service to keep an offsite backup of everything.

Conclusion

While I’ve enjoyed figuring out how to get this all working smoothly, I’d love to be able to pay a monthly fee for an Rdio or Spotify style service, where I get the latest movies and TV shows as soon as they’re available. If you’re wondering what your next startup should be, get onto that.

Mark Greenaway: Guitar

Mon, 2014-08-25 01:26
Does anyone still blog? It seems nearly everyone has moved onto Twitter/Facebook. I miss being able to express thoughts in more than 160 characters.



I went to a picnic recently, and some people were passing a steel string guitar around. I'm not a good acoustic player, but it was fun so I had a bash. Someone played Under The Bridge, and took liberties with the chord voicings. So I was inspired to pick up my guitar and work through the official transcription, which I own. While the basic form of the song is pretty simple, as you can hear, the clever part is the choice of chord voicings and fills. I'll be practicing that one for a while.



I've also started over working through the Berklee method books, starting at Volume 2. I learned by playing by ear and memorising, so sight reading is still something I'm getting used to, and sometimes I'm not disciplined enough to do it properly. But I'm getting better at that. I'll be so happy when I start to get good at position playing.

Mark Greenaway: Physiotherapy

Mon, 2014-08-25 01:26

I'm at Elevate in Sydney CBD. For a long time, I've struggled with flexibility issues, and I began to think something must be wrong. It turned out something is wrong-I have a minor skeletal deformity in my left hip joint, and my muscles have developed in a strangely imbalanced way to compensate. Except it isn't working, I have severely reduced range of motion and had chronic pain in my left hip joint.

My Physio thinks he can correct the problem, but it's going to take a while. So I'll be off training for at least six weeks, and more likely two months or more. But it will be worth it if my joint pain goes away and I can move like the other people my judo class.

Posted via LiveJournal app for iPhone.

Mark Greenaway

Mon, 2014-08-25 01:26
"Curiously enough, the only thing that went through the mind of the bowl of petunias as it fell was 'Oh no, not again.'" - Hitchhiker's Guide to the Galaxy.

Mark Greenaway: One for the stats nerds

Mon, 2014-08-25 01:26
At USyd, we did all our stats in R. Now I'm working at the Department of Health, and we do most of our stats in SAS. SAS is pretty different to R, and so I've needed to work hard to try to learn it.



This is a rite of passage that most trainee biostatisticians go through, and so people have shoved various books into my hands to help me get up to speed. I'll omit the names of many of the books to protect the guilty, but the most useful book someone pressed innto my hands was The Little SAS Book, which I read cover to cover in two sittings.



The Little SAS Book is more technical than the others, hence more suitable for programmers, and actually gives you an inkling of what the designers of the language were thinking. That's helped me begin to think in the language, which is something none of the other books have helped me to do.



The best comparison I can come up with for now is that SAS is like German, whereas R is like Japanese. SAS has lots of compound statements, each of which does a lot, while R has many small statements which each do a little bit. So would you like to be able to speak German or Japanese? The correct answer is, of course, both, each at the appropriate time :)

Mark Greenaway: Gainfully employed

Mon, 2014-08-25 01:26
A while ago, I applied for a job as a biostatistician in public health. I made it to the interview stage, and that seemed to go quite well. They said they'd contact me in seven to ten days. I didn't hear anything for a while, but eventually I bumped into one of my referees who said he'd spoken with my interviewers, and they sounded "very positive". I poked my other referee, and he said they'd spoken to him too. So that was sounding pretty good.



On the advice of my girlfriend, I asked them how things were going, and they said they were waiting for a criminal record check to complete. Owing to my misspent youth, there's no criminal record to check, so now I was feeling very positive indeed. To cut a long story short, today they offered me a position, and I accepted.



So all's well that ends well!

Mark Greenaway: British Medical Journal publishes paper on the risks of head banging

Mon, 2014-08-25 01:26
Head and neck injury risks in heavy metal



This is the funniest thing I've seen in ages. I particularly like the mitigation options: many injuries could be prevented if AC/DC would stop playing Back In Black live, and instead play Moon River ;)

Mark Greenaway

Mon, 2014-08-25 01:26
Sometimes I feel like I'm not so much in control of my body as sending it memoes. And it responds with things like "Tough job, hip rotation. Can you come back Monday?".

Mark Greenaway: True Temperament

Mon, 2014-08-25 01:26
I've been playing a few more jazz chords and moveable chord forms of late, and my ear's been getting a little better. Unfortunately, this means I've become more sensitive to how out of tune the notes in some of those chords sound as you move up the neck.



To some extent, this problem is inherent in the guitar's construction. There are some very determined people at a company called True Temperament who've decided to do something about this by making custom necks with strange looking curved frets. The FAQ on that site also goes into some depth about tuning methods and why the problem is unsolvable on a standard guitar.



So I'm going to have to live with it, or pick up a saxophone or something :)

Mark Greenaway: Judo

Mon, 2014-08-25 01:26
Judo is going well. I've been working on the fundamentals a lot recently, especially breakfalling. I'm finally getting to the point where I'm losing my fear of being thrown - the people in my club are nice and aren't there to hurt people, and I've learnt that by just going with the throw rather than resisting you can breakfall more cleanly. That way, you're very unlikely to get hurt. And if you pay attention while you're being thrown, you tend to learn more about how the throw works, so when it comes your turn, you'll do it better.



Being a lightweight, I've got to fight differently to the heavier judoka, so in the next little while I'm going to focus on improving my speed and perfecting my technique for the basic throws and sweeps. If you're stronger you can just apply more force to get bad throwing techniques to work, but this isn't an option for me. I think ultimately it's a good thing, because I'll have to learn the throws properly.



Always more things to work on. Practice, practice, practice.