Recent submissions

Comment · 1 year ago
Comment · 1 year ago
"A study using a complex mathematical technique claiming to cleanly isolate the effect of X and Y. I can't really follow what it's doing..."

This is a frustrating type of issue. Dismissing something with "I don't understand this, but I don't believe it" isn't the sort of thing I want to be doing. However, I don't have any desire to waste time trying to understand what someone has done (and did they really understand what they were doing themselves?) when it's clear that the effect isn't cleanly isolated in the data and no amount of mathematics is going to change that.

Comment · 1 year ago
Yeah, I'm always a bit suspicious of apparently effective dietary changes which result in a calorie reduction - often different people report completely different dietary changes helped them, but one thing they all have in common is being in calorie deficit.

There are plenty of studies showing that caloric restriction calms inflammatory responses which are responsible for the majority of common diseases. Without balancing the energy intake, I'm always slightly suspicious that any improvements with changing what I eat are actually caused by the change in how much I eat.

Comment · 2 years ago
I don't see why that means there's anything off. Just because most of us can't produce enough energy per unit time to maintain this pace doesn't mean that it's not the most efficient pace per unit distance.

Anecdotally, when I start (or re-start) running I find the pace I can run at increases quite rapidly. That makes sense with this data - although my fitness is only increasing slowly, being able to produce slightly more power actually gives a disproportionate increase in pace because the higher speed is more efficient per km.

Comment · 3 years ago
Comment · 3 years ago
Yeah, the potential loading is annoying. I remember wondering why predestrian/cycle bridges were always so annoyingly narrow despite having low loads. The issue is of course that they have to be strong enough to support being crammed with hundreds of people when everyone is there to watch the local fireworks/rowing race/anything else that's happening, even if that happens almost never.
Comment · 3 years ago
Comment · 3 years ago
That sounds massively expensive. Being very generous and assuming that the piston is the length of the hole and can rise out completely, then the energy storage is still only a few times that required to pump all the water out of the hole. It doesn't start to compare to the volume behind a hydro dam (which may then have a large vertical drop to the generator further down-river), but is still much more complex.

Another proposed idea for places that have deep seas or lakes is pumping air down into a storage at the bottom of the water. This storage can even being a flexible plastic - there isn't any high loading on it because the pressure balances out. The issue with that tech is that it's not that efficient, as compressing the air going down generates a lot of heat - some of that could potentially be recovered, but there's a trade-off with simplicity. Also if the containment fails then a lot of air bubbles to the surface, potentially sinking any ship on the surface at the time.

Comment · 3 years ago
It's surprising how well these ships sail; although square sails are often thought of as only being effective going down wind, they sail somewhat into the wind fine. And of course, you don't have to worry about a bad gybe removing your rigging. I was in Norway a few years back and took a tourist trip in a 2/3 replica of a Viking boat found in a burial mound - the crew took us up the lake, turned round and came straight back - it was remarkably nippy and seemed to handle very well. I'd be interested to read how the much larger ship here performed under sail.
Comment · 4 years ago
Comment · 5 years ago
I'm more of an in-office person. The office is definitely more distracting, and I used to like working late occasionally because I had some solid focus time, but to a degree that's still true: whilst other people are online there is necessary interaction to transfer information in both directions.

One potential WFH efficiency loss for me is that due to casual conversations or things I overheard in the office, there were many occasions when I knew that someone had already investigated something or that some issue had come up that explained symptoms I came across, saving unnecessary duplication of effort or implementing something which wasn't quite what was required. You might argue that this level of communication could be achieved remotely, but maybe you'd end up with nearly the same level of distractions.

I will add that my commute was a 15-minute cycle, and my employer provided me with lunch, so probably going to work was actually a net time saving for me (certainly if you consider the commute exercise time), which may explain why I'm less keen on WFH than most.

Comment · 5 years ago
From the employee's point of view, yes. From the company's side, not really. Which may explain to some degree why workers are more likely to feel that they're more efficient working from home - they consider the commute part of the workday, and the employer doesn't.
Comment · 5 years ago
Tidal energy doesn't compete with wind, it competes with energy storage. Having virtually no wind production over the whole UK for a week happens regularly; in fact this last week is a good example - production has averaged well under 2GW according to https://www.gridwatch.templar.co.uk/ On a windy week production can average over 10GW, but as yet grid scale storage is about as immature a technology as tidal generation (with the exception of pumped hydro, and there is a limited number of suitable sites for that).
Comment · 5 years ago
My hair recently went significantly less white - a significant fraction of the hairs that I vainly plucked because they were white at the tips were dark at the roots. It correlated with a significant change in diet to eat more healthily, but I've noticed it happen before so it may also be seasonal or related to some other factor such as how stressed I am or how well I am sleeping.
Comment · 5 years ago
Do you have some data showing that the amount of carbon stored in Siberian forests has a more significant warming effect than the methane escaping from the warming ground?

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