Presumably, there is some standard lookup tables that both export and
import translator would consult in executing item lookups. I don't see any
information in the CIS documentation describing this sort of thing. In other
words, where are the standard, proprietary and library items definitions and how
do we get at them?
Answer to Q3
The ‘flavour files’ are provided with the CIS/2 documentation. The
flavour file is merely a collection of identifiers or references for
standardized items. All other data is found elsewhere - e.g. in national
standards or manufacturers catalogues. The use of the flavour file relies on the
fact that both the sending and receiving applications have access to the shape
data locally (e.g. in a native database). If this is not the case, then the data
must be 'passed by attribute value' rather than being 'passed by reference'. The
LPM allows the information to be passed by both attribute value and by
reference. If both applications involved in the data exchange have fully
populated native databases, then those databases may contain information that
lies beyond the LPM. In general, the 'flavour file' is used to exchange
information implicitly (via the reference) rather than explicitly (via the
attribute values).
Most of the information associated with the item_reference_standard already
exists in native form within applications. Any developer is at liberty to create
the equivalent neutral file for the data that is covered by the LPM.
Question 4
What type of products are 'proprietary items'?
Answer to Q4
Proprietary items are proprietary product items (such as cold rolled
sections) which comply to a manufacturer's catalogue. This would also include
'semi-standard' product items that comply to specifications agreed between a
consortium of manufacturers. Such items use an agreed human readable
'manufacturer's identifiers' published by the manufacturer as 'manufacturer's
lists'.
Question 5
Can you get the same section/shape data from a
‘flavour’ file rather than relying upon the convention included in CIS/2?
Answer to Q5
The flavour file is merely a collection of identifiers or
references for standardized items. The shape data (and all other data) is found elsewhere
- e.g. in national standards or manufacturers catalogues. The use of the flavour file
relies on the fact that both the sending and receiving applications have access to the
shape data locally (e.g. in a native database). If this is not the case, then the data
must be 'passed by attribute value' rather than being 'passed by reference'. The LPM
allows the information to be passed by both attribute value and by reference. If both
applications involved in the data exchange have fully populated native databases, then
those databases may contain information that lies beyond the LPM. In general, the
'flavour
file' is used to exchange information implicitly (via the reference) rather than
explicitly (via the attribute values).
Question 6
a.) There are a few section shapes which are standard but not in the UK
flavour currently including parallel flanged channels, asymmetric beams and
standard flats - these would be very useful additions.
b.) There are a number of sections which could be added - eg large UBs
(deep sections) many RHS, CHS etc which although not in the standards you
reference are rolled by Corus
c.) There are a number of other flavours we would be interested in seeing
present in the CIS - they include Japanese (our source are the JIS standards),
Canadian (available as disk based from the CISC) and Malaysian (available from
Perwaja).
d.) In the middle east and Asia pacific there is a tendency to use
whatever steel is available and if the CIS are going to be useful in that
region, all these need to be in there.
Answer to Q6
It should be noted that although the concept of a flavour is captured
and documented in CIS/2, the "Flavour Files" are NOT part of
the CIS/2 standard. The reason is simple - and you've already pointed it
out - there will be a demand for more and more of these files as CIS/2
conformant software is distributed around the world. The decision was
made early in the development of CIS/2 to allow for future expansion -
particularly of flavours. Thus, the flavour files distributed with the
CIS are just a start. However, we do not intend to "correct"
these files, we would rather have new ones created - and this is where
you come in. A "Flavour File" is just a CIS/2 file containing
a list of "standard references". The format of the reference (item_reference.ref)
is simply a STRING - so they could be more consistent.
I would not expect every application to support every standard item
of every flavour - thus a number of subsets are likely to emerge.
(Appropriate warnings should be incorporated in the translator's
documentation.) Any software vendor is at liberty to create a "Flavour
File". Of course, for maximum benefit, any flavour file should be
shared (and agreed by) the CIS User Group. The best place to hold these
files would be on the CIS/2 web site. The same argument applies to
proprietary items.
Question 7
I am using ST-Developer to generate my p21 and log files. Whenever I search a
flavor file for a match, I get warnings about tabs in the file. Are you familiar
with this problem?
Answer to Q7
I've come across these warnings before - they are harmless as far as
I know. I've not found a way of suppressing them - STEP Tools Inc. might
be able to help.
Question 8
CIS supports passing materials by flavour using 'item_reference_assigned' to map 'structural_frame_items'
to an 'item_reference_standard'.
Is this the way a flavour specified by grade
only, such as “ASTM_A36” can be mapped to a more common description
such as “Carbon Steel”, “A36” ?
Answer to Q8
Yes. From the CIS/2 download
page, it can be seen that grade A36 Carbon Steel is represented by
the following instances representing the standard reference:
/* Carbon Structural Steel 1994) */
#309011 = ITEM_REF_SOURCE_STANDARD ('ASTM', 'ASTM_A36', 1994, $);
#31440002 = ITEM_REFERENCE_STANDARD ('GRADE36',
#309011);
#285001 = GROUP ('American Standard Identifiers', 'List of Standard Identifiers to ASTM Standards');
#254004 = FLAVOUR (#285001, (#31440001, #31440002, ... #31440017));
To
assign this to a material use the 'item_reference_assigned'
entity.
#3051 = MATERIAL (123, 'A36',
'Carbon Steel')
#3311
= ITEM_REFERENCE_ASSIGNED (#31440002, #3051);
