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OpenSTEM: This Week in HASS – term 1, week 4

Thu, 2017-02-23 15:05

This week the Understanding Our World program for primary schools has younger students looking at time passing, both in their own lives and as marked by others, including the seasons recognised by different Aboriginal groups. Older students are looking at how Aboriginal people interacted with the Australian environment, as it changed at the end of the Ice Age, and how they learnt to manage the environment and codified that knowledge into their lore.

Foundation to Year 3

This week our standalone Foundation classes  (Unit F.1) are thinking about what they were like as babies. They are comparing photographs or drawings of themselves as babies, with how they are now. This is a great week to involve family members and carers into class discussions, if appropriate. Students in multi-age classes and Years 1 to 3 (Units F.5, 1.1, 2.1 and 3.1) , are examining how weather and seasons change throughout the year and comparing our system of seasons with those used by different groups of Aboriginal people in different parts of Australia. Students can compare these seasons to the weather where they live and think about how they would divide the year into seasons that work where they live. Students can also discuss changes in weather over time with older members of the community.

Years 3 to 6

Older students, having followed the ancestors of Aboriginal people all the way to Australia, are now examining how the climate changed in Australia after the Ice Age, and how this affected Aboriginal people. They learn how Aboriginal people adapted to their changing environment and learned to manage it in a sustainable way. This vitally important knowledge about how to live with, and manage, the Australian environment, was codified into Aboriginal lore and custom and handed down in stories and laws, from generation to generation. Students start to examine the idea of Country/Place, in this context.

Julien Goodwin: Making a USB powered soldering iron that doesn't suck

Wed, 2017-02-22 23:03
Today's evil project was inspired by a suggestion after my talk on USB-C & USB-PD at this years's linux.conf.au Open Hardware miniconf.

Using a knock-off Hakko driver and handpiece I've created what may be the first USB powered soldering iron that doesn't suck (ok, it's not a great iron, but at least it has sufficient power to be usable).

Building this was actually trivial, I just wired the 20v output of one of my USB-C ThinkPad boards to a generic Hakko driver board, the loss of power from using 20v not 24v is noticeable, but for small work this would be fine (I solder in either the work lab or my home lab, where both have very nice soldering stations so I don't actually expect to ever use this).

If you were to turn this into a real product you could in fact do much better, by doing both power negotiation and temperature control in a single micro, the driver could instead be switched to a boost converter instead of just a FET, and by controlling the output voltage control the power draw, and simply disable the regulator to turn off the heater. By chance, the heater resistance of the Hakko 907 clone handpieces is such that combined with USB-PD power rules you'd always be boost converting, never needing to reduce voltage.

With such a driver you could run this from anything starting with a 5v USB-C phone charger or battery (15W for the nicer ones), 9v at up to 3A off some laptops (for ~25W), or all the way to 20V@5A for those who need an extremely high-power iron. 60W, which happens to be the standard power level of many good irons (such as the Hakko FX-888D) is also at 20v@3A a common limit for chargers (and also many cables, only fixed cables, or those specially marked with an ID chip can go all the way to 5A). As higher power USB-C batteries start becoming available for laptops this becomes a real option for on-the-go use.

Here's a photo of it running from a Chromebook Pixel charger:

Linux Australia News: $AUD 35k available in 2017 Grants Program

Tue, 2017-02-21 11:00

Linux Australia is delighted to announce the availability of $AUD 35,000
for open source, open data, open government, open education, open
hardware and open culture projects, as part of the organisation’s
commitment to free and open source systems and communities in the region.

This year, we have deliberately weighted some areas in which we strongly
welcome grant applications.

More information is available at: https://linux.org.au/projects/grants

Please do share this with colleagues who may find it of interest, and
feel free to contact the Linux Australia Council if you would like a
private discussion.

With kind regards,

Kathy Reid

President, Linux Australia

Binh Nguyen: Life in India, Prophets/Pre-Cogs/Stargate Program 7, and More

Tue, 2017-02-21 01:56
On India: - your life is very much dependent on how you were born, how much you money you have, etc... In spite of being a capitalist, democracy it still bears aspects of being stuck with a caste/feudal/colonial system. Electrical power stability issues still. Ovens generally lacking. Pollution and traffic problems no matter where you live in India. They have the same number of hours in each

Sridhar Dhanapalan: New LinkedIn Interface Delete Your Data? Here’s How to Bring it Back.

Mon, 2017-02-20 13:02

Over the past few years it has seemed like LinkedIn were positioning themselves to take over your professional address book. Through offering CRM-like features, users were able to see a summary of their recent communications with each connection as well as being able to add their own notes and categorise their connections with tags. It appeared to be a reasonable strategy for the company, and many users took the opportunity to store valuable business information straight onto their connections.

Then at the start of 2017 LinkedIn decided to progressively foist a new user experience upon its users, and features like these disappeared overnight in lieu of a more ‘modern’ interface. People who grew to depend on this integration were in for a rude shock — all of a sudden it was missing. Did LinkedIn delete the information? There was no prior warning given and I still haven’t seen any acknowledgement or explanation (leave alone an apology) from LinkedIn/Microsoft on the inconvenience/damage caused.

If anything, this reveals the risks in entrusting your career/business to a proprietary cloud service. Particularly with free/freemium (as in cost) services, the vendor is more likely to change things on a whim or move that functionality to a paid tier.

It’s another reason why I’ve long been an advocate for open standards and free and open source software.

Fortunately there’s a way to export all of your data from LinkedIn. This is what we’ll use to get back your tags and notes. These instructions are relevant for the new interface. Go to your account settings and in the first section (“Basics”) you should see an option called “Getting an archive of your data”.

LinkedIn: Getting an archive of your data

Click on Request Archive and you’ll receive an e-mail when it’s available for download. Extract the resulting zip file and look for a file called Contacts.csv. You can open it in a text editor, or better yet a spreadsheet like LibreOffice Calc or Excel.

In my copy, my notes and tags were in columns D and E respectively. If you have many, it may be a lot of work to manually integrate them back into your address book. I’d love suggestions on how to automate this. Since I use Gmail, I’m currently looking into Google’s address book import/export format, which is CSV based.

As long as Microsoft/LinkedIn provide a full export feature, this is a good way to maintain ownership of your data. It’s good practice to take an export every now and then to give yourself some peace-of-mind and avoid vendor lock-in.

This article has also been published on LinkedIn.

Lev Lafayette: HPC/Cloud Hybrids for Efficient Resource Allocation and Throughput

Mon, 2017-02-20 07:03

HPC systems running massively parallel jobs need a fairly static software operating environment running on bare metal hardware, a high speed interconnect to reach their full potential, and offer linear performance scaling for cleverly designed applications. Cloud computing, on the other hand, offers flexible virtual environments and can be used for pleasingly parallel workloads.

read more

Sridhar Dhanapalan: CareerNexus: a new way to find work

Sun, 2017-02-19 19:02

The start-up that I have co-founded, CareerNexus, is looking for job seekers to take part in a product test and market experiment. If you, or someone you know, wants to know more and potentially take part, message me.

If we can help just a fraction of those people who have difficulty finding work through traditional means — people returning from parental leave, people looking for roles after being made redundant, mature workers, even some highly skilled professionals — we’ll be doing something great.

As an alternate means of finding work, it need not replace any mechanisms that you may already be engaged in. In other words, there is nothing for you to lose and hopefully much for you to gain.

Sridhar Dhanapalan: Published in Engineers Without Borders Magazine

Sun, 2017-02-19 19:02

Engineers Without Borders asked me to write something for their Humanitarian Engineering magazine about One Laptop per Child. Here is what I wrote.

The school bell rings, and the children filter into the classroom. Each is holding an XO – their own personal learning device.

Students from Doomadgee often use their XOs for outdoors education. The sunlight-readable screen
combined with the built-in camera allow for hands-on exploration of their environment.

This is no ordinary classroom. As if by magic, the green and white XOs automatically see each other as soon as they are started up, allowing children to easily share information and collaborate on activities together. The kids converse on how they can achieve the tasks at hand. One girl is writing a story on her XO, and simultaneously on the same screen she can see the same story being changed by a boy across the room. Another group of children are competing in a game that involves maths questions.

Children in Kiwirrkurra, WA, collaborate on an activity with help from teachers.

Through the XO, the learning in this classroom has taken on a peer-to-peer character. By making learning more fun and engaging, children are better equipped to discover and pursue their interests. Through collaboration and connectivity, they can exchange knowledge with their peers and with the world. In the 21st century, textbooks should be digital and interactive. They should be up-to-date and locally relevant. They should be accessible and portable.

Of course, the teacher’s role remains vital, and her role has evolved into that of a facilitator in this knowledge network. She is better placed to provide more individual pathways for learning. Indeed the teacher is a learner as well, as the children quickly adapt to the new technology and learn skills that they can teach back.

A teacher in Jigalong, WA, guides a workgroup of children in their class.

Helping to keep the classroom session smoothly humming along are children who have proven themselves to be proficient with assisting their classmates and fixing problems (including repairing hardware). These kids have taken part in training programmes that award them for their skills around the XO. In the process, they are learning important life skills around problem solving and teamwork.

Dozens of students in Doomadgee State School are proficient in fixing XO hardware.

This is all part of the One Education experience, an initiative from One Laptop per Child (OLPC) Australia. This educational programme provides a holistic educational scaffolding around the XO, the laptop developed by the One Laptop per Child Association that has its roots in the internationally-acclaimed MIT Media Lab in the USA.

The XO was born from a desire to empower each and every child in the world with their own personal learning device. Purpose-built for young children and using solid open source software, the XO provides an ideal platform for classroom learning. Designed for outdoors, with a rugged design and a high-resolution sunlight-readable screen, education is no longer confined to a classroom or even to the school grounds. Learning time needn’t stop with the school bell – many children are taking their XOs home. Also important is the affordability and full repairability of the devices, making it cost-effective versus non-durable and ephemeral items such as stationery, textbooks and other printed materials. There are over 3 million XOs in distribution, and in some countries (such as Uruguay) every child owns one.

A One Education classroom in Kenya.

One Education’s mission is to provide educational opportunities to every child, no matter how remote or disadvantaged. The digital divide is a learning divide. This can be conquered through a combination of modern technology, training and support, provided in a manner that empowers local schools and communities. The story told above is already happening in many classrooms around the country and the world.

A One Education classroom in northern Thailand.

With teacher training often being the Achilles’ heel of technology programmes in the field of education, One Education focuses only on teachers who have proven their interest and aptitude through the completion of a training course. Only then are they eligible to receive XOs (with an allocation of spare parts) into their classroom. Certified teachers are eligible for ongoing support from OLPC Australia, and can acquire more hardware and parts as required.

As a not-for-profit, OLPC Australia works with sponsors to heavily subsidise the costs of the One Education programme for low socio-economic status schools. In this manner, the already impressive total cost of ownership can be brought down even further.

High levels of teacher turnover are commonplace in remote Australian schools. By providing courses online, training can be scalable and cost-effective. Local teachers can even undergo further training to gain official trainer status themselves. Some schools have turned this into a business – sending their teacher-trainers out to train teachers in other schools.

Students in Geeveston in Tasmania celebrate their attainment of XO-champion status, recognising
their proficiency in using the XO and their helpfulness in the classroom.

With backing from the United Nations Development Programme, OLPC are tackling the Millennium Development Goals by focusing on Goal 2 (Achieve Universal Primary Education). The intertwined nature of the goals means that progress made towards this goal in turn assists the others. For example, education on health can lead to better hygiene and lower infant mortality. A better educated population is better empowered to help themselves, rather than being dependent on hand-outs. For people who cannot attend a classroom (perhaps because of remoteness, ethnicity or gender), the XO provides an alternative. OLPC’s focus on young children means that children are becoming engaged in their most formative years. The XO has been built with a minimal environmental footprint, and can be run off-grid using alternate power sources such as solar panels.

One Education is a young initiative, formed based on experiences learnt from technology deployments in Australia and other countries. Nevertheless, results in some schools have been staggering. Within one year of XOs arriving in Doomadgee State School in northern Queensland, the percentage of Year 3 pupils meeting national literacy standards leapt from 31% to 95%.

A girl at Doomadgee State School very carefully removes the screen from an XO.

2013 will see a rapid expansion of the programme. With $11.7m in federal government funding, 50,000 XOs will be distributed as part of One Education. These schools will be receiving the new XO Duo (AKA XO-4 Touch), a new XO model developed jointly with the OLPC Association. This version adds a touch-screen user experience while maintaining the successful laptop form factor. The screen can swivel and fold backwards over the keyboard, converting the laptop into a tablet. This design was chosen in response to feedback from educators that a hardware keyboard is preferred to a touch-screen for entering large amounts of information. As before, the screen is fully sunlight-readable. Performance and battery life have improved significantly, and it is fully repairable as before.

As One Education expands, there are growing demands on OLPC Australia to improve the offering. Being a holistic project, there are plenty of ways in which we could use help, including in education, technology and logistics. We welcome you to join us in our quest to provide educational opportunities to the world’s children.

Pia Waugh: Choose your own adventure – keynote

Sun, 2017-02-19 07:01

This is a blog version of the keynote I gave at linux.conf.au 2017. Many thanks to everyone who gave such warm feedback, and I hope it helps spur people to think about systemic change and building the future. The speech can be watched at https://www.youtube.com/watch?v=J6IqGuxCKa8.

I genuinely believe we are at a tipping point right now. A very important tipping point where we have at our disposal all the philosophical and technical means to invent whatever world we want, but we’re at risk of reinventing the past with shiny new things. This talk is about trying to make active choices about how we want to live in future and what tools we keep or discard to get there. Passive choices are still a choice, they are choosing the status quo. We spend a lot of our time tinkering around the edges of life as it is, providing symptomatic relief for problems we find, but we need to take a broader systems based view and understand what systemic change we can make to properly address those problems.

We evolved over hundreds of thousands of years using a cooperative competitive social structure that helped us work together to flourish in every habitat, rapidly and increasingly evolve an learn, and establish culture, language, trade and travel. We were constantly building on what came before and we built our tools as we went.

In recent millennia we invented systems of complex differentiated and interdependent skills, leading to increasingly rapid advancements in how we live and organise ourselves physically, politically, economically and socially, especially as we started building huge cities. Lots of people meant a lot of time to specialise, and with more of our basic needs taken care of, we had more time for philosophy and dreaming.

Great progress created great surplus, creating great power, which we generally centralised in our great cities under rulers that weren’t always so great. Of course, great power also created great inequalities so sometimes we burned down those great cities, just to level the playing field. We often took a symptomatic relief approach to bad leaders by replacing them, without fundamentally changing the system.

But in recent centuries we developed the novel idea that all people have inalienable rights and can be individually powerful. This paved the way for a massive culture shift and distribution of power combined with heightened expectations of individuals in playing a role in their own destiny, leading us to the world as we know it today. Inalienable rights paved the way for people thinking differently about their place in the world, the control they had over their lives and how much control they were happy to cede to others. This makes us, individually, the most powerful we have ever beed, which changes the game moving forward.

You see, the internet was both a product and an amplifier of this philosophical transition, and of course it lies at the heart of our community. Technology has, in large part, only sped up the cooperative competitive models of adapting, evolving and flourishing we have always had. But the idea that anyone has a right to life and liberty started a decentralisation of power and introduced the need for legitimate governance based on the consent of citizens (thank you Locke).

Citizens have the powers of publishing, communications, monitoring, property, even enforcement. So in recent decades we have shifted fundamentally from kings in castles to nodes in a network, from scarcity to surplus or reuse models, from closed to open systems, and the rate of human progress only continues to grow towards an asymptoic climb we can’t even imagine.

To help capture this, I thought I’d make a handy change.log on human progress to date.

# Notable changes to homo sapiens – change.log
## [2.1.0] – 1990s CE “technology revolution & internet”
### Changed
– New comms protocol to distribute “rights”. Printing press patch unexpectedly useful for distributing resources. Moved from basic multi-core to clusters of independent processors with exponential growth in power distribution.

## [2.0.0] – 1789 CE “independence movements”
### Added
– Implemented new user permissions called “rights”, early prototype of multi-core processing with distributed power & comms.

## [1.2.0] – 1760 CE “industrial revolution”
### Changed
– Agricultural libraries replaced by industrial libraries, still single core but heaps faster.

## [1.1.1] – 1440 CE “gutenberg”
### Patched
– Printing press a minor patch for more efficient instructions distribution, wonder if it’d be more broadly useful?

## [1.1.0] – 2,000 BCE “cities era”
### Changed
– Switched rural for urban operating environment. Access to more resources but still on single core.

## [1.0.0] – 8,000 BCE “agricultural revolution”
### Added
– New agricultural libraries, likely will create surplus and population explosion. Heaps less resource intensive.

## [0.1.0] – 250,000 BCE “homo sapiens”
### Added
– Created fork from homo erectus, wasn’t confident in project direction though they may still submit contributions…

(For more information about human evolution, see https://www.bighistoryproject.com)

The point to this rapid and highly oversimplified historical introduction is threefold: 1) we are more powerful than ever before, 2) the rate of change is only increasing, and 3) we made all this up, and we can make it up again. It is important to recognise that we made all of this up. Intellectually we all understand this but it matters because we often assume things are how they are, and then limit ourselves to working within the constraints of the status quo. But what we invented, we can change, if we choose.

We can choose our own adventure, or we let others choose on our behalf. And if we unthinkingly implement the thinking, assumptions and outdated paradigms of the past, then we are choosing to reimplement the past.

Although we are more individually and collectively powerful than ever before, how often do you hear “but that’s just how we’ve always done it”, “but that’s not traditional”, or “change is too hard”. We are demonstrably and historically utter masters at change, but life has become so big, so fast, and so interrelated that change has become scary for many people, so you see them satisfied by either ignoring change or making iterative improvements to the status quo. But we can do better. We must do better.

I believe we are at a significant tipping point in history. The world and the very foundations our society were built on have changed, but we are still largely stuck in the past in how we think and plan for the future. If we don’t make some active decisions about how we live, think and act, then we will find ourselves subconsciously reinforcing the status quo at every turn and not in a position to genuinely create a better future for all.

So what could we do?

  • Solve poverty and hunger: distributed property through nanotechnology and 3D printing, universal education and income.
  • Work 2 days a week, automate the rest: work, see “Why the Future is Workless” by Tim Dunlop
  • Embrace and extend our selves: Transhumanism, para olympics, “He was more than a dolphin, but from another dolphin’s point of view he might have seemed like something less.” — William Gibson, from Johnny Mnemonic. Why are we so conservative about what it means to be human? About our picture of self? Why do we get caught up on what is “natural” when almost nothing we do is natural.
  • Overcome the tyranny of distance: rockets for international travel, interstellar travel, the opportunity to have new systems of organising ourselves
  • Global citizens: Build a mighty global nation where everyone can flourish and have their rights represented beyond the narrow geopolitical nature of states: peer to peer economy, international rights, transparent gov, digital democracy, overcome state boundaries,
  • ?? What else ?? I’m just scratching the surface!

So how can we build a better world? Luckily, the human species has geeks. Geeks, all of us, are special because we are the pioneers of the modern age and we get to build the operating system for all our fellow humans. So it is our job to ensure what we do makes the world a better place.

rOml is going to talk more about future options for open source in the Friday keynote, but I want to explore how we can individually and collectively build for the future, not for the past.

I would suggest, given our role as creators, it is incumbent on us to both ensure we build a great future world that supports all the freedoms we believe in. It means we need to be individually aware of our unconscious bias, what beliefs and assumptions we hold, who benefits from our work, whether diversity is reflected in our life and work, what impact we have on society, what we care about and the future we wish to see.

Collectively we need to be more aware of whether we are contributing to future or past models, whether belief systems are helping or hindering progress, how we treat others and what from the past we want to keep versus what we want to get rid of.

Right now we have a lot going on. On the one hand, we have a lot of opportunities to improve things and the tools and knowledge at our disposal to do so. On the other hand we have locked up so much of our knowledge and tools, traditional institutions are struggling to maintain their authority and control, citizens are understandably frustrated and increasingly taking matters into their own hands, we have greater inequality than ever before, an obsession with work at the cost of living, and we are expected to sacrifice our humanity at the alter of economics

Questions to ask yourself:

Who are/aren’t you building for?
What is the default position in society?
What does being human mean to you?
What do we value in society?
What assumptions and unconscious bias do you have?
How are you helping non-geeks help themselves?
What future do you want to see?

What should be the rights, responsibilities and roles of
citizens, governments, companies, academia?

Finally,we must also help our fellow humans shift from being consumers to creators. We are all only as free as the tools we use, and though geeks will always be able to route around damage, be that technical or social, many of our fellow humans do not have the same freedoms we do.

Fundamental paradigm shifts we need to consider in building the future.

Scarcity → Surplus
Closed → Open
Centralised → Distributed
Belief → Rationalism
Win/lose → Cooperative competitive
Nationalism → Transnationalism
Normative humans → Formative humans

Open source is the best possible modern expression of cooperative competitiveness that also integrates our philosophical shift towards human rights and powerful citizens, so I know it will continue to thrive and win when pitted against closed models, broadly speaking.

But in inventing the future, we need to be so very careful that we don’t simply rebuild the past with new shiny tools. We need to keep one eye always on the future we want to build, on how what we are doing contributes to that future, and to ensuring we have enough self awareness and commitment to ensuring we don’t accidentally embed in our efforts the outdated and oftentimes repressive habits of the past.

To paraphrase Gandhi, build the change you want to see. And build it today.

Thank you, and I hope you will join me in forging a better future.

Binh Nguyen: Life in Sudan (technically North and South Sudan), Life in Somalia, and More

Sat, 2017-02-18 22:43
- Kingdom of Kush was one of first recorded instances of Sudan in history. Strong influence of ancient Egyptian empire and their Gods. Strong religious influence with Christianity and then Islam thereafter. Has struggled with internal conflict for a long time  sudan history https://www.youtube.com/results?search_query=sudan+history https://en.wikipedia.org/wiki/Foreign_relations_of_Sudan -

OpenSTEM: New Research on Our Little Cousins to the North!

Thu, 2017-02-16 19:05
Homo floresiensis

Last year, several research papers were published on the ongoing excavations and analysis of material from the island of Flores in Indonesia, where evidence of very small stature hominins was found in the cave of Liang Bua, in 2003. The initial dates dated these little people to between 50,000 and about 14,000 years ago, which would have meant that they lived side-by-side with anatomically modern humans in Indonesia, in the late Ice Age. The hominins, dubbed Homo floresiensis, after the island on which they were found, stood about 1m tall – smaller than any group of modern humans known. Their tiny size included a tiny brain – more in the range of 4 million year old Australopithecus than anything else. However, critical areas of higher order thinking in their brains were on par with modern humans.

Baffled by the seeming wealth of contradictions, these little people raised, researchers returned to the island, and the cave of Liang Bua, determined to check all of their findings in even more detail. Last year, they reported that they had in fact made some mistakes, the first time around. Very, very subtle changes in the sediments of the deposits, revealed that the Homo floresiensis bones belonged to some remnant older deposits, which had been eroded away in other parts of the cave, and replaced by much younger layers. Despite the samples for dating having been taken from close to the hominin bones, as luck would have it, they were all in the younger deposits! New dates, run on the actual sediments containing the bones, gave ages of between 190,000 to 60,000 years. Dates from close to the stone tools found with the hominins gave dates down to 50,000 years ago, but no later.

Liang Bua. Image by Rosino

The researchers – demonstrating a high level of ethics and absolutely correct scientific procedure, published the amended stratigraphy and dates, showing how the errors had occurred. At another site, Mata Menge, they had also found some ancestral hominins – very similar in body type to the ones from Liang Bua, dated to 700,000 years ago. Palaeoanthropologists were able to find similarities linking these hominins to the early Homo erectus found on Java and dated to about 1.2 million years ago, leading researchers to suggest that Homo floresiensis was a parallel evolution to modern humans, out of early Homo erectus in Indonesia, making them a fairly distant cousin on the grand family tree.

Careful examination of the deposits has now also called in to question whether Homo floresiensis could control fire. We know that they made stone tools – of a type pretty much unchanged over more than 600,000 years, and they used these tools to help them hunt Stegodon – an Ice Age dwarf elephant, which was as small as 1.5m at the shoulder. However, researchers now think that evidence of controlled fire is only in layers associated with modern humans. It is this cross-over between Homo floresiensis and modern humans, arriving about 60,000 – 50,000 years ago, that is a focus of current research – including that of teams working there now. At the moment, it looks as if Homo floresiensis disappears at about the same time that modern humans arrive, which sadly, is a not totally unlikely pattern.

Stegodon. Image by I, Vjdchauhan.

What does this have to do with Australia? Well, it’s always interesting to get information about our immediate neighbours and their history (and prehistory). But beyond that – we know that the ancestors of Aboriginal people (modern humans) were in Australia by about 60,000 – 50,000 years ago, so understanding how they arrived is part of understanding our own story. For more case studies on interesting topics in archaeology and palaeontology see our Archaeology Textbook resources for Year 11 students.

Craig Sanders: New D&D Cantrip

Thu, 2017-02-16 19:03

Name: Alternative Fact
Level: 0
School: EN
Time: 1 action
Range: global, contagious
Components: V, S, M (one racial, cultural or religious minority to blame)
Duration: Permanent (irrevocable)
Classes: Cleric, (Grand) Wizard, Con-man Politician

The caster can tell any lie, no matter how absurd or outrageous (in fact, the more outrageous the better), and anyone hearing it (or hearing about it later) with an INT of 10 or less will believe it instantly, with no saving throw. They will defend their new belief to the death – theirs or yours.

This belief can not be disbelieved, nor can it be defeated by any form of education, logic, evidence, or reason. It is completely incurable. Dispel Magic does not work against it, and Remove Curse is also ineffectual.

New D&D Cantrip is a post from: Errata

Chris Neugebauer: Two Weeks’ Notice

Thu, 2017-02-16 11:02

Last week, a rather heavy document envelope showed up in the mail.

Inside I found a heavy buff-coloured envelope, along with my passport — now containing a sticker featuring an impressive collection of words, numbers, and imagery of landmarks from the United States of America. I’m reliably informed that sticker is the valid US visa that I’ve spent the last few months applying for.

Having that visa issued has unblocked a fairly important step in my path to moving in with Josh (as well as eventually getting married, but that’s another story). I’m very very excited about making the move, though very sad to be leaving the city I’ve grown up in and come to love, for the time being.

Unrelatedly, I happened to have a trip planned to Montréal to attend ConFoo in March. Since I’ll already be in the area, I’m using that trip as my opportunity to move.

My last day in Hobart will be Thursday 2 March. Following that, I’ll be spending a day in Abu Dhabi (yes, there is a good reason for this), followed by a week in Montréal for ConFoo.

After that, I’ll be moving in with Josh in Petaluma, California on Saturday 11 March.

But until then, I definitely want to enjoy what remaining time I have in Hobart, and catch up with many many people.

Over the next two weeks I’ll be:

  • Attending, and presenting a talk at WD42 — my talk will be one of my pieces for ConFoo, and is entirely new material. Get along!
  • Having a farewell do, *probably* on Tuesday 28 February (but that’s not confirmed yet). I’ll post details about where and when that’ll be in the near future (once I’ve made plans)
  • Madly packing and making sure that that I use up as close to 100% of my luggage allowance as possible

If you want to find some time to catch up over the next couple of weeks, before I disappear for quite some time, do let me know.

David Rowe: FreeDV 700C

Thu, 2017-02-16 09:03

Over the past month the FreeDV 700C mode has been developed, integrated into the FreeDV GUI program version 1.2, and tested. Windows versions (64 and 32 bit) of this program can be downloaded from freedv.org. Thanks Richard Shaw for all your hard work on the release and installers.

FreeDV 700C uses the Codec 2 700C vocoder with the COHPSK modem. Some early results:

  • The US test team report 700C contacts over 2500km at SNRs down to -2dB, in conditions where SSB cannot be heard.
  • My own experience: the 700C speech quality is not quite as good as FreeDV 1600, but usable for conversation. That’s OK – it’s very early days for the 700C codec, and hey, it’s half the bit rate of 1600. I’m actually quite excited that 700C can be used conversationally at this early stage! I experienced a low SNR channel where FreeDV 700C didn’t work but SSB did, however 700C certainly works at much lower SNRs than 1600.
  • Some testers in Europe report 700C falling over at relatively high SNRs (e.g. 8dB). I also experienced this on a 1500km contact. Suspect this is a bug or corner case we can fix, especially in light of the US teams results.

Tony, K2MO, has put together this fine video demonstrating the various FreeDV modes over a simulated HF channel:

It’s early days for 700C, and there are mixed reports. However it’s looking promising. My next steps are to further explore the real world operation of FreeDV 700C, and work on improving the low SNR performance further.

Binh Nguyen: Life in Libya, Going off the Grid, and More

Wed, 2017-02-15 23:54
On Libya: - Berber tribes are indigenous people. For most of its history, Libya has been subjected to varying degrees of foreign control, from Europe, Asia, and Africa. The modern history of independent Libya began in 1951. The history of Libya comprises six distinct periods: Ancient Libya, the Roman era, the Islamic era, Ottoman rule, Italian rule, and the Modern era. Very small population of

David Rowe: Modems for HF Digital Voice Part 2

Wed, 2017-02-15 13:03

In the previous post I argued that pushing bits through a HF channel involves much wailing and gnashing of teeth. Now we shall apply numbers and graphs to the problem, which is – in a nutshell – Engineering.

QPSK Modem Simulation

I have worked up a GNU Octave modem simulation called hf_modem_curves.m. This operates at 1 sample/symbol, i.e. the sample rate is the symbol rate. So we takes some random bits, map them to QPSK symbols, add noise, then turn the noisy symbols back into bits and count errors:

The simulation ignores a few real world details like timing and phase synchronisation, so is a best case model. That’s OK for now. QPSK uses symbols that each carry 2 bits of information, here is the symbol set or “constellation”:

Four different points, each representing a different 2 bit combination. For example the bits ’00’ would be the cross at 45 degrees, ’10’ at 135 degrees etc. The plot above shows all possible symbols, but we just send one at a time. However it’s useful to plot all of the received symbols like this, as an indication of received signal quality. If the channel is playing nice, we receive something like this:

Each cross is now a fuzzy dot, as noise has been added by the channel. No bit errors yet – a bit error happens when we get enough noise to move received symbols into another quadrant. This sort of channel is called Additive White Gaussian Noise (AWGN). Line of site UHF radio is a good example of a real world AWGN channel – all you have to worry about is additive noise.

With a fading or multipath channel like HF we end up with something like:

In a fading channel the received symbol amplitudes bounce up and down as the channel fades in and out. Sometimes the symbols dip down into the noise and we get lots of bit errors. Sometimes the signal is reinforced, and the symbol amplitude gets bigger.

The simulation used for the multipath or HF channel uses a two path model, with additive noise as per the AWGN simulation:

Graphs and Modem Performance

Turns out there are some surprisingly good models to help us work out the expected Bit Error Rate (BER) for a modem. By “model” I mean people have worked out the maths to describe the Bit Error Rate (BER) for a QPSK Modem. This graph shows us how to work out the BER for QPSK (and BPSK):

So the red line shows us the BER given Eb/No (E-B on N-naught), which is a normalised form of Signal to Noise Ratio (SNR). Think about Eb/No as a modem running at 1 bit per second, with the noise power measured in 1 Hz of bandwidth. It’s a useful scale for comparing modems and modulation schemes.

Looking at the black lines, we can see that for an Eb/No or 4dB, we can expect a BER of 1E-2 or 0.01 or 1% of our bits will be received in error over an AWGN channel. This curve is for QPSK or BPSK, different curves would be used for other modems like FSK.

Given Eb/No you can work out the SNR if you know the bit rate and noise bandwidth:

SNR = S/N = EbRb/NoB

or in dB:

SNR(dB) = Eb/No(dB) + 10log10(Rb/B)

For example at Rb = 1600 bit/s and a noise bandwidth B = 3000 Hz:

SNR(dB) = 4 + 10log10(1600/3000) = 1.27 dB

OK, so that was for ideal QPSK. Lets add a few more curves to our graph:

We have added the experimental results for our QPSK simulation (green), and for Differential QPSK (DQPSK – blue). Our QPSK modem simulation (green) is right on top of the theoretical QPSK curve (red) – this is good and shows our simulation is working really well.

DQPSK was discussed in Part 1. Phase differences are sent, which helps with phase errors in the channels but costs us extra bit errors. This is evident on the curves – at the 1E-2 BER line, DQPSK requires 7dB Eb/No, 3dB more (double the power) of QPSK.

Now lets look at modem performance for HF (multipath) channels, on this rather busy graph (click for larger version):

Wow, HF sucks. Looking at the theoretical HF QPSK performance (straight red line) to achieve a BER of 1E-2, we need 14dB of Eb/No. That’s 10dB worse than QPSK on the AWGN channel. With DQPSK, we need about 16dB.

For HF, a lot of extra power is required to make a small difference in BER.

Some of the kinks in the HF curves (e.g. green QPSK HF simulated just under red QPSK HF theory) are due to not enough simulation points – it’s not actually possible to do better than theory!

Estimated Performance of FreeDV Modes

Now we have the tools to estimate the performance of FreeDV modes. FreeDV 1600 uses Codec 2 at 1300 bit/s, plus a little FEC at 300 bit/s to give a total of 1600 bit/s. With the FEC, lets say we can get reasonable voice quality at 4% BER. FreeDV 1600 uses a DQPSK modem.

On an AWGN channel, that’s an Eb/No of 4.4dB for DQPSK, and a SNR of:

SNR(dB) = 4.4 + 10log10(1600/3000) = 1.7 dB

On a multipath channel, that’s an Eb/No of 11dB for DQPSK, and a SNR of:

SNR(dB) = 11 + 10log10(1600/3000) = 8.3 dB

As discussed in Part 1, FreeDV 700C uses diversity and coherent QPSK, and has a multipath (HF) performance curve plotted in cyan above, and close to ideal QPSK on AWGN channels. The payload data rate is 700 bit/s, however we have an overhead of two pilot symbols for every 4 data symbols. This means we effectively need a bit rate of Rb = 700*(4+2)/4 = 1050 bit/s to pump 700 bits/s through the channel. It doesn’t have any FEC (yet, anyway), so we need a BER of a little lower than FreeDV 1600, about 2%. Running the numbers:

On an AWGN channel, for 2% BER we need an Eb/No of 3dB for QPSK, and a SNR of:

SNR(dB) = 3 + 10log10(1050/3000) = -1.5 dB

On a multipath channel, diversity (cyan line) helps a lot, that’s an Eb/No of 8dB, and a SNR of:

SNR(dB) = 8 + 10log10(1050/3000) = 3.4 dB

The diversity model in the simulation uses two carriers. The amplitudes of each carrier after passing through the multipath model are plotted below:

Often when one carrier is faded, the other is not faded, so when we recombine them at the receiver we get an average that is closer to AWGN performance. However diversity is not perfect, occasionally both carriers are wiped out at the same time by a fade.

So we can see FreeDV 700C is about 4 dB in front of FreeDV 1600, which matches the best reports from early adopters. I’ve had reports of FreeDV 700C operating at as low as -2dB , which is presumably on channels that don’t have heavy fading and are more like AWGN. Also some reports of 700C falling over at high SNRs (around like 8dB)! However that is probably a bug, e.g. a sync issue or something else we can track down in time.

Real world channels can vary. The multipath model above doesn’t take into account fast or slow fading, it just calculates the average bit errors rate. In practice, slow fading is hard to handle in digital voice applications, as the whole channel might be wiped out for a few seconds.

Now that we have a reasonable 700 bit/s codec – we can also consider other schemes, such as a more powerful FEC code rather than diversity. Like diversity, FEC codes provide “coding gain”, moving our operating point to the left. Really good codes operate at 10% BER, right over on the Eb/No = 2dB region of the curve. No free lunch of course – such codes may require long latency (seconds) or be expensive to decode.

Next Steps

I’d like to “instrument” FreeDV 700C and work with the 700C early adopters to find out how well it’s working, why and how it falls over, and work through any obvious bugs. Then start experimenting with ways to make it operate at lower SNRs, such as more powerful FEC codes or even non-redundant techniques like Trellis decoding.

Now we have shown Codec 700C has sufficient quality for conversations over the air, I’m planning another iteration of the Codec 2 700C vocoder design to see if we can improve speech quality.

Links

Modems for HF Digital Voice Part 1.

More Eb/No to SNR worked examples.

Similar modem calculations were used to develop a 100 kbit/s telemetry system to send HD images from High Altitude Balloons.

Stewart Smith: j-core + Numato Spartan 6 board + Fedora 25

Tue, 2017-02-14 19:00

A couple of changes to http://j-core.org/#download_bitstream made it easy for me to get going:

  • In order to make ModemManager not try to think it’s a “modem”, create /etc/udev/rules.d/52-numato.rules with the following content: # Make ModemManager ignore Numato FPGA board ATTRS{idVendor}=="2a19", ATTRS{idProduct}=="1002", ENV{ID_MM_DEVICE_IGNORE}="1"
  • You will need to install python3-pyserial and minicom
  • The minicom command line i used was: sudo stty -F /dev/ttyACM0 -crtscts && minicom -b 115200 -D /dev/ttyACM0

and along with the instructions on j-core.org, I got it to load a known good build.

OpenSTEM: This Week in HASS – term 1, week 3

Tue, 2017-02-14 15:04

This is a global week in HASS for primary students. Our youngest students are marking countries around the world where they have family members, slightly older students are examining the Mayan calendar, while older students get nearer to Australia, examining how people reached Australia and encountered its unique wildlife.

Foundation to Year 3 Mayan date

Foundation students doing the Me and My Global Family unit (F.1) are working with the world map this week, marking countries where they have family members with coloured sticky dots. Those doing the My Global Family unit (F.6), and students in Years 1 to 3 (Units 1.1; 2.1 and 3.1), are examining the Mayan calendar this week. The Mayan calendar is a good example of an alternative type of calendar, because it is made up of different parts, some of which do not track the seasons, and is cyclical, based on nested circles. The students learn about the 2 main calendars used by the Mayans – a secular and a celebratory sacred calendar, as well as how the Mayans divided time into circles running at different scales – from the day to the millennium and beyond. And no, in case anyone is still wondering – they did not predict the end of the world in 2012, merely the end of one particular long-range cycle, and hence, the beginning of a new one…

Years 3 to 6 Lake Mungo, where people lived at least 40,000 years ago.

Students doing the Exploring Climates unit (3.6), and those in Years 4 to 6 (Units 4.1, 5.1 and 6.1), are examining how people reached Australia during the Ice Age, and what Australia was like when they arrived. People had to cross at least 90km of open sea to reach Australia, even during the height of the Ice Age, and this sea gap led to the relative isolation of animals in Australia from others in Asia. This phenomenon was first recorded by Alfred Wallace, who drew a line on a map marking the change in fauna. This line became known as the Wallace line, as a result. Students will also examine the archaeological evidence, and sites of the first people in Australia, ancestors of Aboriginal people. The range of sites across Australia, with increasingly early dates, amply demonstrate the depth of antiquity of Aboriginal knowledge and experience in Australia.

Binh Nguyen: Life in Syria, Why the JSF isn't Worth It, and More

Mon, 2017-02-13 22:34
Given what has happened wanted to see what has been happening inside Syria: https://en.wikipedia.org/wiki/Syria http://www.aljazeera.com/topics/country/syria.html http://www.aljazeera.com/programmes/specialseries/2017/02/boy-started-syrian-war-170208093451538.html - complicated colonial history with both British and French. Has had limited conflict with some of it's neighbours including

sthbrx - a POWER technical blog: High Power Lustre

Mon, 2017-02-13 16:29

(Most of the hard work here was done by fellow blogger Rashmica - I just verified her instructions and wrote up this post.)

Lustre is a high-performance clustered file system. Traditionally the Lustre client and server have run on x86, but both the server and client will also work on Power. Here's how to get them running.

Server

Lustre normally requires a patched 'enterprise' kernel - normally an old RHEL, CentOS or SUSE kernel. We tested with a CentOS 7.3 kernel. We tried to follow the Intel instructions for building the kernel as much as possible - any deviations we had to make are listed below.

Setup quirks

We are told to edit ~/kernel/rpmbuild/SPEC/kernel.spec. This doesn't exist because the directory is SPECS not SPEC: you need to edit ~/kernel/rpmbuild/SPECS/kernel.spec.

I also found there was an extra quote mark in the supplied patch script after -lustre.patch. I removed that and ran this instead:

for patch in $(<"3.10-rhel7.series"); do \ patch_file="$HOME/lustre-release/lustre/kernel_patches/patches/${patch}" \ cat "${patch_file}" >> $HOME/lustre-kernel-x86_64-lustre.patch \ done

The fact that there is 'x86_64' in the patch name doesn't matter as you're about to copy it under a different name to a place where it will be included by the spec file.

Building for ppc64le

Building for ppc64le was reasonably straight-forward. I had one small issue:

[build@dja-centos-guest rpmbuild]$ rpmbuild -bp --target=`uname -m` ./SPECS/kernel.spec Building target platforms: ppc64le Building for target ppc64le error: Failed build dependencies: net-tools is needed by kernel-3.10.0-327.36.3.el7.ppc64le

Fixing this was as simple as a yum install net-tools.

This was sufficient to build the kernel RPMs. I installed them and booted to my patched kernel - so far so good!

Building the client packages: CentOS

I then tried to build and install the RPMs from lustre-release. This repository provides the sources required to build the client and utility binaries.

./configure and make succeeded, but when I went to install the packages with rpm, I found I was missing some dependencies:

error: Failed dependencies: ldiskfsprogs >= 1.42.7.wc1 is needed by kmod-lustre-osd-ldiskfs-2.9.52_60_g1d2fbad_dirty-1.el7.centos.ppc64le sg3_utils is needed by lustre-iokit-2.9.52_60_g1d2fbad_dirty-1.el7.centos.ppc64le attr is needed by lustre-tests-2.9.52_60_g1d2fbad_dirty-1.el7.centos.ppc64le lsof is needed by lustre-tests-2.9.52_60_g1d2fbad_dirty-1.el7.centos.ppc64le

I was able to install sg3_utils, attr and lsof, but I was still missing ldiskfsprogs.

It seems we need the lustre-patched version of e2fsprogs - I found a mailing list post to that effect.

So, following the instructions on the walkthrough, I grabbed the SRPM and installed the dependencies: yum install -y texinfo libblkid-devel libuuid-devel

I then tried rpmbuild -ba SPECS/e2fsprogs-RHEL-7.spec. This built but failed tests. Some failed because I ran out of disk space - they were using 10s of gigabytes. I found that there were some comments in the spec file about this with suggested tests to disable, so I did that. Even with that fix, I was still failing two tests:

  • f_pgsize_gt_blksize: Intel added this to their fork, and no equivalent exists in the master e2fsprogs branches. This relates to Intel specific assumptions about page sizes which don't hold on Power.
  • f_eofblocks: This may need fixing for large page sizes, see this bug.

I disabled the tests by adding the following two lines to the spec file, just before make %{?_smp_mflags} check.

rm -rf tests/f_pgsize_gt_blksize rm -rf tests/f_eofblocks

With those tests disabled I was able to build the packages successfully. I installed them with yum localinstall *1.42.13.wc5* (I needed that rather weird pattern to pick up important RPMs that didn't fit the e2fs* pattern - things like libcom_err and libss)

Following that I went back to the lustre-release build products and was able to successfully run yum localinstall *ppc64le.rpm!

Testing the server

After disabling SELinux and rebooting, I ran the test script:

sudo /usr/lib64/lustre/tests/llmount.sh

This spat out one scary warning:

mount.lustre FATAL: unhandled/unloaded fs type 0 'ext3'

The test did seem to succeed overall, and it would seem that is a known problem, so I pressed on undeterred.

I then attached a couple of virtual harddrives for the metadata and object store volumes, and having set them up, proceeded to try to mount my freshly minted lustre volume from some clients.

Testing with a ppc64le client

My first step was to test whether another ppc64le machine would work as a client.

I tried with an existing Ubuntu 16.04 VM that I use for much of my day to day development.

A quick google suggested that I could grab the lustre-release repository and run make debs to get Debian packages for my system.

I needed the following dependencies:

sudo apt install module-assistant debhelper dpatch libsnmp-dev quilt

With those the packages built successfully, and could be easily installed:

dpkg -i lustre-client-modules-4.4.0-57-generic_2.9.52-60-g1d2fbad-dirty-1_ppc64el.deblustre-utils_2.9.52-60-g1d2fbad-dirty-1_ppc64el.deb

I tried to connect to the server:

sudo mount -t lustre $SERVER_IP@tcp:/lustre /lustre/

Initially I wasn't able to connect to the server at all. I remembered that (unlike Ubuntu), CentOS comes with quite an aggressive firewall by default. I ran the following on the server:

systemctl stop firewalld

And voila! I was able to connect, mount the lustre volume, and successfully read and write to it. This is very much an over-the-top hack - I should have poked holes in the firewall to allow just the ports lustre needed. This is left as an exercise for the reader.

Testing with an x86_64 client

I then tried to run make debs on my Ubuntu 16.10 x86_64 laptop.

This did not go well - I got the following error:

liblustreapi.c: In function ‘llapi_get_poollist’: liblustreapi.c:1201:3: error: ‘readdir_r’ is deprecated [-Werror=deprecated-declarations]

This looks like one of the new errors introduced in recent GCC versions, and is a known bug. To work around it, I found the following stanza in a lustre/autoconf/lustre-core.m4, and removed the -Werror:

AS_IF([test $target_cpu == "i686" -o $target_cpu == "x86_64"], [CFLAGS="$CFLAGS -Wall -Werror"])

Even this wasn't enough: I got the following errors:

/home/dja/dev/lustre-release/debian/tmp/modules-deb/usr_src/modules/lustre/lustre/llite/dcache.c:387:22: error: initialization from incompatible pointer type [-Werror=incompatible-pointer-types] .d_compare = ll_dcompare, ^~~~~~~~~~~ /home/dja/dev/lustre-release/debian/tmp/modules-deb/usr_src/modules/lustre/lustre/llite/dcache.c:387:22: note: (near initialization for ‘ll_d_ops.d_compare’)

I figured this was probably because Ubuntu 16.10 has a 4.8 kernel, and Ubuntu 16.04 has a 4.4 kernel. Work on supporting 4.8 is ongoing.

Sure enough, when I fired up a 16.04 x86_64 VM with a 4.4 kernel, I was able to build and install fine.

Connecting didn't work first time - the guest failed to mount, but I did get the following helpful error on the server:

LNetError: 2595:0:(acceptor.c:406:lnet_acceptor()) Refusing connection from 10.61.2.227: insecure port 1024

Refusing insecure port 1024 made me thing that perhaps the NATing that qemu was performing for me was interfering - perhaps the server expected to get a connection where the source port was privileged, and qemu wouldn't be able to do that with NAT.

Sure enough, switching NAT to bridging was enough to get the x86 VM to talk to the ppc64le server. I verified that ls, reading and writing all succeeded.

Next steps

The obvious next steps are following up the disabled tests in e2fsprogs, and doing a lot of internal performance and functionality testing.

Happily, it looks like Lustre might be in the mainline kernel before too long - parts have already started to go in to staging. This will make our lives a lot easier: for example, the breakage between 4.4 and 4.8 would probably have already been picked up and fixed if it was the main kernel tree rather than an out-of-tree patch set.

In the long run, we'd like to make Lustre on Power just as easy as Lustre on x86. (And, of course, more performant!) We'll keep you up to date!

(Thanks to fellow bloggers Daniel Black and Andrew Donnellan for useful feedback on this post.)