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bainsfather

You have to shoot them in the head, just aft of the eyes. About a 1 inch diameter target. That always kills them.

But if you miss, either by poor shooting or because they bob their head just as you shoot, then they often run off and you never find them. I reckon I get >> 90% kill rate, but that still means a few get away and suffer from the wound.

Re:Visual calculus on Tuesday February 13, 2024 @05:15AM (#39356239)
I've been considering reading this book - can you tell me what I might get from it in addition to what I learned in undergraduate maths/physics courses?

I found these courses allowed me to do calculations (e.g. contour integrals, conformal transformations) that were useful but always felt like black magic. I don't have an intuitive feel for the subject. I am wondering if this book will help me with that?

Re:I Face Investigation for Terrorism on Wednesday October 25, 2023 @03:29AM (#38010197)
2 years in prison, as I understand it.
Re:Risky Giant Steps Can Solve Optimization Problems Faster on Tuesday August 15, 2023 @04:09AM (#37131428)
I read the Quanta article because I am interested in optimisations for deep neural nets.

Am I right in concluding that your work doesn't apply to that area, as it is looking at a much 'easier' case?

None of our animals' waste is any hazard to you, unless you slip on it!

You are right that it can be done badly, as can many other things. I'd say you are actually arguing against badly regulated animal farming (especially since you mention the US), rather than animal farming per se.

I have learned something new today (re manure from dovecotes).

However, I think this is another example of something that is 'just too small to matter' in terms of feeding the world's population today. Often I see 'nice' stories about e.g. using human waste to fertilise fields, that quite frankly do not (usually) scale at all well. We (UK) use tractors to shovel and spread manure - 10s, 100s of tons of the stuff - a dovecote or 10 really isn't going to help, and certainly won't be economic.

It seems a bit like someone telling me I should use an abacus to increase my compute power - 'they were a good idea in the past, why aren't you using them now?'

Re:Use Gröbner Bases to Solve Polynomial Equations on Wednesday April 26, 2023 @07:38AM (#35712102)
A bit after halfway, following: "In this case, .. , and we have", I think you need a "-" sign rather than a "+" in your equation?
Re:The Little Learner: A Straight Line to Deep Learning on Thursday February 16, 2023 @03:21PM (#34825369)
Thanks. I see it for sale for £4 second hand, so maybe I should buy it for the novelty value alone. I presume I shouldn't try to refresh my java from it though.
Re:The Little Learner: A Straight Line to Deep Learning on Thursday February 16, 2023 @09:36AM (#34819158)
Is it still good? I see it was published in 1997.

I like the style of these books, and might read this one - I'm just worried that Java has changed quite a bit since then. Is it still, say, 90% OK?

Yes, this is true.

If we knew that this pandemic came from a lab, that would have massive implications for how tightly we control this type of lab research - both in terms of whether we do the gof research, and also in how we run and regulate the labs. Surely you can imagine the reaction if, hypothetically, the world knew that this coronavirus was made in a lab and then escaped?

I'm amazed that you think otherwise - it's one of the nice things about hn that I occasionally encounter views that are so different from my own.

Can anyone recommend a 'friendly' overview of the 'calculus approach'?

The paper linked in the article from 2003/2008 has been split up into 3 rather technical articles - I was hoping for something easier that just gave me a flavour of the method.

Re:Everyone should learn the slide rule (2021) on Monday April 25, 2022 @07:51AM (#31153218)
I bought myself a 2nd hand slide rule on uk ebay last year. Price was something like £5-£10 including postage, for a rather battered and 'cheap' example.

I really liked learning about it, seeing how it worked, etc. Such an ingenious idea!

So if nothing else, it might be worth putting them on ebay - there seems to be a market for them.

Re:Zero rupee note (2015) on Monday March 07, 2022 @06:29AM (#30586516)
Thanks! And that is from the "Construction Project Manager’s Pocket Book (Routledge Pocket Books)"? Presumably it has been added to the 2nd edition, because I cannot find that passage in my (1st edition) copy.

(edit - yes it is from the 2nd edition, thanks for your help)

Re:Zero rupee note (2015) on Monday March 07, 2022 @04:59AM (#30585963)
I did a text search of your reference [0] and it doesn't seem to contain information on bribery. (I searched for "bribe", and also "ethics" - which does exist but not in reference to bribery.)

Could you provide a(nother) reference to e.g. your 40% figure, as it is a topic that interests me? Thankyou.

Consider a different case ...

One can make a good case that Britain's guarantee to Poland in 1939 was done badly. Britain failed to convince Hitler that she was serious, and that invasion of Poland would lead to war.

We can agree that the 'blame' falls on Hitler. But one can also reflect on whether Britain's actions could have been better thought out, and maybe learn some lessons for the future.

In the case of Putin's Russia, NATO is dealing with a major nuclear power. Saying that Putin is at fault is fine. I very much dislike Putin. But we have to co-exist with Russia whether we like it or not. I am interested in reading some 'realpolitik' on this topic. In particular, I'd like to understand Putin's and Russia's motives, fears, ambitions, etc.

Re:The whistleblowing bankers who were sent to jail on Tuesday March 01, 2022 @04:30AM (#30511780)
I thought this was of interest because:

It illustrates the difficulties/risks faced by the insiders who are actually 'doing the dirty work', know what is going on, and want to stop it and/or blow the whistle. When the state is also part of the scam, being a whistleblower is very tough.

I am still amazed that the libor rate - something that was so 'easy' to manipulate - was the basis for many billions of dollars worth of derivatives. The 'foundations' of so many systems that our society runs on turn out to be shaky and easy to rig - not just IT systems.

Re:How to build homes with virtually no heating (2020) on Tuesday January 18, 2022 @05:30AM (#29977264)
I followed your link, but am confused and/or doubtful:

how do you replace 150mm of rockwool with 20mm of anything other than a good vacuum? It says that they are 'very low internal pressure' - but if it contains any kind of gas (which i presume it must do - air if nothing else) then the conductivity does not depend on pressure until the mean-free-path has increased to be > the width of the container.

Is this product real? What is it about the physics that I am not understanding?

And how do you maintain the 'very low internal pressure' over the decades that you will need it for?

Thanks.

Re:Group Theory via Rubik’s Cube [pdf] on Wednesday November 03, 2021 @05:26AM (#29092534)
I stumbled across this article last week. I've always wanted to figure out "for myself" how to solve a Rubik's cube. I've also always wondered what Group Theory was and what practical uses it might have for me - reading basic introductions to Group Theory never helped me much because I was never able to apply it to anything.

This article helped me with both - it taught me something about Group Theory in a 'practical use case'. And it gave me some pointers that helped me figure out how to solve a rubik's cube - several decades after I first picked one up as a kid.

In particular, I learned:

  - that if you repeat any sequence of moves enough times, you will always return to your starting position - with hindsight this now seems obvious, which I guess means that I've internalised some new knowledge.
  - that there are 'macros' - sequences of moves that shift just a few 'cubies' and leave the rest of the cube unchanged (I vaguely knew this already).
  - that there is a logical way to make such macros using 'almost commuting' pairs of sequences.
  - why I could never find a macro that swapped the positions of only 2 cubies (because such a move would be an odd permutation of the cubies, whereas moving a side (the basic move you can make with a cube) is an even permutation).
  - how to physically disassemble a cube, so that I could recover the solved cube - very useful when I was getting started with finding macros.
I didn't use the suggested computer solver/visualisation program, but wrote my own rough version - 'for the fun of it' (and also because it didn't run on linux).

Hopefully some others will find this as interesting as I did. If anyone knows anything similar to this for other 'practical' things besides Rubik's cube, I'd love to know about them.

Re:Banks, gangsters and the strange resurgence of cash on Friday October 22, 2021 @08:54AM (#28956633)
I know what you mean. In my case also, I think it is a combination of me being better informed about the world and the economist declining somewhat over time. BUT I started reading it 25 years ago, and still do read it a bit.

In terms of other news sources - I have no great advice. Here in the uk, I read the Financial Times - it is also rather international - maybe have a look at it. I would say that it is ok rather than great - but it is nice to get your news from more than one place. Private Eye is excellent, but mainly just for a subset of uk news.

I would like to have one "go-to" news source that I could rely on. But that is apparently not possible. So I read a few different things, and try to judge from their different stories what is really going on. Interestingly, I find that hn is a good source of quality information and insight, although it (of course) doesn't cover everything that I want to know about.

Re:Biochemical Pathway Maps on Friday June 25, 2021 @02:53AM (#27627867)
Thanks, I will.
Re:Biochemical Pathway Maps on Friday June 18, 2021 @05:09AM (#27548640)
I ordered one about 1 year ago, but never received it. Possibly because I didn't have a 'proper' organisation (e.g. a university dept) that I could list in the form.
Re:Scottish Café on Sunday May 30, 2021 @09:30AM (#27333098)
Stan Ulam's autobiography - Adventures of a Mathematician - talks a bit about this, from his early days in Lwow. It's a good book about interesting times and interesting people - if this wikipedia article interests you, then maybe the book will also.
Could someone explain what is being done here?

I see they are using a GAN, and doing unsupervised training. But then they appear to compare their model to supervised-trained models.

How do they do this? Do they tack a supervised-trained model onto the end of their unsupervised model? I imagine they must do supervised training at some point, else how can they convert sounds to text?

I have a distant relative who works for Springer Nature, and previously worked for Elsevier.

She's a nice person who I rather like. I have tried discussing the ethics of her employer's journals business in a polite way. She told me what I felt were the company's "talking points" - "well, publishing is actually quite expensive, we publish many more papers than we used to, etc" - all of which I think are not valid justifications - e.g. look at the huge profit margins of Elsevier. And yet I think she believes them, or at least "chooses" to believe them.

I find it rather depressing that someone, who is otherwise a fine human being, chooses to work there. I know quite a few other people in the same situation, in various other businesses.

Anyway, I thought it was worth mentioning what some of the people "on the dark side" are like, and that in the mirror they look rather like me and you in most respects. My opinion is that at work they are in an environment of people who all choose to believe the same thing, and so what they do is "normal" and "acceptable".

I follow cricket and (association) football quite a lot, and think I understand a fair bit of what goes on in games. But there are many things that I never notice, and that the commentators (especially in football) do not point out. So I liked this article because it showed me some of those 'hidden' facets of games, that I would not normally hear about.

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