[Terrapreta] Where to get the right charcoal?

[code suidae]

On 9/25/07, ch braun <brauncch at gmail.com> wrote:
>
> Thanks a lot for your (very constructive!) comments.


I'm glad you find them helpful. When you posted the links to the xml spec I
started a UML model of it to see if I could understand it a bit. I have an
idea to write a little windows utility program to keep track of char
experiments. I figured if I use your model for describing the data it will
make getting my results into the database completely painless.

We've got two different things going on here. I think the purpose of the XML
spec is for portability (yes?), so users can sync data between their local
systems and a common database (upload to send their own results, and
possibly download for off-line use of other's data). The entity
relationships aren't and shouldn't be dictated by the XML spec, so, if you
don't object, I'd like to step up away from the xml/database representation
for a moment and just discuss the entities to be represented and how they
relate to each other.

I'm resistant to the idea of keying a kind of charcoal by the user. Ideally
the details of the method and the feedstock should be sufficient to describe
(and reproduce) a kind of charcoal. In practice it may be that quirks of the
way a particular user produces the charcoal has an effect, but those quirks
are a property of the production method, not of the user.

compared with my proposal your changes for the parameters are:
> * you added:
> - title
> - target temp
> - description
>
> * you removed:
> - mode (whether it is bought or selfmade)
> - minimal temp
> - peak temp
> - heating rate
> - duration
>
> For my point of view these were all "static" parameters? By target temp
> you mean average temp ? otherwise is that not the same as peak temp?


When you make cookies you have a recipe that specifies the ideal temp you
should use, but when you actually bake them you might not achieve that temp,
or you might have a temperature profile that deviates significantly from the
idea. I'm trying to capture that relationship. Each dynamic char event is a
little different, but is performed according to a certain static recipe.
Rather than try to create 1000 different recipes capturing information like,
'the wind was blowing today so it ran a little hot, but was otherwise the
same as the other trials', I think it makes sense to have some standard
procedures that users define and follow, and then note deviations. If the
deviations are great they are free to create a new recipe to describe that
new method. What qualifies as 'great deviations' is a bit fuzzy, but that's
the idea.

it's a bit tricky to express it clearly!


Indeed. I drew a picture to make what I'm talking about (hopefully) more
clear. This includes only some of the core entities around making char. It
doesn't yet include any cultivation concepts, and it doesn't include an
Experiment entity. I can put that in later. This doesn't try to express all
the necessary fields, particular on charcoal analysis.

<
http://picasaweb.google.com/codesuidae/FilePile/photo?authkey=iddYZc2GDTQ#5114567166834245234
>

or

*http://tinyurl.com/yo7yze*

An Experiment is performed by a person, on a day, in a location and has a
pyrolysis event and log of what happened and what the persons observations,
and so an entity representing it would link to User, Location and
PyrolysisEvent and would include a date and Log field for the user to
include notes.

I'll stop now and see what you think.
Dave K
-- 
"Our ignorance is not so vast as our failure to use what we know." - M. King
Hubbert
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