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OpenSTEM: Oceanography and the Continents

Wed, 2017-03-08 10:04

Marie Tharp (30 July, 1920 – 23 August, 2006) was an oceanographer and cartographer who mapped the oceans of the world. She worked with Bruce Heezen, who collected data on a ship, mapping the ocean floor.

Tharp and Heezen

Tharp turned the data into detailed maps. At that time women were not allowed to work on research ships, as it was thought that they would bring bad luck! However, Tharp was a skilled cartographer, and as she made her maps of the floor of the oceans of the world, with their ridges and valleys, she realised that there were deep valleys which showed the boundaries of continental plates. She noticed that these valleys were also places with lots of earthquakes and she became convinced of the basics of plate tectonics and continental drift.

Between 1959 and 1963, Tharp was not mentioned in any of the scientific papers published by Heezen, and he dismissed her theories disparagingly as “girl talk”. As this video  from National Geographic shows, she stuck to her guns and was vindicated by the evidence, eventually managing to persuade Heezen, and the scientific community at large, of the validity of the theories. In 1977, Heezen and Tharp published a map of the entire ocean floor. Tharp obtained degrees in English, Music, Geology and Mathematics during the course of her life. In 2001, a few weeks before her 81st birthday, Marie Tharp was awarded the Lamont-Doherty Heritage Award at Columbia University, in the USA, as a pioneer of oceanography. She died of cancer in 2006.

The National Geographic video provides an excellent testimony to this woman pioneer in oceanography.

Lev Lafayette: Multicore World 2017: A Review

Tue, 2017-03-07 16:05

Multicore World is a small conference held annually in New Zealand hosted by Open Parallel. What it lacks in numbers however it makes up in quality of the presenters. The 2017 conference included a typically impressive array of speakers dealing with some of the most difficult issues facing computational science, and included several important announcements in the fields of supercomputing, the Internet of Things, and manufacting issues.

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Craige McWhirter: Adventures in Unemployment

Mon, 2017-03-06 13:15

Due to a recent corporate fire sale, implosion, what ever you'd like to call it, I found myself joining thousands of my former colleagues unemployed and looking for "new opportunities" (hire me, I'm dead set amazing).

As a parent who also has an ex-wife and children it is incumbent upon me to inform the Department of Human Services (DHS) of any changes to my income within strict time frames. So like a dutiful slave of the state, I called them to advise of my new $0 income status.

The following conversation actually happened:

[DHS] "So taking into account your new income of $0, you will need to pay $114 / month."

[McW] "With an income of $0, how would you expect me to pay that?"

[DHS] "Borrow money from family and friends."

[McW] "You know you just said that out loud, right?"

[DHS] "Yes sir."

[McW] "Okay, so let me clarify this. I have an income of $0, 3 dependent children living with me, one dependent adult and the DHS priority is not for me to provide food and shelter for them but to pay child support?"

[DHS] "That is correct."

[McW] "..and this is something you've not only said out loud but on a phone call that's being recorded for 'service quality and training purposes'."

[DHS] "That is the nature of the legislation and what we are trained to say."

[McW] "You do see the problem here, don't you?"

[DHS] "Yes sir, I do."

[McW] "Are there any other things you're trained to say that might help?"

[DHS] "You could apply for work benefits."

[McW] "Okay, let's think this one through. Let's say I did get the dole, which would be about $400 / fortnight, less than my fortnightly rent even before I commence buying food, would the DHS still want $114 from that?

[DHS] "Yes, child support would be taken from the benefits before they were paid to you."

[McW] [long pause] "Back to the $0 income and obvious incapacity to pay, when the inevitable non-payment occurs, what does the DHS do next?"

[DHS] "Despite your excellent payment history, the DHS would have to pursue avenues for collection."

[McW] "So I have a family of 6 to shelter and support and the DHS will still end up going collect to strip us of whatever they can? That's not particularly helpful to anyone, not those I'm directly supporting nor my children for whom the DHS is collecting child support."

[DHS] "That's correct sir, once a child support debt of $1,000 is accrued, DHS will pursue collection avenues. Is there anything else I can help you with?"

[McW] "Unless you can change the legislation, I think we're good here. Thank you."

Having been in the child support "game" for about 13 years, having seen female friends dudded by former male partners, have seen male friends rorted by former female partners, it's not as though I was unaware the system was truly broken and unfair to all parties in so many cases.

This conversation however, was truly breathtaking. I doubt Douglas Adams could have scripted this any better. :-)

OpenSTEM: The Week in HASS – term 1, week 6

Mon, 2017-03-06 10:04

HASS students have a global focus this week. The younger students are looking at calendars, celebrations and which countries classmates are connected to, around the world. Older students are starting to explore what happened at the end of the Ice Age and the beginnings of agriculture and trade. These students will also be applying the scientific method to practical examinations – creating their own mini Ice Ages in a bowl and making mud bricks.

Foundation to Year 3

Our standalone Foundation/Prep classes (F.1) are looking at calendars and celebrations this week, starting to explore the world beyond their own family and gain an identity relative to each other. Integrated Foundation/Prep (F.5) and Year 1 (1.1) classes; as well as Year 1 (1.1), 2 (2.1) and 3 (3.1) classes are examining our OpenSTEM blackline world map and putting coloured dots on all the countries that they and their families are connected to, either through relatives, or by having lived there themselves. It is through this sort of exercise that students can start to understand the concept of the “global family”.

Year 3 to Year 6 Making an Ice Age

Students in years 3 (3.5), 4 (4.1), 5 (5.1) and 6 (6.1) are consolidating their learning and expanding into subjects, such as Science and Economics and Business. The ever-popular Ice Ages and Mud Bricks activity links to core Science curricular strands and allows students to explore their learning in very tactile ways. Whilst undertaking the activity, students make a mini Ice Age in a bowl, attempting to predict what will happen to their clay landscape when it is flooded and frozen, and then comparing these predictions to their recorded observations, during empirical testing. Students also make their own mud bricks by hand, once again predicting how to make the bricks strongest and testing different construction techniques. We have even had classes test the strength of their mud brick walls under simulated flood conditions, working inside a tidy tray.

Making mud bricks

Students move on from studying the Ice Age, looking at what happened as the climate changed and global sea levels rose. The pressures that these changes brought to people’s lives is examined by looking at the origins of agriculture with domestic plants and animals. Students consider how people needed to wok together to survive. The cooperative Trade and Barter activity allows students to role play life in a Neolithic village. Faced with a range of challenges, such as floods and droughts, students discover how to prioritise their needs for food to survive the winter, against their wants. They also discover that trade, counting and writing all grew out of the needs for people to exchange items and help each other to survive. This activity covers all the basic concepts in the Economics and Business curriculum, whilst providing a context that is meaningful to the students and their own experiences. Replicating the way that people developed trade, counting and writing in the historic period, the students’ experiences during the Trade and Barter activity lay the foundations for a deeper understanding of the basic concepts of Economics and Business.

flooding the mud brick wall

Ben Martin: Non self replicating reprap 3d printer

Sun, 2017-03-05 18:21
The reprap is designed to be able to "self replicate" to a degree. If a part on a reprap 3d printer breaks then a replacement part can be printed and attached. Parts can evolve as new ideas come along. Having parts crack or weaken on a 3d printer can be undesirable though.

A part on this printer was a mix of acrylic and PLA, both of which were cracked. Not quite what one would hope for as a foot of the y-axis. It is an interesting design with the two driving rods the same length as the alloy channel at the back of the printer.



A design I thought of called for 1/2 inch alloy in order to wrap the existing alloy extrusion with a 3mm cover. The dog bone on the slot is manually added in Fusion 360 so it is larger than needed. The whole thing being a learning exercise for me as to how to create 2.5D parts. The belt tensioning is on a 6mm subassembly that is mounted on the bracket in the right of the image below.


The bracket and subassembly are shown mounted below. Yes, using four M6 bolts to tension a belt is overkill. I would imagine you can stretch the belt to breaking point quite easily with these bolts. The two rods are locked into place using M3 tapped grub screws. The end brackets are bolted to the back extrusion using two M6 bolts.


The z-axis is now supported by a second 10mm alloy custom bracket. This combination makes it much, much harder to wobble the z-axis than the original design using plastic parts.