Academic Image Cooperative
Data Model Entity Definitions

SortOrder[3.1]

DIAGRAM_NAME[ Physical Properties ]
Entity_Name[ WorkItem ]
Entity Type
Independent_Entity[ x] or
Dependent_Entity[ ] or
Associative_Entity[ ] or
Subset_Entity[ ]
Entity_Description[ -

WorkItem is the main record for a cataloged work of art, its Key field, WorkItemID, identifies the work. Here in the Physical Properties diagram, it is represented summarily in order to show the relationship between the Physical Properties entities and the rest of the database.

One-to-many relationship. One WorkItem record may link to zero, one or many records in the Materials, Technique or Measurements entities.

In the Physical Property entities the editor can list multiple occurrences for Materials, Techniques or Dimensions. Typically such relationships are difficult to display in an economical and concise manner as required by the occasional researcher, but they are important for research purposes. In addition, certain constructs are combining more than a single property are difficult to present. A painting may be listed as composed of wood frame, canvass, gesso, oil medium, copper nails and varnish, but all the user cares about is "oil on canvass." For these situations the WorkItem entity provides "Display Fields" in which the common terms for materials, techniques, and brief measurement notes can be entered. For these fields there should be an authorized list of entry values -- values that may not correspond with those in the authority files to which the multi-valued links refer. For example, "multi-media" may be a value for the display field but not for the authority table for Materials.

In the Physical Properties diagram, WorkItem is linked to three dependent entities:

1)Materials. One-to-many relationship. One WorkItem record to zero, one or many Materials records.
2)Technique. One-to-many relationship. One WorkItem record to zero, one or many Technique records.
3)Measurements. One-to-many relationship. One WorkItem record to zero, one or Many Measurement records.

RULES:

A) There is a many-to-many relationship between the WorkItem entity and the MaterialAuthority entity. One record in MaterialAuthority may link to many records in WorkItem. One record in WorkItem may link to Many records in MaterialAuthority.

The database must prevent duplicate many-to-many links between WorkItem and MaterialAuthority. If a record in MaterialAuthority is to be deleted and it is linked to one or more records (through Materials) to WorkItem, the editor must be informed that a linked records is being edited or deleted.

B) There is a many-to-many relationship between the WorkItem entity and the TechniqueAuthority entity. One record in TechniqueAuthority may link to many records in WorkItem. One record in WorkItem may link to Many records in TechniqueAuthority.

The database must prevent duplicate many-to-many links between WorkItem and TechniqueAuthority. If a record in TechniqueAuthority is to be deleted and it is linked to one or more records (through Technique) to WorkItem, the editor must be informed that a linked records is being edited or deleted.

C) There is a many-to-many relationship between the WorkItem entity and the WhatIsMeasuredAuthority entity and the UnitOfMeasureAuthority. One record in WhatIsMeasuredAuthority or UnitOfMeasureAuthority may link to many records in WorkItem. One record in WorkItem may link to Many records in WhatIsMeasuredAuthority or UnitOfMeasureAuthority.

The database must prevent duplicate many-to-many links between WorkItem and WhatIsMeasuredAuthority or UnitOfMeasureAuthority. If a record in WhatIsMeasuredAuthority or UnitOfMeasureAuthority is to be deleted and it is linked to one or more records (through Measurements) to WorkItem, the editor must be informed that a linked records is being edited or deleted.

For Display Categories: These fields are used to identify those values that are commonly used to identify the work cataloged. They should be taken from the linking files (when available). The linking files (except for Measurement) contain boolean fields that indicate when a value conforms to this criteria. The boolean field in these cases must be programmed so that in the set of values attached to WorkItem only one boolean value is to be allowed to be "True." Further, in any summary display using the display fields, when more than a single record is attached to the item, an indicator should show how these items should be retrieved. I would prefer a button to be placed next to such values which, when pressed would open a window listing each related value and that further action will open additional attached records.

FIELDS:

WorkItemID
WorkItemID is the key field for WorkItem. The value of WorkItem is assigned serially and corresponds to the values defining the WorkId field in the temporary Concordance-entity WORK table. Beginning at some value superior to the last assigned value in the Work table.

MaterialMediaDisplay
This field corresponds to the VRA Core Categories Ver 2.0 number W4. Material. But it differs from the VRA specifications in that it is a single value and is not repeatable.

Its value answers the question "What is the work made of?" but selects those materials generally considered most significant to the work, leaving out lesser substances. Further, the value in this field follow common conventions: "oil on canvass," "panel." Guidelines for the use of this field must be established. Such guidelines, it is suggested, serve the general user and avoid specificity. Keep specific references to kinds of materials limited to the multi-valued mechanism that is served by the Materials entity. Consistence is important, however, and an internal set of authorized terms may be kept on-line or in a separate table (not shown).

Editors should be allowed to select a value for this field by executing a query for a string and be presented with all values that contain that string. They may then choose a single value for that list. In addition, to ease editing, the editor should be able to request that the last entered value be repeated. A third mechanism for selecting values should permit the user to begin typing, and as new characters appear the list of possible values grows smaller until the editor hits enter or chooses one of the few remaining. This technique should be used for editing wherever values have already been recorded in authority files or in fields where limited values are allowed.

The AAT has an extensive materials hierarchy and other guides such as the Revised Nomenclature (Blackaby and Chenhall) also collects suitable terms.

TechniqueDisplay
This field corresponds to the VRA Core Categories Ver 2.0 number W5. Technique. It answers the question: "How was the work made or altered." The same may be said of the use of this field that was said of the MaterialMediaDisplay field, above. However, often the technique used is obvious and need not be displayed, is so technical that it is important to know only for certain uses or is not germane to the typical use of the work of art. Use of the terminology of techniques (sometimes called process), therefore, because this is a display field, should be restricted to those occasions when its use is obviously necessary.

As for the TechniqueDisplay field, as in the MaterialMediaDisplay field, an authority file (built and made accessible along the lines described above) should be built on the field. This may be an internal list or a list made available through a linked file (not shown in the diagram).

note:

This field is included in addition to the a multi-valued structure (Technique and TechniqueAuthority) that permits individual techniques taken from an authority file to be linked in a many-to-many relationship to the WorkItem file. Use this device for precise assignments and identifications of techniques.

In almost all cases that use authority files, it might be prudent to limit the values in these files to those terms to which links exist. Or, perhaps when searching an authority file those terms for which links exist should be identified in some manner -- such as showing them in red or by placing an asterisk next to them. The reason for this is clear: If a researcher is using, say, the MaterialsAuthority file to find works made of a certain substance, it would be useful to know which values will and which values won't produce a hit.

MeasurementsDisplay
Again, because the recording of significant measurements is so complex a task in databases, the WorkItem entity contains a text field in which to represent key measurements that serve to give the user an idea of the size or extent of the work that has been identified. The content of the MeasurementsDisplay field should be similar to the kind of size information typically provided in image captions in textbooks.

The Measurement field corresponds to the VRA Core Ver 2.0 category number W3. The text entered in this field answers the question "What are the proportions or size of the work?" In the VRA Core Guidelines this field is designated as repeatable -- in order to record multiple measurements and measurement data. MeasurementsDisplay is not repeatable; rather, a separate unit -- repeatable records in a linked file has been designed to handle the requirement of repeatability. But it cannot properly display this information in a formatted manner.

For usage information consult the VRA Core Categories General Guidelines.

A note on dimensions. When dimensions derive from measurements it is generally considered inappropriate to convert measurements from one system to another. The reason for this is that the system of measurement and the degree of precision in a measurement presumes a specific degree of approximation. For example 5 1/8 inches is presumed to be accurate (for instance) + or - 1/16 of an inch, while 5 3/16 inches might be presumed to be accurate + or - 1/32 of an inch -- half the smallest unit specified. When converting these measurements to the metric system, assuming 2.54 cm per inch, the metric equivalent results in a number which appears to be more accurate than the original measurement. Because information received into the AIC database comes indirectly, mostly from published sources, it is impossible (unlike for museums) to remeasure or to validate measurements obtained.

We will revisit the issue of recording dimensions when we discuss the entity called Measurements.

]
Entity_Connection_One-Name[ ]
Entity_Connection_One_Cardinality[ ] 1)1:1, 2)1:M, 3)M:M
Entity_Connection_One_Direction[ ] Parent / Child

Manditory[ ] or
Optional[ ]

Academic Image Cooperative
Data Model Entity Definitions

SortOrder[3.2]

DIAGRAM_NAME[ Physical Properties]
Entity_Name[ Materials ]
Entity Type
Independent_Entity[ ] or
Dependent_Entity[ ] or
Associative_Entity[ x ] or
Subset_Entity[ ]
Entity_Description[ The Materials Entity is a link (associative) file used to connect values in the MaterialAuthority entity to the WorkItem entity. There is a one-to-many relation between WorkItem and Materials: One record in WorkItem may have zero, one or many records in Materials. It is not mandatory to have Materials cataloged in the Materials entity since there is a MaterialMediaDisplay field available in the WorkItem entity. However it is recommended.

The Materials entity has a one-to-many relationship to the MaterialAuthority entity. One record in MaterialAuthority may be linked to zero, one or many records in the entity Materials.

One record in the Materials entity connects one MaterialTerm in the MaterialAuthority to one item in the WorkItem entity.

RULES:

Care must be taken that duplicate connections between a WorkItem and a MaterialTerm do not exist. Such duplicate links should be prohibited.

If there is an attempt to edit or delete a linked term in the MaterialAuthority entity, the user/editor should be made aware of the link and be warned before deleting or editing it.

Materials entity records that are not linked to both a MaterialAuthority record and a WorkItem record should not be allowed to exist. It might be possible to require that both The MaterialAuthority record and the WorkItem record that form the ends of the link precede in existence the record in the Materials entity. But the Materials entity record should be allowed to exist in transient memory during the process of link creation, but should be saveable only when the links are fashioned.

For example, a procedure: A WorkItem record has been created and is current. The editor attempts to establish a link to a specific material, say the material is nickel silver which does not exist in the MateiralAuthority entity. From the Materials entity the user should be able to query the MateiralAuthority entity.

A query should allow 1) a search by string, resulting in a series of records matching the string, 2) an alphabetical narrowing routine in which the user begins typing the term needed and the list of possible matches decrease with each letter, and 3) the ability to recall the last link and/or the history of recent linking terms.

The term "nickel silver" is not present. When not present the user should be given an opportunity 1) to consult the AAT or other on-line resource and 2)to add the term into the MaterialAuthority.

The MaterialAuthority provides for non-preferred terms and uses a recursive relationship to get to a preferred term from a non-preferred one.

There are a number of similar procedures and links to be established in the database, and this formula or an adaptation of it should be used uniformly for this linking procedure.

The builder of recursive relationships should be prevented from creating circular structures in which parent records are made children of their own children or descendants.

FIELDS:

MaterialsID
MaterialsID is the Key field for the Materials entity. Each value is unique, it is numeric and is assigned sequentially.

WorkItemID
WorkItemID is the foreign key for the relation to the WorkItem entity.

MatForDisplay
This field is a boolean field that indicates that the term selected is important enough to be used in a display of materials for the linked object. "Y" indicates that it can be used, "N" indicates that it cannot be used.

MaterialAuthorityID
This is the Foreign Key field that links the Material Entity to the Material Authority.

PROVISIONAL FIELD:

MaterialsNote
This would be a note field in which to record comments on the nature of the link between object and the MaterialAuthority file. For instance this field may be used to explain where or how the material is used and, perhaps, in what condition it is in. To employ this field it would mean that once a Materials record is linked to a record in the MaterialAuthority entity it could not be reassigned to a different material.

]
Entity_Connection_One-Name[ ]
Entity_Connection_One_Cardinality[ ] 1)1:1, 2)1:M, 3)M:M
Entity_Connection_One_Direction[ ] Parent / Child

Manditory[ ] or
Optional[ ]

Academic Image Cooperative
Data Model Entity Definitions

SortOrder[3.3]

DIAGRAM_NAME[ Physical Properties ]
Entity_Name[ MaterialAuthority ]
Entity Type
Independent_Entity[ x ] or
Dependent_Entity[ ] or
Associative_Entity[ ] or
Subset_Entity[ ]
Entity_Description[ The MaterialAuthority entity is an authority file composed of terms taken from the Art and Architecture Thesaurus and from other sources that are to be used to indicate which materials are used in a particular work of art.

It is linked to the associative entity Materials in a one-to-many relation. One record in the MaterialAuthority entity may link to zero, one or many records in the Materials entity.

See discussion in the Materials entity description for the rules that govern the making and unmaking of relations between MaterialAuthority and WorkItem.

The MaterialAuthority entity contains a recursive structure that permits finding a "preferred term" associated with a "non-preferred term"

Data for the MaterialAuthority may be derived (preferably)from established authority sources such as the materials hierarchy in the Art and Architecture Thesaurus or from Revised Nomenclature. But it can also support local terms or terms preferred by the AIC editors.

Query procedure. See also note below under the field: MaterialAuthorityID/1. When a user queries the MaterialTerm in the MaterialAuthority entity he should be aided by several tools: 1) if a search by string is initiated the results should show a list of MaterialTerm values that correspond to the searched string. In such a case the user should be allowed to choose from among (one or more) values to use to continue the query. or 2) if a user begins to type in a value for MaterialTerm, a query list of potential hits should be displayed. The list gets shorter in conjunction with the number of characters entered. 3) The reader should have available a history list of terms used in the current session. This procedure should be available for most situations where queries are allowed.

Note For the Prototype development.
It is unlikely that much effort will be made during AIC prototype development to fill in the associative files in the Physical Properties section (W.4 Materials, W.5. Technique and W.3. Measurements) because narrative (display) substitutes for these fields exist in the WorkItem entity. Time may be saved by not developing programming for these sections until later.

Rules:
The builder of recursive relationships should be prevented from creating circular structures in which parent records are made children of their own children or descendants.

FIELDS:

MaterialAuthorityID
This is the key field for the MaterialAuthority entity. It is unique and is added to sequentially. Deleted records cancel the value in the key field.

MaterialClassification
This is a one-level classification scheme that may be used to arrange the terms being collected. The classification is to be developed by the AIC cataloger.

MaterialTerm
This field contains the term that identifies (one of) the material(s) out of which the object in WorkItem is made. It should be taken from an authorized list such as the AAT whenever possible.

Values in this field are required and are indexed for uniqueness.

MaterialSource
This field identifies the name of the terminology source from which the term in MaterialTerm has been taken. There should be an authority list for these sources. In addition, these sources should be identified in the bibliography file. [Not implemented in this scheme is a link from the MaterialAuthority entity to the bibliography file.]

MaterialSourceCode
Some terminology sources identify their thesaurus entries by code, often numeric. This field provides the editor opportunity to record the appropriate code for the term in MaterialTerm.

MaterialTermPreferred
This Boolean field indicates whether the term that appears in MaterialTerm is a preferred term or a non-preferred term. If the field is "Y" or "True" then it is a preferred term and can be used. If it is not preferred (i.e. the field is "N" or "False") then the term is not legitimate for this database (but should be available for queries). In that case the field entitled MaterialPreferredTerm contain the MaterialAuthorityID of the record that is preferred. See below.

MaterialPreferredTermID
See above. If MaterialTermPreferred is "False" or "N" then this field contains the record number (MaterialAuthorityID) of the record that contains the preferred term. The editor is given the opportunity to query this record number and attach the Materials entity record to the MaterialAuthority record corresponding to the preferred term. But see below.

MaterialAuthorityID/1
This field was created by VISIO to indicate the recursive arrangement between records that hold non-preferred terms. It is a foreign key to the Primary Key MaterialAuthorityID.

I expect that this field serves the purpose I had in mind by defining MaterialPreferredTerm (above). In such case MaterialPreferredTerm should be deleted.

This contains the value of the primary key field of the preferred term when the MaterialTerm field is marked as "non-preferred." Having non-preferred terms in the database increases the likelihood that user queries will be successful.

Queries: When a user queries for a non-preferred term, the search procedure should follow the link in MaterialAuthorityID/1 and present the preferred term to use. The user should be informed that he has hit a non-preferred term.

]
Entity_Connection_One-Name[ ]
Entity_Connection_One_Cardinality[ ] 1)1:1, 2)1:M, 3)M:M
Entity_Connection_One_Direction[ ] Parent / Child

Manditory[ ] or
Optional[ ]

Academic Image Cooperative
Data Model Entity Definitions

SortOrder[3.4]

DIAGRAM_NAME[ Physical Properties]
Entity_Name[ Technique ]
Entity Type
Independent_Entity[ ] or
Dependent_Entity[ ] or
Associative_Entity[ x ] or
Subset_Entity[ ]
Entity_Description[ The Technique entity is a link (associative) file used to connect values in the TechniqueAuthority entity to the WorkItem entity. There is a one-to-many relation between WorkItem and Technique: One record in WorkItem may have zero, one or many records in Technique. It is not mandatory to have Technique cataloged in the Technique entity since there is a TechniqueDisplay field available in the WorkItem entity. However it is recommended.

The Technique entity has a one-to-many relationship to the TechniqueAuthority entity. One record in TechniqueAuthority may be linked to zero, one or many records in the entity Technique.

One record in the Technique entity connects one TechniqueTerm in the TechniqueAuthority to one item in the WorkItem entity.

RULES:

Care must be taken that duplicate connections between a WorkItem and a TechniqueTerm do not exist. Such duplicate links should be prohibited.

If there is an attempt to edit or delete a linked term in the TechniqueAuthority entity, the user/editor should be made aware of the link and be warned before deleting or editing it.

Technique entity records that are not linked to both a TechniqueAuthority record and a WorkItem record should not be allowed to exist. It might be possible to require that both The TechniqueAuthority record and the WorkItem record that form the ends of the link precede in existence the record in the Technique entity. But the Technique entity record should be allowed to exist in transient memory during the process of link creation, but should be saveable only when the links are fashioned.

For example, a procedure: A WorkItem record has been created and is current. The editor attempts to establish a link to a specific technique, say the technique is Sketch which does not exist in the TechniqueAuthority entity. From the Technique entity the user should be able to query the TechniqueAuthority entity.

The term "sketch" is not present. When not present the user should be given an opportunity 1) to consult the AAT or other on-line resource and 2)to add the term into the TechniqueAuthority.

The TechniqueAuthority provides for non-preferred terms and uses a recursive relationship to get to a preferred term from a non-preferred one.

There are a number of similar procedures and links to be established in the database, and this formula or an adaptation of it should be used uniformly for this linking procedure.

The builder of recursive relationships should be prevented from creating circular structures in which parent records are made children of their own children or descendants.

FIELDS:

TechniqueID
TechniqueID is the Key field for the Technique entity. Each value is unique, it is numeric and is assigned sequentially.

WorkItemID
WorkItemID is the foreign key for the relation to the WorkItem entity.

TechForDisplay
This field is a boolean field that indicates that the term selected is important enough to be used in a display of techniques for the linked object. "Y" indicates that it can be used, "N" indicates that it cannot be used.

TechniqueAuthorityID
This is the Foreign Key field that links the Material Entity to the Material Authority.

PROVISIONAL FIELD:

TechniqueNote
This would be a note field in which to record comments on the nature of the link between object and the TechniqueAuthority file. For instance this field may be used to explain where or how the technique is used and, perhaps, its relation to other works of this kind or in the maker's oeuvre. To employ this field it would mean that once a Technique record is linked to a record in the TechniqueAuthority entity it could not be reassigned to a different technique.

]
Entity_Connection_One-Name[ ]
Entity_Connection_One_Cardinality[ ] 1)1:1, 2)1:M, 3)M:M
Entity_Connection_One_Direction[ ] Parent / Child

Manditory[ ] or
Optional[ ]

Academic Image Cooperative
Data Model Entity Definitions

SortOrder[3.5]

DIAGRAM_NAME[ Physical Properties ]
Entity_Name[ TechniqueAuthority ]
Entity Type
Independent_Entity[ x ] or
Dependent_Entity[ ] or
Associative_Entity[ ] or
Subset_Entity[ ]
Entity_Description[ The TechniqueAuthority entity is an authority file composed of terms taken from the Art and Architecture Thesaurus and from other sources that are to be used to indicate which materials are used in a particular work of art. (See VRA Core V.2.0, W5.)

It is linked to the associative entity Technique in a one-to-many relation. One record in the TechniqueAuthority entity may link to zero, one or many records in the Technique entity.

See discussion in the Technique entity description for the rules that govern the making and unmaking of relations between TechniqueAuthority and WorkItem.

The TechniqueAuthority entity contains a recursive structure that permits finding a "preferred term" associated with a "non-preferred term"

Data for the TechniqueAuthority may be derived (preferably)from established authority sources such as the techniques hierarchy in the Art and Architecture Thesaurus or from Revised Nomenclature. But it can also support local terms or terms preferred by the AIC editors.

Query procedure. See also note below under the field: TechniqueAuthorityID/1. When a user queries the TechniqueTerm in the TechniqueAuthority entity he should be aided by several tools: 1) if a search by string is initiated the results should show a list of TechniqueTerm values that correspond to the searched string. In such a case the user should be allowed to choose from among (one or more) values to use to continue the query. or 2) if a user begins to type in a value for a Technique Term, a query list of potential hits should be displayed. The list gets shorter in conjunction with the number of characters entered. 3) The reader should have available a history list of terms used in the current session. This procedure should be available for most situations where queries are allowed.

Rules:
The builder of recursive relationships should be prevented from creating circular structures in which parent records are made children of their own children or descendants.

FIELDS:

TechniqueAuthorityID
This is the key field for the TechniqueAuthority entity. It is unique and is added to sequentially. Deleted records cancel the value in the key field.

TechniqueClassification
This is a one-level classification scheme that may be used to arrange the terms being collected. The classification is to be developed by the AIC cataloger.

TechniqueTerm
This field contains the term that identifies (one of) the processes or techniques used to create the object in WorkItem. It should be taken from an authorized list such as the AAT whenever possible.

Values in this field are required and are indexed for uniqueness.

TechniqueSource
This field identifies the name of the terminology source from which the term in TechniqueTerm has been taken. There should be an authority list for these sources. In addition, these sources should be identified in the bibliography file. [Not implemented in this scheme is a link from the TechniqueAuthority entity to the bibliography file.]

TechniqueSourceCode
Some terminology sources identify their thesaurus entries by code, often numeric. This field provides the editor opportunity to record the appropriate code for the term in TechniqueTerm.

TechniqueTermPreferred
This Boolean field indicates whether the term that appears in TechniqueTerm is a preferred term or a non-preferred term. If the field is "Y" or "True" then it is a preferred term and can be used. If it is not preferred (i.e. the field is "N" or "False") then the term is not legitimate for this database (but should be available for queries). In that case the field entitled MaterialPreferredTerm contain the MaterialAuthorityID of the record that is preferred. See below.

TechniquePreferredTermID
See above. If TechniqueTermPreferred is "False" or "N" then this field contains the record number (TechniqueAuthorityID) of the record that contains the preferred term. The editor is given the opportunity to query this record number and attach the Technique entity record to the TechniqueAuthority record corresponding to the preferred term. But see below.

I expect that this field serves the purpose I had in mind by defining TechniquePreferredTerm (above). In such case TechniquePreferredTerm should be deleted.

This contains the value of the primary key field of the preferred term when the TechniqueTerm field is marked as "non-preferred." Having non-preferred terms in the database increases the likelihood that user queries will be successful.

Queries: When a user queries for a non-preferred term, the search procedure should follow the link in TechniqueuthorityID/1 and present the preferred term to use. The user should be informed that he has hit a non-preferred term.

]
Entity_Connection_One-Name[ ]
Entity_Connection_One_Cardinality[ ] 1)1:1, 2)1:M, 3)M:M
Entity_Connection_One_Direction[ ] Parent / Child

Manditory[ ] or
Optional[ ]

Academic Image Cooperative
Data Model Entity Definitions

SortOrder[3.6]

DIAGRAM_NAME[ Physical Properties ]
Entity_Name[ Measurements ]
Entity Type
Independent_Entity[ ] or
Dependent_Entity[ ] or
Associative_Entity[ x ] or
Subset_Entity[ ]
Entity_Description[ The Measurements entity corresponds to the VRA Core (Ver 2.0) category W.3. Measurements. The values in this entity answer the question: "What are the proportions or size of the work?"

In the WorkItem entity the field (attribute) MeasurementsDisplay offers the editor an opportunity to represent fundamental measurements in a narrative formatted manner, suitable for presentation. MeasurementsDisplay is not a repeatable (multi-valued) field.

The Measurements entity provides the multi-valued attributes needed to record correctly the physical properties of dimension, weight, size, shape and scale: its extent.

Each record in the Measurements entity unites three elements that, together, provide sufficient data to record a single measurement or size. 1) What is the measurement of: height, width, depth, weight, diameter of base, shoe size, wire gauge, etc. 2) How many units of measurements make up the extent of the measurement. This is typically a number but it may be "small" or a unit of duration. 3) What are the units of measure being recorded? Here inches, mm, miles, seconds, or the name of whatever standard is being used (AWG wire gauge, for instance). [See http://w3.uwyo.edu/~metal/gage.html on gauge/gage.]

Measurements is related to WorkItem in a one-to-many structure. One record in WorkItem may relate to zero, one or many records in Measurements.

Measurements is related to two authority files, one for what kind of element is measured (WhatIsMeasuredAuthority) and one in which to register the unit or authority of the measurement extent (UnitOfMeasureAuthority). There is a one-to-many relationship between Measurements and WhatIsMeasuredAuthority and a one-to-many relationship between Measurements and UnitOfMeasureAuthority.

The WhatIsMeasuredAuthority entity has a one-to-many relationship to the entity Measurement. One record in the WhatIsMeasuredAuthority may link to zero, one or many records in Measurements. If a record for Measurements exists then it is manditory that a link be forged to a record in the WhatIsMeasuredAuthority entity and it is manditory that a link be forged to a record in the UnitOfMeasureAuthority.

In Measurements I have provided for the name of the element measured to be imported into the Measurement record and for the name of the unit to be imported into the Measurement record while keeping the link to the authority files alive. The purpose is to ease in reporting since the three elements written into the Measurements record are always rendered together. Because in many cases the Unit of measure is understood, it is possible to omit the unit from the field UnitOfMeasure while keeping the link to the term alive.

The Measurements entity in its relationship to the WorkItem entity and to the two authority files (WhatIsMeasuredAuthority and UnitOfMeasureAuthority) must maintain link integrity. If a record in UnitOfMeasureAuthority is linked to Measurements it may not be changed until it is unlinked. Same for WhatIsMeasuredAuthority. See, further, notes on this topic in the description of the Materials and Technique entities.

A Measurement entity record however, cannot be written to disk until it is linked to a WorkItem record, a WhatIsMeasuredAuthority record, and a UnitOfMeasureAuthority record.

For the Prototype:
In all likelihood the Measurement facility will not be used during the first implementation of the AIC(AIC) database, but it is necessary ultimately to record exact measurements when available. Development of these elements may be postponed until post prototype development if time is short.

See also: Discussion on unit conversion in section on the field MeasurementsDisplay.

FIELDS:

MeasurementsID
This field is the primary key field for the Measurements entity. It is assigned sequentially and deletes values when records are removed.

WorkItemID
This is the foreign key for the entity Measurements. It establishes the link to the entity WorkItem.

WhatIsMeasured
WhatIsMeasured is the name of the element of the work being measured. Width, height, depth, length, etc. This value should be entered automatically by reference to the WhatIsMeasuredAuthoirity entity.

During editing this field should be used as a lookup into the WhatIsMeasuredAuthority entity. As the editor begins to enter a value the WhatIsMeasuredAuthority entity should report back matching values from the WhatIsMeasuredAuthorityTerm field. Or if a string search is entered the entire set of values in the WhatIsMeasuredAuthorityTerm field should be searched. For example if the editor is entering a value for "narrowest diameter of a vessel's neck" and enters "diameter" all the values containing that string should appear, allowing the editor to choose one. If no value appears the editor should be given the opportunity to enter a new value in the WhatIsMeasuredAuthorityTerm field of the WhatIsMeasuredAuthority entity.

Extent
This field typically is filled with a number such as the number of inches or the number designating a size. Catalogers should determine syntax rules for the representation of fractions and other non-integer references. Extent can also be a narrative term like "small," "medium," or "large."

UnitOfMeasure
UnitOfMeasure is the name of the scale used to take the measurement. Inches, miles, AWG wire gauge. These values should be taken from the UnitOfMeasureAuthority file, and inserted into this field directly from it. But, at times, it may be preferable to omit the name of the unit from this field while keeping the link to the UnitOfMeasureAuthority file.

MeasurementNote
Because it is unlikely that measurements entered into records in the Measurements entity have been taken directly from the work, there may be occasion to describe the source of the measurement or any particular information about the measurement, including references to its approximation or accuracy or the measurement or its source.

WhatIsMeasuredAuthorityID
This is the foreign key linking the Measurements entity to the WhatIsMeasuredAuthority entity.

UnitOfMeasureAuthorityID
This is the foreign key linking the Measurements entity to the UnitOfMeasureAuthority.

]
Entity_Connection_One-Name[ ]
Entity_Connection_One_Cardinality[ ] 1)1:1, 2)1:M, 3)M:M
Entity_Connection_One_Direction[ ] Parent / Child

Manditory[ ] or
Optional[ ]

Academic Image Cooperative
Data Model Entity Definitions

SortOrder[3.7]

DIAGRAM_NAME[ Physical Properties ]
Entity_Name[ WhatIsMeasuredAuthority ]
Entity Type
Independent_Entity[ x] or
Dependent_Entity[ ] or
Associative_Entity[ ] or
Subset_Entity[ ]
Entity_Description[ The WhatIsMeasuredAuthority entity is a list of the items measurements are taken of. The terms should be defined exactly to describe the nature of the measurement. For a round table, for instance, one might use "diameter" when diameter can only refer to the top of the table, but one must say "narrowest diameter of the neck" if a vessel is being measured with a variety of diameter measurements possible.

The purpose of this list is to help insure that consistency is being used when naming items measured. Use of this entity for editing should work in conjunction with editing the contents of the WhatIsMeasured attribute (field) in the Measurements entity.

Predominant values in this entity will be simple and straightforward -- height, width, depth, etc.

FIELDS:

WhatIsMeasuredAuthorityID
This is the primary key for the WhatIsMeasuredAuthority entity. Numbers are assigned serially. When a record is deleted the value of the WhatIsMeasuredAuthorityID is retired.

WhatIsMeasuredAuthorityTerm
This is the word or phrase that describes what is being measured. Each value in this field must be unique, indexed and required.

Entry and editing tools should follow the standards discussed elsewhere for similar authority fields.

WMATNote
This is a notefield in which to explain the meaning of the term and to offer scope notes or history notes. For example, if the authority term is "width" the note may explain that for a painting "width" means without the frame. Or the editor may wish to establish "width without frame" as one value and "width with frame" as another and leave "width" when used for two-dimensional art for instances in which it is not known whether frames and/or borders have been included or not.

]
Entity_Connection_One-Name[ ]
Entity_Connection_One_Cardinality[ ] 1)1:1, 2)1:M, 3)M:M
Entity_Connection_One_Direction[ ] Parent / Child

Manditory[ ] or
Optional[ ]

Academic Image Cooperative
Data Model Entity Definitions

SortOrder[3.8]

DIAGRAM_NAME[ Physical Properties ]
Entity_Name[ UnitOfMeasureAuthority ]
Entity Type
Independent_Entity[ x] or
Dependent_Entity[ ] or
Associative_Entity[ ] or
Subset_Entity[ ]
Entity_Description[ The UnitOfMeasureAuthority typically explains the meaning of the value placed in the Extent field of the Measurements entity. It may be "inches" or "feet" or "meter" but it may also be "pounds" or "kilograms." On some occasions the WhatIsMeasuredTerm entered into the WhatIsMeasured field in the Measurements entity defines both what is measured and the scale used to register the measurement. For example, shirt size or wire gauge or octavo implies units of measurement. In such cases the UnitOfMeasureAuthority can be used to document the agencies and/or traditions that produced the scale. Because in some cases the Units are understood, it may not be necessary to enter a value from this authority list into the UnitOfMeasure field in the Measurements entity.

The UnitOfMeasureAuthority entity is related in a one-to-many relationship with the Measurements entity. One record in the UnitOfMeasureAuthority can be linked to multiple records in the Measurement entity. Each record in Measurements must be linked to a record in the UnitOfMeasureAuthority. Rules should make it impossible to delete a record in the UnitofMeasureAuthority until it is no longer linked to any Measurement Record. A Measurement entity record however, cannot be written to disk until it is linked to a WorkItem record, a WhatIsMeasuredAuthority record, and a UnitOfMeasureAuthority record.

FIELDS:

UnitOfMeasureAuthorityID
This is the primary key for the UnitOfMeasureAuthority entity. Numbers are assigned serially. When a record is deleted the value of the UnitOfMeasureAuthorityID is retired.

UnitOfMeasureAuthorityTerm
This is the word or phrase that describes what convention is being used to measure the object. Answerable in "inches," "meters," "pouce," "AWG wire gauge," etc. Values in this field are required. Each value in this field must be indexed for uniqueness.

Entry and editing tools should follow the standards discussed elsewhere for similar authority fields.

UOATNote
This is a notefield in which to explain the meaning of the term and to offer scope notes or history notes. For example, if the authority term is "pouce" the note may explain that this unit of measurement was used in pre-revolutionary France and (meaning Thumb) is approximately one inch long.

General note:
Catalogers may wish to decide upon the conventions of citing units. Will units be cited in singular or plural? Are abbreviations appropriate. Perhaps the note field should indicate common abbreviations for the designated unit.

]
Entity_Connection_One-Name[ ]
Entity_Connection_One_Cardinality[ ] 1)1:1, 2)1:M, 3)M:M
Entity_Connection_One_Direction[ ] Parent / Child

Manditory[ ] or
Optional[ ]