### Give a Man a Fish...

What we have done for ourselves alone dies with us; what we have done for others and the world remains and is immortal.  - Albert Pike

There's an unwritten rule of blogging that you shouldn't talk about long periods of not writing. It's a good rule but, as with all rules, it's best thought of as a rule of thumb, and not to be taken as gospel.

Today, I want to give an account of my lack of activity over the last months, and to tell you all about something really exciting that I've been involved with.

As some of my regular readers will be aware, I became aware of a local project, ostensibly run by the Catholic church, for young people in one of the most deprived areas in Manchester. It began as a youth project some seven years ago, and is notable for, among other things,  having lasted this long. Most projects of this nature tend to die a natural death within about eighteen months or so, but this one keeps going and growing.

It's a fantastic project, using music as a means of generating positive aspirations, confidence, and a sense of family. We have a tight-knit group of young people who come and learn to sing, play instruments, and perform at all sorts of events, mostly charitable, or in aid of other projects broadly like ours. We have an industry-standard recording studio with live room, amp boxes, vocal booth, and a large hall with a stage.

I became involved as a volunteer mentor, delivering vocal coaching, instrument lessons, etc. and due to my past experience as a photographer, I've become responsible for the project's media, taking pictures, shooting video, and teaching film-making and editing to the young people. It's a perfect fit

One of the reasons that the project is still going strong, and growing, is that it's somewhat cyclical, with new members coming through from primary school and integrating with members from all the high schools in the area, and with older members becoming mentors themselves, developing these skills during their tenure with the project. It grows and grows, and we do some fantastic work, both in the furtherance of the general aims of the project, and in helping other projects to achieve their aims.

We're now becoming something of a go-to for other projects and charitable organisations for music and media for their own purposes. For example, earlier this year, we were commissioned to record a song for CAFOD's (Catholic Agency for Overseas Development) 'Earth Day' celebrations. They requested a reworking of John Denver's It's About Time. We duly delivered this, along with a video for their use. This was achieved with the help of some stellar people (pun intended), such as NASA, The Clean Ocean Project, Peter Bowdidge, the Australian Broadcasting Corporation and others. I'll pop the video in at the bottom of the page.

One of the projects that CAFOD are involved in is the real reason for writing this piece, and my intent is to raise awareness of the project and hopefully direct some to its just giving page.

Let me talk for a while about the developing world, and some of the problems faced by its denizens.

In some parts of the world, just getting the resources you need to survive day-to-day is a full-time occupation, by which I don't mean a thirty-five hour working week, but actually full time, as in all the time you have available. This can present some real problems, not least because if all your time and energy is taken up trekking tens of kilometres a day for water, there's little left for the one thing with the potential to lift you out of that cycle; education.

The worst hit by this cycle are girls and young women, to whom the brunt of this responsibility falls based on the patriarchal structure of their (and our, lest we forget) society. Even where education is available, it's problematic, because of the time required just to get water, and being able to read at night requires light sources which, without an efficient and reliable energy supply, is a pipe dream. Additionally, because of the cost of getting power to these remote areas, even where there are schools, energy is expensive to acquire, even to the degree that schools struggle to maintain themselves.

It's estimated that somewhere in the region of 1.3 billion people in the world have no access to power. Of those, on the order of 170 million live within a kilometre or so of a river.As is often the case, where complicated solutions are impractical or expensive, an extremely simple solution can tick all the boxes and even generate new boxes to tick.

Enter the River Power Pod.

 Image courtesy River Power Pod Ltd
This is the kind of idea that should, to a thinker, elicit the kind of response that Huxley uttered on first hearing about evolutionary theory. It's so simple, one wonders why it took a Charles Darwin to come up with it. That's not to say that it doesn't represent engineering challenges but, at bottom, it's among the simplest notions.

The River Power Pod is a portable turbine. Properly, it's an in-stream hydro-turbine, which is geek-speak for 'you dunk it in a river and it generates electricity'. This electricity can be used to charge batteries and drive energy-efficient LED lights, among other things, making education attainable for people who previously had little no access.

And it doesn't end there, either. Indeed, we've barely scratched the surface. Other issues often faced in remote areas, especially in the tropics, is drought. Fields lay dry, dusty and unproductive, with the infrastructure for reliable irrigation also being expensive and labour intensive, putting it well beyond the reach of many. This, of course, all adds to the cycle. Power, fresh water and reliable sources of food staples, things we barely have to give a second thought in the first world, in which our most pressing concern is often whether we'll get home in time for Coronation Street or, at least, comparably trivial by comparison.

The brainchild of a clever boffin from Lancashire in association with several UK universities, the River Power Pod can be employed to drive pumps, delivering fresh water and irrigation to remote areas. Further, in some places, such as Kenya, many are relying on kerosene for light, cooking and heating. This has some fairly obvious problems. Kerosene has been classified as Xn (harmful) by the World Health Organisation. Ingestion is generally not problematic in acute cases, but chronic exposure and particularly inhalation, especially in elevated temperatures and/or enclosed spaces, has been shown to cause central nervous system depression, a symptom of inhibited brain activity. This is a serious condition with symptoms including shallow respiration, reduction in heart rate, irritability ataxia and loss of consciousness, which can in turn lead to coma and/or death.

Moreover, kerosene is, in terms of the average income in these regions, horribly expensive. Any solution that frees up that income means that it can better be spent on education and other social improvements.

The River Power Pod has been tested in all sorts of environments, and has had some commercial interest (it has to be sustainable, after all), not least from power companies and governments across the world. For example, in conjunction with Practical Action, an international development charity, the power pod has been assessed such places as the Terai in Nepal for early warning systems for flash flooding. Such early warning systems have been in place for some time but, due to the kinds of issues faced in getting reliable power supplies to such places, powering early warning systems has been problematic. The River Power Pod is perfect for such a situation, as it's robust in wet environments, meaning that early warning systems can be made reliable, leading to timely evacuation in flood-prone areas, saving lives.

It's in Embu, Kenya, that the River Power Pod is getting a chance to properly stretch its legs. Ged Heffernan, former physics teacher and one-time manufacturing lead for Rolls Royce and for Mercedes in association with the McLaren F1 team and with indycar, tells me that among the biggest problems faced in addressing some of these issues in the past is simple reliability. Such problems can be catastrophic, and leave people worse off than before the attempt was made. Being unable to take care of energy-generating infrastructure, when systems break down, people whose aspirations have been lifted by the provision of facilities are left in total dejection when those aspirations are removed. Thankfully, he has a plan for that, and it's a doozy.

Working in conjunction with two local schools and a technical college, Ged, along with his colleague, Caitlin Thompson - a masters graduate in physical geography from Lancaster University - is training young men and women to build and maintain the pods themselves. This has the interest of the Kenyan government and, once up and running, will lead to a local industry worth real money to people in a sorely deprived region, and a firm future. This will also have the adding bonus of getting girls and young women involved in STEM subjects, something largely denied them at the moment due to the perpetual cycle of subsistence.

This is a pilot project, of course, and a proof of concept. The hope is that, if successful - and, all things considered, there's no good reason to suppose that it will be anything less than a roaring success - this will provide a means and a model to bring sustainable, renewable power, as well as fresh water and a means of irrigation, to some of the remotest and most deprived regions on Earth.

I caught up with Ged so that I could ask him some technical questions for the nerds among my readers.
Overview: The device is scalable, so we can make them in any diameter from 100mm to multiple metres – a 1 Megawatt unit in a healthy flow would be around 15m diameter. We can make smaller in-pipe units of 10s of mm . However as our device is a hydro-kinetic turbine we are focussed upon the kinetic energy available for conversion and that is only a squared relationship with the cross-sectional area of the turbine; we are far more excited by the velocity of the flow as the available kinetic energy has a cubed relationship with this – I always like the raw fact that doubling the velocity of the flow gives you eight times more energy! For this reason we hunt out faster flowing water for our high output locations – nature is kind to us on this as even a slow river often has narrow sections where it passes through rocks or other obstructions – slightly over simplified, but halving the cross-sectional area of the river at a point can double the velocity hence yield eight times as much energy from the same turbine placed in a wide part of the river. But rivers are not simple, and there are areas of high and low velocity in the same cross-section of river; e.g. other than variations in riverbed and riverbank features, the outside of a bend, close to the riverbank, is often the fastest flowing element – handy for easy exploitation as you can hang the turbine in the river without the need for expensive bridges/foundations and without the need to get in the water! (Desirable in a number of the locations we work due to the alligators, hippos, and river-blindness bugs!) The location we have chosen for our first Kenyan turbine is a natural flume created in the river by a collection of large boulders. It is also possible to speed the river up by creating an artificial flume where there isn’t an undesirable environmental impact – this can be done using local material such as rocks or by simply creating panels from timber. We are currently assessing a site in the UK where someone is looking to create a zero-carbon home on an old mill site that we can use as a research site for further work with schools and universities. This site has a fairly low volume of water flowing through the site but we are surveying the site for natural flumes where the velocity is high and the cross-sectional area sufficient to viably insert a turbine, as well as locations for collation of groundwater and harvested rainwater.

Hackenslash What's the output of the pod?

GH A function of turbine diameter and flow velocity
i. $Pa = ½ C_p ρ A v^3$ • $A$ = area in metres squared ($m2$) • ρ = density of water $(1000 kg/m3)$ • V = velocity of flow ($m/s$) • Cp = the power coefficient = $16/27 = 0.593$ (Betz limit - theoretical maximum power available)

ii. Our turbine has demonstrated up to 0.55 (That’s very good up at 93% of the theoretical limit!) • Turbulence and matching the load to the available energy play a major part in achieving optimal efficiency – a loaded turbine runs at half the RPM of an unloaded one but extracts far more energy from the flow. b. In the right conditions, one of our 250mm diameter turbines has the potential to produce up to 1.5kW electrical output in a 5m/s flow when matched to a decent generator. The one inside the boat, a 300mm turbine has the potential to achieve 2.2kW in the same conditions. That figure rises to 6kW for the 500mm unit we are taking to Kenya.

Hackenslash What sort of minimum flow is required for significant output?

GH In tank-testing at Lancaster University the turbine began to rotate at just 0.3m/s and technically produces power, but, as mentioned above, output is a cubed relationship to velocity so the power is very low at this velocity – unless of course the diameter of the turbine is high. b. 0.7m/s is our slowest viable velocity as the friction in drivetrains tends to be too high a factor below this velocity. In a slow river in Stafford, running at 0.7m/s, the yellow 250mm turbine charged our phones. c. There isn’t a typical flow velocity for a river as there are so many factors and it is really down to choosing a spot – even rivers in the UK that run around 1m/s for the majority of their flow have points where they are running up to 3m/s (e.g. River Eden in Carlisle where we conducted our STEM day with a local school) d. The highest velocity we look for is currently 5m/s as it gets a bit ‘tasty’ to work in anything higher than that – but we will be assessing locations with potentially higher flows while in Kenya.

Hackenslash what's minimum operating depth?

GH A simple function of the turbine diameter – we usually recommend an envelope that is double the diameter and three times the length of the turbine being used. b. A 100mm turbine could operate in as little as 200mm of flowing water c. The 250mm turbine runs at its best in a depth of 500mm, but our turbines still operate (albeit at lower efficiency) when only a third of them is submerged in flowing water! The yellow one started to light up the load-cell when it was only partially submerged and at 45 degrees to the flow when we were demonstrating in Kenya. Little monsters – really difficult to stop them; even rotate in wind when it’s strong enough!
I think, dear reader, that it's a bit of a no-brainer. This is something we should, if we're concerned about the future and well-being of our species, get behind with everything we've got. It's a genuine game-changer, and has the potential to have the sort of world impact that most of us can only aspire to.

Please share this article among your friends, and especially see that it gets in front of anybody who is anybody, anybody who can exert influence, or money, or publicity, or anything else that might help make this project fly.

The project's JustGiving target is a mere £62,500, and is more than two-thirds of the way there already.

You can also find news and details of the project at their Facebook page, and on Twitter, as well as the company's own website.

Let's help to change the world and leave it better than we found it.

Asante sana!

### Does My Class Look Big In This?

It's all a matter of style... or is it?

I'm almost certainly going to ruffle a few feathers with this outing, so brace yourself, dear reader.

It will come as no surprise to regular readers of my various musings that I'm a massive advocate of education. It's my deepest passion, and the reason that I embarked upon this project. Above all, I advocate a scientific, evidence-based approach to all things- education included - and this is the motivation for this current outing. This one's taken a fair while to write, not because of the writing of it, but because of the research involved and because I wanted to be sure I didn't miss anything. I'd already pretty much written it and then decided that I hated the approach I'd taken and decided to scrap it and start again only a couple of weeks ago.

There's been a battle raging in educational circles for some time. Those outside education will probably not even be aware of it, but it sometimes gets quite intense, with lines drawn, colours raised and blood spilled - figuratively, of course - and the passion borders on religiosity, which seems to make this a fitting topic for this blog. It's also going to be something of a treatment of some manifestations of our old friend cognitive bias.

There's a common idea that began to surface some time in the early 1900s - shortly after the introduction of the first intelligence tests by French psychologist Alfred Binet - that essentially states that we all learn in different ways. It's an extremely attractive idea, and seems on the face of it to be fairly obvious.

Those who've been paying attention to my output will currently be hearing the awuga waltz playing in their heads, I suspect (and hope). When something's obvious, that's often the first sign that we need to be taking a closer look at it. The name given to the idea that something being obvious means that it must be true is 'appeal to intuition'. I've come across some discussion of whether this should be considered a fallacy, but all such discussion is specious, as a brief exposition should demonstrate readily.

It's intuitively true that time runs the same for every observer except that, if this were actually true, satellite navigation would be a pipe dream. It's intuitively true that something can't be in two places at once except, if that were true, the technology I'm employing to share my prattlings with you today wouldn't even rise to the level of fantasy. It's intuitively true that I can't walk through a wall - and indeed I've never managed it yet- except that, if this were actually true, we couldn't exist, because fusion in stars wouldn't occur, meaning that elements heavier than beryllium couldn't be synthesised.

So, returning to this idea, popularly known as 'learning styles', the initial inklings followed directly from Binet's work, first by Maria Montessori, well-known for the Montessori Method of education. Montessori began to develop specialised educational materials based on her work with children with special educational needs. After initially gaining some traction, not least via an association with an Italian Baron and Baroness, this idea fell into disfavour, festering in the recesses of public consciousness.

Then, in the 1950s, it began to resurface. By the 1970s, it had begun to find favour globally until, by the early noughties, it was fairly widely accepted.

I don't intend to delve into the history of this idea in this post (and probably not in any other), not least because it would make this offering massively unwieldy, so I'll leave it there, noting that the wiki on this topic is pretty comprehensive.

So what is 'learning styles' really?

Broadly, it's the notion that we all have particular preferences for the way that educational material is presented, and that these preferences translate to differentials in the way that effective learning is achieved. The idea is that some of us learn best when material is presented visually, others learn best from text and still others learn best from tactile presentations or by doing.

It's certainly a meretricious notion, but does it hold water?

While it's certainly true that students will tend to latch onto those modes of learning that they feel most comfortable with, it's less clear that this is actually a good way of structuring learning, as a little careful thought should elucidate, so let's pull it apart and give it some real consideration.

The best place to start is, I think, a simple principle that can be presented in many ways. Such things aren't that easy to find, it turns out, but we're quite lucky because we have one to hand that we've encountered a few times hereabouts, and it's one that is familiar to schoolchildren everywhere: Pythagoras' Theorem.

We'll begin with presenting this as simple text in the way that it was first presented to me.
The square on the hypotenuse of a right-angled triangle is equal to the sum of the squares on the other two sides.
This seems to be fairly straightforward, albeit with a couple of undefined terms. Of course, once you know that a right angle is an angle of 90°, or a square angle, and that the hypotenuse is the side of the triangle opposite the right angle, it becomes fairly clear. However, it might not be visceral, so let's try a more mathematical approach.

Here's the same theorem presented as a mathematical equation: $a^2+b^2=c^2$

Interestingly, to the non-mathematician, this conveys less information than the purely textual example given above. To somebody comfortable with mathematical presentations, however, this conveys every bit as much information and, moreover, requires no additional information, and contains no ambiguous or ill-defined terms.

As an aside that some might find interesting (who am I kidding, anybody who really finds this interesting probably already knows it), this is also the root not only of how relativity theory works, but is also the foundation for Fermat's Last Theorem, one of the great unsolved problems of mathematics, until a solution was found by Andrew Wiles*.

OK, so it could be reasonably argued that both of those presentations are textual, albeit in different languages. How about a visual presentation? Here's one that we've used a couple of times before:

Well suddenly, it all becomes clear, so it must be the case that we ALL learn best from visual representations, yes?

Let's circle back to that, because doing so will be instructive for our purposes.

Let's finally do something that's pretty much impossible when your medium is a two-dimensional surface, but which we must attempt to get past, namely the kinaesthetic presentation. Let's see what we can learn by doing:

Of course, this is still a visual presentation but, with a little imagination, we should be able to get the gist of it. We could easily imagine building this from wood and glass and filled with liquid so that it could be physically turned. Indeed, this has been done:

This covers a fair bit of the content of learning styles, and it can seem that there's something here for everybody, no matter what one's preference for information acquisition might be. It would be hard, on the basis of the foregoing, to see what objections might be raised against it.

That fact alone should serve as a warning. As we've discussed in quite a few different contexts, the things that should be most vigorously challenged are those that we think are obvious, and we should think hard about whether our underlying assumptions are actually correct.

Let's jumble them up a bit, and see where that gets us. Let's start with the purely visual iteration.
What can we learn from this alone? The short answer is absolutely nothing. Without the context given by the textual example that preceded it, this only works as a way of learning Pythagoras' Theorem if you're already aware of the underlying geometry. It isn't clear, for example, that the squares on the adjacent sides bear any relationship to the square on the hypotenuse, let alone that their areas are equal. If you don't know what's going on, you can learn nothing about the length of each side based purely on this image. It requires additional information.

How about the mathematical example? Let's see it again. $a^2+b^2=c^2$

What can we learn here? Again, in isolation, and without context, we can learn nothing. It requires additional information.

OK, so what about the text?
The square of the hypotenuse of a right-angled triangle is equal to the sum of the squares of the other two sides.
Have we learned anything useful from this on its own? Of course not because, as we've already highlighted, there are ill-defined or undefined terms in there and, absent those definitions, which must themselves be learned, we can't hope to make head nor tail of this.

Only one of those representations, on its own and without reference to any outside information source, actually gives us the meat of Pythagoras, namely the kinaesthetic, or 'touch-based' approach. From that, it's really clear what's going on. It's obvious to pretty much anybody, yes? So must it be, then, that we all have the same learning style?

Let's think about it a bit more carefully.

How about if we combine these modes. We can take the prosaic statement of Pythagoras' Theorem  and combine it with, say, the algebraic formulation, and it becomes reasonably clear. Or we can take the algebraic formulation alongside the visual geometric representation and the information conveyed seems complete. The same is true if we combine the text and the geometric representation.

So what about if we combine all of the above into a single unified lesson on Pythagoras' Theorem? The answer should be reasonably clear. If we were to structure all of this information into one lesson, all the cues would be there, and pretty much everybody should be able to walk away understanding how it works, and able to see a route to calculating the length of an side of a right triangle given only the lengths of the other two sides. One could even see that, given only the length of one side and the one none-right angle adjacent to it, one could construct a complete right-triangle.

I'm once again aware that this is turning into a somewhat lengthy offering, so I'll finish with an anecdote.

I was watching the latest episode of one of my favourite shows the other night, Suits. This isn't my usual kind of thing, and I tend to stay away from this sort of drama, but the central character has an eidetic memory, and this is something that's always fascinated me (were I to choose one trait allowable by evolution, this would be it), so I have a tendency to watch anything containing such a character, because it's always interesting to see how it gets treated and how the memory is used in the plot.

It's a mildly entertaining legal drama set in a high-power legal practice in New York. There was a scene in it in which an associate gets bawled out for handing off a piece of work to a younger associate. She raises the excuse that the younger associate is better at the kind of work this involved. It was pointed out that the reason for giving her the work to do in the first place was that she needed to improve these skills.

And this brings me to the central point. All of these 'learning styles' are skills. Indeed, learning is itself a skill - something that must be learned. Different ways of absorbing information must themselves be learned. If anything, the notion of learning styles should be seen as a guide to how NOT to do it. If you have a student whose learning style is visual, it's actually counter-productive to rely solely on visual learning cues, because this encourages cognitive pathways that exclude other routes to learning, and are ultimately destructive to the learning process. Far better to focus on the kinaesthetic and text-based approaches, using visual cues only as a secondary or tertiary approach as an additional learning aid. The same is true of the other styles, in that the preferred approach is almost certainly best used as the last resort.

Most of my readers know me as somebody who can distil very difficult concepts into simple, accessible terms. This can be quite a challenge, especially when dealing with cutting-edge physics and other lofty topics. In reality, most of those topics are best presented in a very specific way for clarity, in the language which best describes the processes involved; mathematics.

Mathematics is difficult for many, and their eyes glaze over at the first sign of an exponent. Indeed, I used to find this myself, but forced myself to keep plugging away, even if it took me a week to get through the meat of an equation so that I could solve it. It's still a slow process for me now, but the depth of understanding I have of the processes I've had a fairly visceral grasp of for years is increased by orders of magnitude just from understanding the structure of the equations and how the quantities in the universe are related numerically. I know from discussions I've had with people who've questioned me on some of what I've presented in this blog that, as simple and straightforward as my presentations are, there are still who firmly grasp the wrong end of the stick. There's only one way to remove ambiguity, and that's to move away from natural language entirely, and cast the entire discussion in terms of the mathematics. In other words, there are some kinds of information for which there is only one rigorous way to present them.

Now, I have no doubt that, in some settings, especially in settings in which special educational needs are manifest, that the framework of learning styles is useful, and that there are students who benefit from it greatly, in that they can achieve a level of education that might have been denied them via more general teaching methods but, as a general teaching method, it sucks.

More importantly, from the perspective of somebody interested in ensuring that evidence is the final arbiter of anything taken as fact, there is no evidence beyond the entirely unreliable anecdotal that it's anything other than an attractive cop-out.

Of course a student who likes visual representations is going to say that they found that learning via visual cues was easier. This is really not the point. I'm perfectly happy to accept as true the idea that different people find learning more readily when the material is presented in different ways. However, the simple fact is that, as a general approach to learning, it's counter-productive. Offering a sop in this manner closes the student off to the acquisition of skills in other areas and, for those kinds of information that lend themselves to only one way of being unambiguously presented, it closes them off from those subject areas entirely.

All of these are skills, and can be acquired.

If you're really interested in what the evidence says about effective learning techniques, I recommend keeping abreast of the research. Here's a nice presentation from the Learning Scientists.

Nits and crits welcome as always.

*Fermat's Last Theorem is a famous problem in mathematics. It states that there are no solutions to the equation $a^x+b^x=c^x$ where $x$ is any integer greater than two. It was one of the famous 'Hilbert' problems - named after David Hilbert, the German mathematician who listed them - a list of 23 of the great unsolved problems of mathematics compiled in 1900. This problem was ostensibly solved in 1994, although my good friend Phil, author of Definitions and Axioms, had this to say back in 2015:
Wiles' proof can only be checked by a tiny handful of mathematicians on this planet. That puts it very much in a "doubtful" place by the standards of pure maths. I doubt the average professional number theorist could check Wiles' proof.
Wiles won the Abel prize for his proof in 2016.

It's fairly certain that Pythagoras had little to do with this theorem. It was certainly understood as a general principle before Pythagoras, but the formal description of the principle comes from the Pythagorean school.