nulling Surfs.Up.DVDRip.XviD-DiAMOND.[wnet.co.il].avi
Amos Batit
Jim Bretz
> i have question regarding the NULL process, but before i ask my question,
> can i get simple explanation about what happens "in the back door" of this
> process?
I'm going to start from the discription in the help file:
IADS offers two types of nulling capability, aircraft and weapon bay. The
user sets up and initializes what parameters are to be nulled in the
Configuration File, Parameter Defaults Table. The operator is required to
start nulls. Nulls are derived using approximately 15 seconds of real time
data, therefore once applied, they take about a minute before the user will
see the data adjust itself. This process may take longer depending on the
number of parameters being used in the current test. The user will see their
workstation pause momentarily and then the nulled data will start to be
displayed to them.
Ok, let me fill in here a little:
1) Parameters are chosen to be nulled by putting them in one of two nulling
"groups" from within the client. You can put a parmeter into a specific
nulling group by setting the "NullGroup" column in the ParameterDefaults
table (PD table) via the ConfigTool. By assigning a parameter to a group,
you can null them at separate times during your test. Unfortunately, we only
have two groups at this point, but we're going to expand this to unlimited
groups eventually.
2) Set the parameter's "NullCorrection" column to "yes" in the PD table.
3) Set the parameter's "NullBaseline" column to the expected value of the
parameter. Someone more knowledgeble than I will have to explain this in
detail ;)
4) Once the nulling group and bull baseline are defined... and null
correction is enabled for all your desired parameters in the PD table, you
can start the actual nulling process via the "Ops Console". In the Ops
Console application, select the "Modify CDS state" button on the toolbar,
then select Start on either one of the nulling groups defined.
5) After the Start button is pressed, the CDS averages (applies a
mathematical average) for 15 seconds (settable) on all the parameters that
belong to the nulling group started.
6) Once this average is complete, the CDS updates the "NullAverage" column
in the ParameterDefaults table (PD table) with these calculated values for
each parameter that's been nulled. It also updates the NullBias column via
the following equation:
NullBias = NullBaseline - NullAverage
7) When the client receives the PD table updates, it reads the NullBias for
every updated parameter and applies that offset to the data (post
processing). Let me emphasize here that it's doesn't modify the original
data, it simply applies this offset after it recieves the data (much like a
filter or sign change). At this point you should see the parameters "shift"
on the display visually to correspond to the new nulling values.
That's nulling in a nutshell. Step 6 is kinda the "behind the scenes" info
you wanted, but as you can see there's really nothing complex or exciting ;)
Jim
Amos Batit
Mike Burt
You can create a new derived parameter where the equation is just the
name of the original parameter and then set the NullCorrection field
in the ParameterDefaults table to "No"...this should give you the non-
nulled version of the parameter.
Jim Bretz
> so the process is much what i familiar with.
> next step of the question(it becomes more exiting:) )
> if the FTE says that the values appear to be suspicious.
> how can i reset the values to there original values of the parameters, so
> the FTE can see them in his displays?
>(From Mike)
Or just simply go through and change all of the original parameter's
NullCorrection field/column in the PD table to "No", save, and the client's
displays should return to their normal "un-nulled" value.
Jim
Jim Bretz
> NullCorrection field/column in the PD table to "No", save, and the
> client's
> displays should return to their normal "un-nulled" value.
Or "re-null"... i.e. repeat the nulling process.
Mike's technique will allow you to show the nulled and unulled values side
by side... so that's a good option there... but if you want to undo all of
the nulls, just set them all to "No" (or select ones) in the PD table from
any client in the room, save, and after the save everyone's parameters will
back to their original values (non-nulled).
There are other options, but that's probably the quickest,
Jim
Amos Batit
and click the "restart Null" buton?
Mike Burt
> 2) Set the parameter's "NullCorrection" column to "yes" in the PD table.
calculate null bias values...null biases will be calculated on entries
that have the appropriate NullGroup field set...regardless of the
NullCorrection column setting...
The bias will just not be applied to the data if NullCorrrection is
set to "No"...
Jim Bretz
Yes, thanx Mike for the distinction. "No" just means that the clients won't
use the null correction that's present in the PD table. So in other words,
you can calculate Nulls and apply them whenever you want (or never). The two
operations are disconnected.
> mike, after the parameters go back to the original values, i need to chang
> back the NullCorrection field/column in the PD table to "yes",
> and click the "restart Null" buton?
(It's Jim BTW... Mike can correct me if need be)
Nope... If you want to redo the nulls (i.e. recalculate the average because
the user's didn't like them), simply press the "start" button again from the
OpsConsole. You don't need to change anything in the PD table.
But, if don't want the clients to use the calculated nulls, then set them to
"No". Sorry, if I confused you...
> will the displays gets the last new Null values?
Yes, after you perform the null operation again (Start button via the
OpsConsole), the displays will get the new null values.
> is there any simple way?if i have many parameters in the Null list, it
> will take some time...
I'm thinking that you simply wanted to just "perform the nulls again". If
that's true, you don't need to change anything in the PD table by hand. Just
start the nulling operation again (Start via OpsConsole).
If you want a quick way to turn on/off all of the null corrections for all
of the clients in the room, we don't have that right now, sorry..... but, we
could build a VB script that would do it for you. That wouldn't be too
difficult.
Let me know if that confused you enough ;)
Jim
Mike Burt
> back the NullCorrection field/column in the PD table to "yes",
> and click the "restart Null" buton?
bias to the data all you need to change is the NullCorrection field in
the ParameterDefaults table...you do not need to restart nulling...
> will the displays gets the last new Null values?
displays as soon as the recalculated values are propagated to the IADS
client (i.e. null bias fields are updated in the ParameterDefaults
table)...
> is there any simple way?if i have many parameters in the Null list, it will
> take some time...
has deemed "suspicious" while trying to figure out what is going on...
Amos Batit
James Bretz
> first thank you all for the all the responses.
> i think I've miss match my case, so I'll try to make it more correct to my
> case.
Ok, thanx... Ya, it's always good to know the exact issue ;)
> the FTE asked the pilot to start Nulling process, and in the same time
> asked
> me to start nulling in the opconsole.
Serious question. What is the pilot doing when the FTE asks them to "start
the nulling process"? Is there some kind of on board nulling of parameters,
or is the pilot just performing the "nulling maneuver" (i.e. hold plane at
constant speed, altitude, etc). If there is any on board nulling, and the
pilot is nulling any of the same parameters as Iads then you may be "double
nulling" and you'll get the wrong answers. Understand?
> after the Nulling process ends, he looks at the results and decide that he
> want to repeat the Nulling again,BUT before the restart of the Nulling he
> wants to see the original values before the first Nulling.
> how can i show him the original values?
> the only way i know, is (unfortunately) to restart all the IADS and start
> from blank :(
Currently, there's no "button" to turn on/off nulling for the client, so
we'd have to work around that issue:
1) Do what Mike suggested. Create a select few derived parameter with the
nulling *always* off and put them on a "checkout nulling display" (i.e. a
separate group of stripcharts or other displays on a tab or another
AnalysisWindow). The user can look at this group of displays during nulling
"checkout". Just create a number of derived parameters with the following
equation:
SetNullCorrection( Param, 0 ), Param
So, if you wanted to create new derived parameters for say 20 parameters
that had nulling always disabled/off:
ParamAWithNoNulling => SetNullCorrection( ParamA, 0 ), ParamA
ParamBWithNoNulling => SetNullCorrection( ParamB, 0 ), ParamB
...
ParamNWithNoNulling => SetNullCorrection( ParamN, 0 ), ParamN
Then you build up 20 stripcharts on a new AW, put ParamA in the first
stripchart, and also put ParamAWithNoNulling (hold ctrl key down with
dropping into StripChart)... Then repeat that process for the remaining 19
stripcharts. Now you will have a display that always shows the "non-nulled"
and also "nulled" parameters that is easy to compare. After the nulling
"checkout" is done, simply go back the original AW and continue the flight
test.
2) Create a VB script to modify the ParameterDefaults table and turn off all
nulling. If you have 6.0, you can execute the script using a "Button". So
you could have a "Turn off Nulling" and "Turn on Nulling" capability. Also,
you can limit the changes to that particular PC. The script interface allows
you to choose whether to save the changes to the server or just keep them
locally.... You could also just execute the script from a desktop shortcut
on the OpsConsole that would effect the entire room. Your choice.
3) Create a custom display (i.e. you're own button) to turn on/off nulling.
This technique would work in any version, but it would take some
programming. I could help or maybe we could find someone in the office who
can donate some time ;)
4) Wait until we implement something in a future release. That might be a
long wait because we're pretty busy right now ;)
Now that I'm thinking about it, I like option #1 because the user can see
*both* nulled and un-nulled together on the same StripChart. Next favorite
option is #3.
> another important thing - the archiving.
> what about the data in the archive?
> will it show the original values before the Nulling?(after the Nulling
> process...as shown in the first rows...)
Yes, always. Only the original, non edited, non filtered, non spike
detected, etc data is saved into the file. All the modifications are done as
"post processing" operations in a "just in time" fashion..... So this means
you can turn those features on/off at any time without effecting the
original data.
> what i expect to see, is the orig. values, the "after Null" value,reset to
> the orig value and in the end the new Nulling value. ( :( )
Ya, I understand.... and would see that exact behavior if you could turn the
nulling on/off with a button. Better yet, if you use method #1, you can see
both values on the same stripchart and compare them more easily.
> ohhh. i hope i wrote it right...
Yep, you did... I just hope I understood that correctly ;)
Jim
Amos Batit
4. moment of silence... that's it. no one says word on this issue. :)
James Bretz
> 2. i just noticed the headline of this mailing . what have i dun? how did
> i
> missed it ;)
> 3. how come no one noticed it (or did, but did not want to make an issue
> of
> it :) )
> 4. moment of silence... that's it. no one says word on this issue. :)
LOL! Hey, this is California. "Surfs up" is a good thing around here ;) And
how can Diamonds be bad? Also, XVID is a pretty good free codec.
Don't worry about it.. No problem,
Jim