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What would you call these units of measure?

TheDS

SOC-13
I created a unit of length equal to 3 meters, a unit of volume equal to that of a sphere 3 meters in diameter, and a unit of area equal to the surface area of that sphere, and I want a handy name to call them.

Frex, for length, we use meters. For volume we use kiloliters (which are cubic meters). For area we use the rather unimaginative square meters, but we COULD use centiares. (You've probably heard of a hectare, which is 100 ares. A centiare is 1/100th of an are, or 1 square meter.)

So I'd like less lame-sounding names than unit, square unit, and cubic unit.

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A bit of optional backstory, and what we have to gain from this:

For quite some time I've had a hobby of thinking about how to simplify the ship design sequence. Part of that involves getting rid of the dual volume measurement system of kl and Dtons and simply designing things in terms of one unit. I've also pondered a useful replacement for the displacement ton ever since the whole 13.5/14 kl snafu. And when I discovered decibels and how awesome they were, well, they simplify a lot of things like figuring out in your head the base stats of any hull from by knowing only a single two-digit number, so I had to make use of them.

One of the most annoying things about ships is having to use pi and a conversion factor to convert the length of a ship to its surface area or volume. Wouldn't it be nice if we could do away with all that? If all we had to do to figure out the area or volume was to simply square or cube the length of the ship? Well, it can be done, and if you stop caring about kl and Dtons, it becomes VERY easy.

All that needs to happen is to define 3 new units of measure, just like they did when they invented the Metric system. Now, traditional thinking might lead us to think that squaring and cubing our new unit would produce a square or a cube, but it doesn't have to if we include in our definition of the square and cubic the fact that we want the area and volume of a sphere. If you find this strange, I suggest looking up "circular mil". (Afterward, keep in mind we're not working with circles, we're working with spheres.)

The new unit, being a measure of length, could be converted to any other unit of length, such as the meter. The meter was originally defined as being 1/10-millionth the distance between the north pole and the equator, but you can convert them to inches by multiplying them by 0.254. Likewise, you can convert our new unit into meters by multiplying by something, but by what?

I chose 3 meters for three reasons. First, one "story" of a building, or the height of a deck, is generally taken to be 3 meters. Second, such a sphere is just a little over the volume of a metric ton of liquid hydrogen; in fact it's closer to the correct value than 14 is. Both of these reasons make it very easy to visualize. The third reason is a mathematical convenience, but explaining it would be a major digression.

The advantage of this system is that all you have to do to find an area or volume is square or cube the length, which you can often do in your head. No onerous formulas, no pi, no nonsense at all. You CAN of course convert these values into ca or kl if you need by multiplying by the conversion factors, which are 9pi and 4.5pi, respectively, but once you're comfortable using these units, you won't feel the need. Those of us not born to the metric system will recognize the feeling, but in this case, the process is much quicker.
 
Trile, triar, trivo...

More seriously, why not roll up 9 on your favorite alien wrod gen table, and use the three that feel right?
 
You might start by perusing some of the more obscure units of measurement and using one of those.

My personal favorite is the Saybolt Universal Constant or Second... ;)
 
Sorry, I'm going to be negative...

You haven't simplified anything. You have defined new units for length, area, and volume, let's call them ul, ua, and uv respectively.

1 ul = 3 m
1 ua = 4π(³/₂)² = 9π m²
1 uv = ⁴/₃π(³/₂)³ = ⁹/₂π m³

A Subbie has a cargo hold of 12 × 40 × 6 m, how many uv is that?
12 × 40 × 6 is 2880 m³, 1 uv is ⁹/₂π m³. The cargo hold is 2880/(⁹/₂π) = 640/π ≈ 203,7 uv. (Note that I cheated and made the calculations metric here).

Reversed: A rectangular cargo hold is 200 uv, how large is the floor in ua if the hold is 2 ul high?
A box with a side of 1 ul has a volume of 1 ul³. A sphere with a diameter of 1 ul has a volume of ⁴/₃π(¹/₂)³ = ¹/₆π ul³ = 1 uv, so 200 uv = 200π/6 = 100π/3 ul³. The floor is 100π/3 ul³ / 2 ul = 100π/6 ul².
A square with the side of 1 ul is 1 ul². A sphere with a diameter has a surface of 1 ua = 4π(¹/₂)² = π ul², so 100π/6 ul² = 100π/6π ua = 50/3 ua ≈ 16,67 ua.
The floor is 16,67 ua.

What is the mass of a 5 uv component made of solid steel?
Steel has a mass of about 8 kg/l. 1 uv is ⁹/₂π m³, so 1 uv of steel would mass 8×⁹/₂π tonnes or an even 113,097 tonnes.

How long is a 100 dT ≈ 99 uv wedge hull (Scout)?
Sorry, I'm losing my will to live here...


In order to simplify fairly unusual spherical calculations (slightly), you have made more common cartesian calculations much more cumbersome.


Note that no Traveller design system except FFS requires you to use π. Spherical calculations are already avoided...


So, I wouldn't call these new units anything, since I wouldn't use them.
 
... such a sphere is just a little over the volume of a metric ton of liquid hydrogen; in fact it's closer to the correct value than 14 is. T

The volume of a metric ton(ne) of liquid hydrogen is 14,132 liters (before boiling point). This figure "we" (read as Traveller fans the world over) accept fits into a (14m^3) 1 dTon. 14m^3 is another way of saying 2.14~ meters cubed or (2.1401m)^3. Maybe it was actually frozen? Or maybe, just maybe the dTon is actually based on (pure) water.

Your originality is great, but we could also just accept the existing numbers whether based on water or "hydrogen". Of course, your 3-meter standard and my 2.14-meter standard are not that far apart to really matter. It may seem easier to map ships. However, you set your scale to 1m=1 and I'll just set my scale to 2.14m=1. In reality, I am not sure you or I can change the Traveller player base any more than we can convert the US to the metric system.

Finally, I like your idea of 3-meter ceilings for the spacious interior they would provide in commercial starliners. However, I think the Imperial Navy may want to keep their 2.14m (or just over 6 1/2 feet) ceiling and load more ship systems. :)
 
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