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It’s an age of marvels

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Re: It’s an age of marvels

#91

Post by pfdietz »

perlgeek wrote: post #31
changoplatanero wrote: post #11

Earlier quoted context omitted.

The gps thing is even more amazing that what he said in the article because it turns out that the receiver doesn’t need an accurate clock of its own for it to work

That's right, you get rid of the requirement of its own clock, and instead accept that you need to "see" one more satellite than you'd need otherwise. The (oversimplified) mental model is this: If the receiver knows the exact time, and sees a signal from one satellite, it knows its position in one spatial dimension. For each satellite signal you add, you can determine the position in one more dimension. Once you get…

If the receiver has some internal sensors that can also help (gyros of various kinds).

I remember as a kid my father was working on the first version of the Air Combat Maneuvering Range (this was back in the late 1960s.) This involved dogfights with simulated missiles and guns. To work, the system needed to accurately track the position of the aircraft. Radars on mountains around the range would give good positions in two dimensions, but poor vertical position (this axis was nearly perpendicular to the line from a radar to a plane). The solution was to add a pod to each aircraft with various gyros and incorporate this information via a Kalman filter. Nowadays such a system would just use GPS, much simpler.

Re: It’s an age of marvels

#92

Post by dotnet00 »

bee_rider wrote: post #83
dotnet00 wrote: post #63

Earlier quoted context omitted.

It brings to mind the story of how when Boris Yeltsin was visiting the US, he took an impromptu detour to a random American supermarket to try to catch them off guard, only to be blown away that Americans really did have supermarkets everywhere practically overflowing with food. The story goes that the experience played a big role in shaping his vision for Russia when he went on to become its first freely elected lea…

Although, Yeltsin was already a liberalizing reformer. I wouldn’t be surprised if he was playing it up a bit.

Yeah, I do take it with a grain of salt since it's a very convenient propaganda story, and it'd be a stretch to say that he formed his political platform just 2 years before actually being elected.

Re: It’s an age of marvels

#93

Post by delta_p_delta_x »

criddell wrote: post #79
qlm wrote: post #35

Earlier quoted context omitted.

The quantity of chocolate for sale in bulk certainly is surprising. Unfortunately I find American chocolate to be borderline inedible.

That's like saying you don't like American beer because you tried Bud Light, Coors Light, and Miller Lite and didn't like any of them. There are a lot of great chocolate makers in the US.

> There are a lot of great chocolate makers in the US.

Ghirardelli are decent, but I've been relatively hard-pressed to find decent American chocolatiers otherwise. In general, European chocolatiers are in a different league.

Re: It’s an age of marvels

#94

Post by swatcoder »

ertgbnm wrote: post #23

More than anything else, I think the modern American super market would blow the minds of anyone born before 1900 more than any other marvel that exists. You have blueberries for sale in January??? A variety box of tea from 7 different countries? A wall of spices? Pineapples? Packaging made from aluminum that is just thrown away? The bread isn't full of sand and grit? And it's sliced!!! All relatively affordable and…

I agree that a modern grocer or butcher might wow them, but it's way less given that contemporary supermarkets would.

Those supermarkets are a product of a far more modern and culturally specific consumerism, which is not so innate as you might think. Many of us have been raised into and it's been gradually exported around the world, but it's the food equivalent of free to play MMO -- overstimulating, manipulative, confusing, and in many ways far divorced from the far more universal basics of buying food to cook and eat.

Re: It’s an age of marvels

#95

Post by throwup238 »

changoplatanero wrote: post #11
pfdietz wrote: post #2

I believe GPS also uses multiple wavelengths to allow estimation of signal delay from passage through the ionosphere. The way Martian meteorites are identified is from isotopes of inert gases (neon, argon, for example). Mars has a particular pattern of these that's been measured by landers there. Meteorites from the moon are identified by oxygen isotopes, which are on the same line on the oxygen isotope plot as Earth…

The gps thing is even more amazing that what he said in the article because it turns out that the receiver doesn’t need an accurate clock of its own for it to work

On top of that, with modern surveying and an RTK GPS base station you can get centimeter accuracy for very precise measurements of land, all by carrying a stick with a receiver on it. Most populated counties in the US already have a network running so you usually just need the receiver.

Re: It’s an age of marvels

#96

Post by Folcon »

brigadier132 wrote: post #75
keybored wrote: post #53

Earlier quoted context omitted.

> It really is amazing, that's why we really need to appreciate and protect what we have. The incredible abundance we currently have is not the norm. It was not even 100 years ago that people were starving in the US during the great depression. This is fine and a good exercise (like a gratitude journal). The problem is that this is often used to tell people indirectly that they should stop with their political compla…

> The problem is that this is often used to tell people indirectly that they should stop with their political complaints It's a tell that you conflate political complaints with extremist violent rhetoric.

I would say that in this forum we try to be charitable to each other and it's certainly the way I like to conduct myself.

The poster you're replying to has so far merely provided you with an opportunity to clarify or expand on what you would consider "extremist violent rhetoric".

We're all pretty curious people here, and I would say reasonably opinionated, so I don't think it's unreasonable for someone to ask you to clarify your position.

We're not going to get to the high level of discourse we like and expect in this space without a bit of curiosity and generous assumptions to our fellow posters =)...

Re: It’s an age of marvels

#97

Post by Nasrudith »

paulryanrogers wrote: post #85
more_corn wrote: post #76

Earlier quoted context omitted.

And yet a lot of people go hungry in this age of marvels. We have enough homes to house all the homeless, we have agencies, money, social workers. And yet we somehow can’t seem to figure it out.

We can. It's just uncomfortable to admit. For example, making housing an investment steals from the poor to give to the rich.

You can frankly tell when something is bullshit when it involves defining new increasingly fantastic and phantasmal forms of theft. It inevitably devolves into some sort of bastardization of voodoo.

Just looking at the number of houses and the number of homeless is itself deeply misleading for what should be fairly obvious reasons. If someone operated a model simplistic enough that concluded there should be no deaths of dehydration in Africa given the flow rate of the Nile river is more than sufficient to hydrate them, you would call said hypothetical person intensely dim for believing that conclusion or model of reality. Yet when it comes to housing suddenly that incredibly over-simplistic to the point of being idiotic model it becomes a political rallying cry.

Re: It’s an age of marvels

#99

Post by keybored »

brigadier132 wrote: post #75
keybored wrote: post #53

Earlier quoted context omitted.

> It really is amazing, that's why we really need to appreciate and protect what we have. The incredible abundance we currently have is not the norm. It was not even 100 years ago that people were starving in the US during the great depression. This is fine and a good exercise (like a gratitude journal). The problem is that this is often used to tell people indirectly that they should stop with their political compla…

> The problem is that this is often used to tell people indirectly that they should stop with their political complaints It's a tell that you conflate political complaints with extremist violent rhetoric.

Like I said, when you vaguely point to something in the Zeitgeist I have to guess. I made my assumption clear so don’t try to make this into a gotcha.

Specifically extremist, violent, political[1] rhetoric is subsumed by political complaints in general. So if you mean conflate as in draw an equivalence then that is clearly a wrong inference on your part.

[1] This adjective wasn’t in your original comment hence my guess.

Re: It’s an age of marvels

#100

Post by keybored »

afthonos wrote: post #90
keybored wrote: post #53

Earlier quoted context omitted.

> It really is amazing, that's why we really need to appreciate and protect what we have. The incredible abundance we currently have is not the norm. It was not even 100 years ago that people were starving in the US during the great depression. This is fine and a good exercise (like a gratitude journal). The problem is that this is often used to tell people indirectly that they should stop with their political compla…

As far as I use the term, extremists are people who advocate for tearing the system down via revolution and rebuilding from scratch. They have no idea what it takes to build this modern world, but they love the idea of guillotines.

Some people complain about taxation on tea or the lack thereof instead of appreciating how privileged they are to have access to Oriental tea.
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