Subject | RE: [firebird-support] Database design comments |
---|---|
Author | Luis Carlos Junges |
Post date | 2008-06-12T03:13:48Z |
Hi Leyne,
Yah. you are right, now i saw that NTFS accept 16TB files.
Doing the backup and restore Using full page,the size is 42 MB. Really good when the size decrease.
I would like to know you approach. I did not understand it quite well. You was proposing divide brushes by properties?
The similarity is based on 30(could be more) different technical construction properties like
* Material (7 classification)
* Hole type (3 different holes)
* shoulder type (3)
* chamfer type
* insulation type
* terminal type
* shape
So, when comparing brush 1 with brush2, the first one can have a shape and the second one a different shape. So the similarity will be zero. There is a set of pre-defined values that must match in order to have a minimum level of similarity (shape,application, both with or without shunt) . After this minimal set is reached, others comparisons will be performed and the result will be a percentage stored in column similarity at the table described.
"Leyne, Sean" <Sean@...> escreveu:
For example to find all brushes which are identical to each other (in 1
dimension), it would be very easy get the list of distinct values and
then build a result which list the brushes which match or lists
resulting brush-pairs.
Could you please explain the types of analysis which would be required.
--
Can you explain how similarity is determined/calculated?
Sean
---
Luís Carlos Dill Junges ©
"A realidade de cada lugar e de cada época é uma alucinação coletiva."
Bloom, Howard
---------------------------------
Abra sua conta no Yahoo! Mail, o único sem limite de espaço para armazenamento!
[Non-text portions of this message have been removed]
Yah. you are right, now i saw that NTFS accept 16TB files.
Doing the backup and restore Using full page,the size is 42 MB. Really good when the size decrease.
I would like to know you approach. I did not understand it quite well. You was proposing divide brushes by properties?
The similarity is based on 30(could be more) different technical construction properties like
* Material (7 classification)
* Hole type (3 different holes)
* shoulder type (3)
* chamfer type
* insulation type
* terminal type
* shape
So, when comparing brush 1 with brush2, the first one can have a shape and the second one a different shape. So the similarity will be zero. There is a set of pre-defined values that must match in order to have a minimum level of similarity (shape,application, both with or without shunt) . After this minimal set is reached, others comparisons will be performed and the result will be a percentage stored in column similarity at the table described.
"Leyne, Sean" <Sean@...> escreveu:
> I am building a system that will be able to compare electrical brushesI don't think I agree with your approach/reasoning.
> (graphite electrical brush).
> Basically the comparison will give the level of similarity and also
> highlight the differences between two brushes.
>
> The main problem is the quantity of brushes; i am talking about 500000
> brushes. So, i have to make 125 billions of comparisons (combinatory
> analysis C500000,2) in order to know the level of similarity among
> brushes.
For example to find all brushes which are identical to each other (in 1
dimension), it would be very easy get the list of distinct values and
then build a result which list the brushes which match or lists
resulting brush-pairs.
Could you please explain the types of analysis which would be required.
> * I have to store a reference for the two brushes and also the levelof
> similarity. I create a table like this|----------------------------------------------------------
>
> |brush1(integer) | brush2(integer) | similarity (smallint) |
>
--
> ----------|Is similarity determined/calculated using one or multiple factors?
> | 500000 | 34999 | 98
> |
> | 365 | 34999 | 99
> |
> | 1000 | 349 | 56
> |
> | 1000 | 365 | 75
> |
Can you explain how similarity is determined/calculated?
Sean
---
Luís Carlos Dill Junges ©
"A realidade de cada lugar e de cada época é uma alucinação coletiva."
Bloom, Howard
---------------------------------
Abra sua conta no Yahoo! Mail, o único sem limite de espaço para armazenamento!
[Non-text portions of this message have been removed]