UCDwordsRFM < IVOA

---++ A printable version ([[%ATTACHURL%/RFM-proposal.pdf][.pdf]]) of this page.
---

---+ RFM (Request for modification) of the List of UCD-words

AndreaPreiteMartinez
IVOA – Semantics WG

TN - 20060713



What follows is a list of proposed requests (*RFM*) to modify/add the present standard list of ucd-words: *The UCD1+ controlled vocabulary, Vers. 1.11 - IVOA Recommendation 31 December 2005*  (http://www.ivoa.net/Documents/latest/UCDlist.html ). 

The RFMs were collected over the past few month, from suggestions coming from various members of the IVOA community. 
The list has been presented at the UCD-session in Victoria, and corrected taking into account the discussions during the meeting within the WG and with the Theory IG. Other suggestions have been added to describe attributes used by some Data Models.

The list is open for discussion in accordance with the approved standard procedure: *Maintenance of the list of UCD words, Version 1.20 - IVOA Recommendation 28 May 2006* (http://www.ivoa.net/Documents/latest/UCDlistMaintenance.html ).

Due to web security problems, for the moment we discourage the usage of the web-based form for submitting RFMs. On the other hand we can consider the present list of RFMs as a collective effort of the community, not requiring a private personal answer (see par. 2.2 and 2.3 of the maintenance document). For the time being, all the RFMs and all the corresponding answers will be grouped together in the present public document. Other RFMs could be proposed during the discussion phase, so that we can consider this document as a temporary repository of all proposed RFMs. 


---++ *1. RFM (amendments/clarifications):* 

A generic request was presented for a richer semantic definition of ucd-words as part of the document itself or, alternatively, to include an explicit, and obvious, reference to a separate "usage" document with examples. %BR%
*Answer:* The original request concerned the description of the ucd-words in the time branch. A complete proposed revision of the time branch can be found in a TN at the end of this document.


---++ *2. RFM (deletions/replacements):*

Q | phys.atmol    | suppress without replacing %BR%
*A:* there is not such a quantity as “phys.atmol”, but the word could be used as a qualifier. The proposal is to replace it with: S | phys.atmol
---
Q | phys.at.qn.I    |   suppress, replacing with old Q | phys.at.qn %BR% 
*A:* ok
---
Q | phys.at.damping  |  suppress, replacing with new:%BR%
   Q | phys.damping     |Generic damping %BR%
*A:* ok
---

---++ *3. RFM (additions):*

S | comp    | Related to computational techniques, methods, etc.%BR%
*A:*
---
S | comp.sim   | Related to computational simulation%BR%
*A:*
---
S | comp.resource    | Computational resources used in simulation/data processing%BR%
*A:*
---
S | comp.smooth     | Related to smoothing of images or particle densities %BR%
*A:*
---
S | phys.cosmology    | Related to cosmology%BR%
*A:*
---
S | phys.virial     | Related to virial quantities (mass, radius, ..)%BR%
*A:*
---
Note:%BR%
Other “computational” and “cosmological” words were discussed in Victoria, also with the Theory IG. We need an input from them in order to revise/complete the list below:

S | comp.sim.nbody   | Nbody simulation%BR%
S | comp.sim.sph   | Smoothed Particle Hydrodynamics simulation%BR%
S | comp.sim.boxside    | Simulation box%BR%
S | comp.sim.gravsoft    | gravitational softening%BR%
S | comp.sim.particles    | simulation particles - for Nbody and SPH  simulations%BR%
S | comp.sim.snapshot    | output of a simulation box at a particular instant%BR%
S | comp.sim.grid    | simulation grid - for hydro simulations%BR%
Q | comp.resource.processors     | processors used%BR%
Q | comp.resource.memory       | total size of a data file%BR%
Q | phys.cosmology.omega          | matter/energy density of universe%BR%
Q | phys.cosmology.hubble          | hubble constant%BR%
Q | phys.cosmology.sigma8          | Normalisation of matter power-spectrum%BR%
S | phys.matter.dark   | dark matter tag%BR%
S | phys.matter.baryon   | baryonic matter tag%BR%
S | phys.DarkEnergy   | dark energy tag

---
S | obs.proposal      | Observation proposal%BR%
*A:*
---
Q | obs.proposal.cycle   | Proposal cycle%BR%
*A:*
---
P | meta.code.status   | Status code%BR%
*A:*
---
P | meta.id.PI   | Name of Principal Investigator%BR%
*A:*
---
P | meta.id.CoI   | Name of Co-Investigator%BR%
*A:*
---
Q | meta.email   | Curation/contact e-mail%BR%
*A:*
---

Examples:%BR%
meta.id;obs.proposal  |   name of the proposal%BR%
meta.code;obs.proposal   | proposal code%BR%
meta.code.status;obs   | status of an observation%BR%
meta.id.PI;obs   | PI of the observation%BR%
meta.id.CoI;obs.proposal   | Co-Investigator of the proposal%BR%

---
S | em.IR.FIR   | Far-Infrared%BR%
*A:*
---
S | em.IR.MIR   | Medium-Infrared%BR%
*A:*
---
S | em.IR.NIR   | Near-Infrared%BR%
*A:*
---
S | em.UV.FUV   | Far-UV%BR%
*A:* 
---
S | src.net   | indicating that a quantity (e.g. flux) is background subtracted rather than total%BR%
*A:*
---
S | phot.uncalib   | photometric uncalibrated measurement%BR%
*A:*
---
S | obs.calib.flat   | sky/dome flat observations%BR%
*A:*
---
S | src.calib   | Calibration source%BR%
*A:*
---
S | src.calib.guideStar   | Guide star%BR%
*A:*
---

Examples:%BR%
meta.id;src.calib;phot   | source used for photometric calibration%BR%
meta.id;src.calib;spectr   | source used for spectroscopic calibration%BR%
meta.id;src.calib;pos   | source used for positional/astrometric calibration%BR%

---
Q | phys.damping     |Generic damping  %BR%
*A:* see above par. 2. RFM
---
S | phys.particle.*   | Elementary particles (electron, proton, neutrino, etc.)%BR%
*A:* for the moment we only need the electron. 
---
To indicate the quantity    _flux density_   or   _flux per unit wl/fr/en/wn..._  there are three proposals:

(a) use always phot.flux.density; UCDs don’t care about units;

(b) add the new words:%BR%
phot.flux.perFreq   | Flux density (per unit frequency)%BR%
phot.flux.perWave   | Flux density (per unit wl)%BR%
phot.flux.perEnergy   | Flux density (per unit energy)%BR%
phot.flux.perWavenumber   | Flux density (per unit wn)%BR%
phot.flux.perDecade    ( nu*F_nu, lambda*F_lambda)%BR%

(c) use a composite UCD without need for new words:%BR% phot.flux;em.freq
---
weather   | new branch to address weather phenomena (at obs. sites)%BR%
*A:* there is already the word  obs.atmos  to indicate atmospheric phenomena
---
From DM-Lines :

Q | spect.line.strength      | Spectral line strength S%BR%
*A:*
---
Q | phys.atmol.sWeight.nuclear   | Statistical weight for nuclear spin states%BR%
*A:*
---
Q | phys.atmol.symmetry      | Type of nuclear spin symmetry%BR%
*A:*
---
Q | stat.probability      | Probability %BR%
*A:*
---
Q | phys.entropy      | Entropy%BR%
*A:*
---

From DM-Spectral:

Q | em.bin    | channel / instrumental spectral bin coordinate (wl, freq, energy)%BR%
*A:*
---
Q | em.binSize    | spectral bin size%BR%
*A:*
---
S | stat.filling   | filling factor (volume, time,..)%BR%
*A:*
---



---

---+ A proposed new UCD1+ time-branch

---++ A more consistent approach to the description of time-related quantities with UCDs.


AndreaPreiteMartinez, IVOA – Semantics WG

---+++ TN - 20060701




The *time* branch in the IVOA Rec v1.11 is the following:


| *SF* | *word* | *description* |
| Q | time                               | Time |
| Q | time.age                           | Age |
| Q | time.crossing                      | Crossing time |
| Q | time.epoch                         | Epoch, julian date |
| Q | time.equinox                       | Equinox |
| Q | time.event                         | Duration of an event or phenomenon |
| Q | time.event.end                     | End time of event or phenomenon |
| Q | time.event.start                   | Start time of event or phenomenon |
| Q | time.expo                        | Exposure on-time, duration |
| Q | time.expo.end                      | End time of exposure |
| Q | time.expo.start                  | Start time of exposure |
| Q | time.interval                      | Interval of time |
| Q | time.lifetime                      | Lifetime |
| Q | time.obs                           | Observation on-time, duration |
| Q | time.obs.end                      | End time of observation |
| Q | time.obs.start                     | Start time of observation |
| Q | time.period                        | Period |
| Q | time.phase                         | Phase |
| Q | time.relax                         | Relaxation time |
| Q | time.resolution                    | Time resolution |
| Q | time.scale                         | Timescale |

The request is to introduce a clearer separation between *instant* of time and *duration* in time.


The situation now is:

The words referring to *instants* of time are: %BR%
time.epoch %BR%
time.event.end %BR%
time.event.start %BR%
time.expo.end %BR%
time.expo.start %BR%
time.obs.end %BR%
time.obs.start

The words referring to a *duration* or an interval of time are:%BR%
time.event %BR%
time.expo %BR%
time.obs %BR%
time.interval %BR%
(but in this last case we mean a time-bin, or the time elapsed between two events, not the duration of an event. We need to make the description clearer)

In addition we have some other rather specific time-words that we leave untouched. 


---++ Proposal: 

we keep the atoms indicating instants:%BR%
epoch, %BR%
start, %BR%
end  %BR%    
(although a strict hierarchization should give: 
epoch, epoch.start, epoch.end !!)

and we introduce a new atom  *duration*  to indicates duration, interval of time during which a generic event/observation/phenomenon is taking place.

We keep the atoms indicating what instants and duration we are referring to:%BR%
obs (observation)%BR%
expo  (exposure)%BR%
event  (generic event, pleonastic!)%BR%
and introduce a new atom 
*sequence* (to indicate a correlated sequence of observations)

One possible combination of atoms is:

*time*,   at level 1%BR%
*instants/duration*   at level 2%BR%
*type of event described*   at level 3


Examples:

| *Description* | *v1.11* | *new version* |
| time/date of observation | time.epoch | time.epoch.obs |
|  or:  | time.epoch;obs | time.epoch;obs |
| observing time | time.obs | time.duration.obs |
|   or:   | time;obs | time.duration;obs |
| exposure time | time.expo | time.duration.expo |
| start time of a sequence | time.obs.start | time.start.sequence |

In addition, we propose three more atoms to describe creation, publication/release and processing times for data, files, catalogues, etc.


The new proposed *time* branch is illustrated in the following Table. New ucd-words and new descriptions are in italic. Old (v1.11) ucd-words that are not repeated in column *new version* are suppressed.



---+++ Table 1.  The proposed new **time** branch in UCD1+.

| *SF* | *word in v1.11* | *new version* | *description* |
|Q|time|time|__Generic quantity in units of time or date__|
|Q|time.age|time.age|Age|
|Q||__time.creation__|__Creation time/date (of dataset, file, catalogue,...)__|
|Q|time.crossing|time.crossing   |Crossing time|
|Q||__time.duration__|__Interval of time describing the duration of a generic event or phenomenon__|
|Q||__time.duration.event__|__Interval of time describing the duration of an event (pleonastic, see above)__|
|Q||__time.duration.expo__|__Interval of time describing the duration of an exposure, on-time__|
|Q||__time.duration.sequence__|__Interval of time describing the duration of a correlated sequence of observations/events__|
|Q||__time.duration.obs__|__Interval of time describing the duration of an observation__|
|||time.duration;obs|(Alternative form)|
|Q||_time.end_|_End time/date of generic event_|
|Q||_time.end.event_|_End time/date of event (pleonastic, see above)_|
|Q||_time.end.expo_|_End time/date of exposure_|
|Q||_time.end.sequence_|_End time/date of a correlated sequence of observations/events_|
|Q||_time.end.obs_|_End time of observation_|
|||time.end;obs |(Alternative form)|
|Q|time.epoch|time.epoch|Instant of time related to a generic event (epoch, date, Julian date, time stamp/tag,...)|
|Q||_time.epoch.event_|_Instant of time/date related to an event (pleonastic, see above)_|
|Q||_time.epoch.expo_|_Instant of time/date related to an exposure_|
|Q||_time.epoch.sequence_|_Instant of time/date related to a sequence of observations/events_|
|Q||_time.epoch.obs_|_Instant of time/date related to an observation_|
|||time.epoch;obs|(Alternative form)|
|Q|time.equinox|time.equinox|Equinox|
|Q|time.event||Duration of an event or phenomenon|
|Q|time.event.end||End time of event or phenomenon|
|Q|time.event.start||Start time of event or phenomenon|
|Q|time.expo||Exposure on-time, duration|
|Q|time.expo.end||End time of exposure|
|Q|time.expo.start||Start time of exposure|
|Q|time.interval|time.interval|_Time-bin, or the time elapsed between two events, not the duration of an event_|
|Q|time.lifetime|time.lifetime|Lifetime|
|Q|time.obs||Observation on-time, duration|
|Q|time.obs.end||End time of observation|
|Q|time.obs.start||Start time of observation|
|Q|time.period|time.period|_Period, interval of time between the recurrence of phases in a periodic phenomenon_|
|Q|time.phase|time.phase|_Phase, position within a period_|
|Q||_time.processing_|_A time/date associated with the processing of data_|
|Q|time.relax|time.relax|Relaxation time|
|Q||_time.release_|_The time/date data is available to the public_|
|Q|time.resolution|time.resolution|Time resolution|
|Q|time.scale|time.scale|Timescale|
|Q||_time.start_|_Start time/date of generic event_|
|Q||_time.start.event_|_Start time/date of event (pleonastic, see above)_|
|Q||_time.start.expo_|_Start time/date of exposure_|
|Q||_time.start.sequence_|_Start time/date of a correlated sequence of observations/events_|
|Q||_time.start.obs_|_Start time of observation_|
|||time.start;obs|(Alternative form)|
         



In Table 2 we list the suppressed ucd-words, and the new words replacing them.

---+++ Table 2. Proposed suppressions / replacements


|*SF*|*suppressed*|*replacement*|*description*|
|Q|time.event |time.duration[.event] |Duration of an event or phenomenon|
|Q|time.event.end  |time.end[.event] |End time of event or phenomenon|
|Q|time.event.start |time.start[.event] |Start time of event or phenomenon|
|Q|time.expo |time.duration.expo |Exposure on-time, duration|
|Q|time.expo.end |time.end.expo |End time of exposure|
|Q|time.expo.start |time.start.expo |Start time of exposure|
|Q|time.obs |time.duration.obs |Observation on-time, duration|
|Q|time.obs.end  |time.end.obs |End time of observation|
|Q|time.obs.start |time.start.obs |Start time of observation|
         







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This topic: IVOA > UCDwordsRFM
Topic revision: r7 - 2006-07-17 - AndreaPreiteMartinez