5.1 File Header Logical Record (FHLR)
Each Logical
File begins with a File Header Logical Record that serves as an
identifying label for the Logical File. A File Header Logical Record
is an Explicitly Formatted Logical Record (EFLR) with Type FHLR.
A File Header Logical Record contains a single FILE-HEADER
Set. A FILE-HEADER Set is unnamed and contains exactly one Object
with two Attributes as defined in Figure 5-1.
The Origin Subfield of the Name of the File-Header
Object must reference the Defining Origin (see §5.2.1).
The Identifier
Subfield is a single arbitrary character.
The Template Attributes for this Set must contain
explicitly the Label and Representation Code Characteristics and
only the Label and Representation Code Characteristics. The Count,
Units, and Value Characteristics take the global defaults. The
Value Characteristics are later defined in the Object's Attributes.
| Label
| Restrictions
| Comments
| SEQUENCE-NUMBER
| C=1, R=ASCII, U=absent
| 1
|
| ID
| C=1, R=ASCII, U=absent
| 2
Figure 5-1. Attributes of File-Header Object
| |
Comments:
- 1.The Sequence-Number Attribute is
the ASCII representation of a positive integer that indicates the
sequential position of the Logical File in a Storage Set. The Value
of the Sequence-Number Attribute must meet the following requirements:
- The number of ASCII characters is fixed at 10 characters,
right justified and padded to the left with blank
characters (ASCII code 3210).
That is, the character representing the
least significant digit of the Sequence-Number is in byte 10.
- The Sequence-Number of any Logical File,
expressed as an integer, must be greater than the
Sequence-Number of the Logical File that immediately precedes
it in the Storage Set. The Sequence-Number of the first
Logical File in a Storage Set may be any positive integer.
- 2.The ID
Attribute is a descriptive
identification of the Logical File. The Value of the ID Attribute
must meet the following requirement:
- The number of ASCII characters is fixed
at 65 characters (width of a standard printed page).
Since the File Header Logical Record is required
to be written as a single Logical Record Segment (see §2.2.3.1),
a general file management utility can identify File Header Logical
Records, modify the Value of the Sequence-Number Attribute, and
retrieve the Values of both the Sequence-Number and ID Attributes
knowing only the following about DLIS Logical Records (see Figure
5-2):
- Bit 1 in byte 3 of a File Header Logical
Record Segment is set and byte 4 contains the numeric code FHLR
(see Appendix A).
- The Value (excluding the length byte) of
the Sequence-Number Attribute is in
bytes 48 through 57 inclusive.
- The Value (excluding the length byte) of
the ID Attribute is in bytes 60 through 124 inclusive.
- When searching for a File Header Logical
Record on Record Storage Units, only the first
Logical Record Segment
in each Visible Record needs to be read.
It begins following the
two-byte Format Version, which follows
the two-byte Visible Record Length.
The first byte of the first Logical Record Segment is byte
5 of the Visible Record in a Record Storage Unit.
Figure 5-2. Byte Structure of File Header Logical Record
5.2 Origin Logical Record (OLR)
Origin Logical
Records are Explicitly Formatted Logical Records of Type OLR that
contain Objects that provide information about the original conditions
under which the information in the Logical File was acquired or
created. Origin Logical Records may contain Set Types ORIGIN
and WELL-REFERENCE-POINT.
5.2.1 Origin Objects
ORIGIN Objects uniquely identify Logical Files and
describe the basic circumstances
under which Logical Files are created.
ORIGIN Objects also provide
a means for distinguishing different instances of a given entity.
Each Logical File must contain at least one ORIGIN
Set, which may contain one or more ORIGIN Objects. The first Object
in the first ORIGIN Set is the Defining Origin for the Logical
File in which it is contained, and the corresponding Logical File
is called the Origin'’s Parent File. It is intended that
no two Logical Files will ever have Defining Origins with all Attribute
Values identical.
Figure 5-3 defines the Attributes of an ORIGIN Object.
Label
Restrictions
Comments
| FILE-ID
| C=1, R=ASCII
| 1
| FILE-SET-NAME
| C=1, R=IDENT
| 2
| FILE-SET-NUMBER
| C=1, R=UVARI
| 3
| FILE-NUMBER
| C=1, R=UVARI
| 4
| FILE-TYPE
| C=1, R=IDENT
| 5
| PRODUCT
| C=1, R=ASCII
| 6
| VERSION
| C=1, R=ASCII
| 7
| PROGRAMS
| R=ASCII
| 8
| CREATION-TIME
| C=1, R=DTIME
| 9
| ORDER-NUMBER
| C=1, R=ASCII
| 10
| DESCENT-NUMBER
|
| 11
| RUN-NUMBER
|
| 12
| WELL-ID
| C=1
| 13
| WELL-NAME
| C=1, R=ASCII
| 14
| FIELD-NAME
| C=1, R=ASCII
| 15
| PRODUCER-CODE
| C=1, R=UNORM
| 16
| PRODUCER-NAME
| C=1, R=ASCII
| 17
| COMPANY
| C=1, R=ASCII
| 18
| NAME-SPACE-NAME
| C=1, R=IDENT
| 19
| NAME-SPACE-VERSION
| C=1, R=UVARI
| 20
Figure 5-3. Attributes of Origin Object
| | | | | | | | | | | | | | | | | | | | | | |
Comments:
- 1.
The File-ID Attribute is an exact
copy of the ID Attribute of the File-Header Object of the Parent
File, i.e., the Logical File for which this Origin Object is the
Defining Origin.
- 2.
The File-Set-Name Attribute is the
name of a File Set, a group of Logical Files related
according to Producer-defined criteria to which the Parent File
belongs. The File Set is an arbitrary grouping of a set of Logical
Files and has no DLIS semantic meaning. The File-Set-Name Attribute
is not expected to be unique for all File Sets.
- 3.
The File-Set-Number Attribute is
a random number, called the File Set Number, that
is used to distinguish the Logical Files of one File Set from the
Logical Files of another File Set. This number should be such that
there is a high probability that it uniquely identifies the File
Set. This number should be the same for all Logical Files of a
given File Set. This Attribute must be present, even when the
File-Set-Name
Attribute is absent. In that case, it is considered to apply to
the File Set consisting of the single current Logical File.
- 4.
The File-Number Attribute is the
File Number of the Parent File relative to the File
Set specified by the File-Set-Name Attribute. File Numbers for
a File Set are positive and increase in the order in which the Logical
Files of the File Set are created. File Numbers for a File Set
need not increase sequentially.
It should be true, with a high probability,
that no two Logical Files will ever have the same File Set Number
and File Number combination.
Notice that there is no specific relationship
defined for File Numbers of Logical Files in the same Storage Set.
In particular, a File Set may or may not coincide with the Logical
Files of a Storage Set.
- 5.
The File-Type Attribute is a Producer-specified
File Type and signifies the general contents of the
Parent File or the circumstances under which the Parent File was
created.
- 6.
The Product Attribute is the name
of the software product (e.g., the wellsite "operating"
system) that produced the Parent File.
- 7.
The Version Attribute is the version
of the product specified by the Product Attribute.
- 8.
The Programs Attribute is a List
of the names of a specific programs or services, operating as part
of the software specified by the Product Attribute, that were used
to generate the data contained in the Parent File.
- 9.
The Creation-Time Attribute is the
date and time at which the Parent File was created.
- 10.
The Order-Number Attribute is a
unique accounting number associated with the acquisition or creation
of the data in the Parent File. It is typically known as the
Service Order Number.
- 11.
The Descent-Number Attribute is
meaningful to the Producer. The meaning of this number is specified
by the Producer to the Consumer by means external to the DLIS.
- 12.
The Run-Number Attribute is meaningful
to the company specified in the Company Attribute. Its use is
specified
to the Producer by this company by means external to the DLIS.
- 13.
The Well-ID Attribute is a codified
identifier of the well in or about which measurements were taken.
Whenever applicable, the API Well Number should be used. This
is a unique, permanent, numeric identifier assigned to a well in
accordance with the American Petroleum Institute Bulletin D12A,
January, 1979.
- 14.
The Well-Name Attribute is the name of the well.
- 15.
The Field-Name Attribute is the
name of the Field to which the well belongs. If there is no Field,
then the value of this Attribute should be WILDCAT.
- 16.
The Producer-Code Attribute is
the Producer’s identifying code. The Producer is the company whose
authorized agent generated the Logical File using software programs
developed under the sponsorship of the company. This code is assigned
on request by POSC.
A list of current Company Codes for Producers may be obtained from
the same source.
- 17.
The Producer-Name Attribute is
the Producer’s business or organization name
- 18.
The Company Attribute is the name
of the client company for which the data was acquired or computed,
typically the operator of the well.
- 19.
The Name-Space-Name Attribute specifies
the name of the dictionary in which dictionary-controlled Object
Names are administered for this Origin. Each Producer is expected
to administer or subscribe to a dictionary of Object Names from
which meaningful definitions can be derived.
- 20.
The Name-Space-Version Attribute
specifies the version of the dictionary in which dictionary-controlled
Object Names are administered for this Origin. Dictionary version
N is a superset of dictionary version M whenever N > M.
Well-Reference-Point
Objects specify the Well Reference Point of a well (see §4.1.8).
Figure 5-4 defines the Attributes of a Well-Reference-Point
Object.
| Label
| Restrictions
| Comments
| PERMANENT-DATUM
| C=1, R=ASCII
| 1
|
| VERTICAL-ZERO
| C=1, R=ASCII
| 2
|
| PERMANENT-DATUM-ELEVATION
| C=1
| 3
|
| ABOVE-PERMANENT-DATUM
| C=1
| 4
|
| MAGNETIC-DECLINATION
| C=1
| 5
|
| COORDINATE-1-NAME
| C=1, R=ASCII
| 6
|
| COORDINATE-1-VALUE
| C=1
| 7
|
| COORDINATE-2-NAME
| C=1, R=ASCII
| 8
|
| COORDINATE-2-VALUE
| C=1
| 9
|
| COORDINATE-3-NAME
| C=1, R=ASCII
| 10
|
| COORDINATE-3-VALUE
| C=1
| 11
Figure 5-4. Attributes of Well-Reference-Point Object
| |
Comments:
- 1.The Permanent-Datum Attribute specifies
a Permanent Datum, an entity or structure (e.g., Ground Level)
from which vertical distance can be measured.
- 2.The Vertical-Zero Attribute specifies
Vertical Zero, a particular entity (e.g., Kelly Bushing)
that corresponds to zero depth.
- 3.The Permanent-Datum-Elevation Attribute
specifies the distance of the Permanent Datum above mean sea level.
A negative value indicates that the Permanent Datum is below mean
sea level.
- 4.The Above-Permanent-Datum Attribute
specifies the distance of Vertical Zero above the Permanent Datum.
The distance can be negative, which indicates that Vertical Zero
is below the Permanent Datum.
- 5.The Magnetic-Declination Attribute
specifies the angle with vertex at the Well Reference Point determined
by the line of direction to geographic north and the line of direction
to magnetic north. A positive value indicates that magnetic north
is east of geographic north. A negative value indicates that magnetic
north is west of geographic north.
- 6.The Coordinate-1-Name Attribute
specifies the name of the first of three independent spatial coordinates,
such as longitude or latitude or elevation, that can be used to
locate the Well Reference Point.
- 7.The Coordinate-1-Value Attribute
specifies the numerical value of the coordinate named by the Coordinate–1-Name
Attribute.
- 8.The Coordinate-2-Name Attribute
specifies the name of the second of three independent spatial coordinates
that can be used to locate the Well Reference Point.
- 9.The Coordinate-2-Value Attribute
specifies the numerical value of the coordinate named by the Coordinate–2-Name
Attribute.
- 10.The Coordinate-3-Name Attribute
specifies the name of a third independent spatial coordinate that
can be used to locate the Well Reference Point.
NOTE: Traditionally the coordinates
of a well are described by latitude, longitude, and elevation.
This information can be represented in the Well-Reference-Point
Object without using Coordinate-3-Name and Coordinate-3-Value.
There are other coordinate systems in use, however, that do not
use elevation and for which the third general coordinate is needed.
- 11.The Coordinate-3-Value Attribute
specifies the numerical value of the coordinate named by the Coordinate–3-Name
Attribute.
5.3 Axis Logical Record (AXIS)
An Axis
Logical Record is an Explicitly Formatted Logical Record that contains
information describing the coordinate axes of arrays.
Axis Logical Records contain the single Set Type
AXIS.
5.3.1 Axis Objects
Axis Objects
describe the coordinate axes of an array (see §4.4.4). Each Axis
Object describes one coordinate axis.
Figure 5-5 defines the Attributes of an Axis
Object.
Comments:
- 1.The Axis-ID Attribute is a dictionary-controlled
identifier for the coordinate axis described by this Object.
- 2.The Coordinates Attribute specifies
explicit coordinate values along a coordinate axis. These values
may be numeric (i.e., for non-uniform coordinate spacing), or they
may be textual identifiers, for example "Near" and "Far".
If the Coordinates Value has numeric Elements, then they must occur
in order of increasing or decreasing value. The Count of the Coordinates
Attribute need not agree with the number of array elements along
this axis specified by a related Dimension Attribute.
- 3.The Spacing Attribute specifies
a constant, signed spacing along the axis between successive coordinates,
beginning at the last coordinate value specified by the Coordinates
Attribute. If the Coordinates Attribute is non-numeric or absent,
then the specified spacing is assumed to exist between every pair
of successive coordinate values along the axis, and the first coordinate
value is assumed to be zero (0).
5.4" Long Name Logical Record (LNAME)
A Long Name
Logical Record is an Explicitly Formatted Logical Record that contains
structured Long Names of Objects.
Long Name Logical Records contain the single
Set Type Long-Name.
5.4.1 Long-Name Objects
Long-Name
Objects represent structured names of other Objects. A Long–Name
Object is referenced by (an Attribute of) the Object of which it
is the structured name.
There are standardized Name Part Types corresponding
to the Labels of the Attributes of the Long-Name Object. For each
Name Part Type there is a dictionary-controlled Lexicon of Name
Part Values. A Name Part Value is a word or phrase. The Long Name
is built by selecting those Name Part Types that are applicable
to an Object and then selecting for each Name Part Type one or more
Name Part Values from the corresponding Lexicons.
A reference to a Long-Name Object establishes
a binding between the Long Name and the Identifier of the Object
making the reference. Over a period of time the Long Name that
is associated with a particular Identifier (for a given Object Type)
may evolve, but only to clarify its meaning or to exchange a Name
Part Value with an industry-preferred synonym. The Identifier of
the referencing Object retains its original usage forever.
Figure 5-6 defines the Attributes of a Long-Name
Object.
| Label
| Restrictions
| Comments
| GENERAL-MODIFIER
| R=ASCII
| 1
|
| QUANTITY
| C=1, R=ASCII
| 2
|
| QUANTITY-MODIFIER
| R=ASCII
| 3
|
| ALTERED-FORM
| C=1, R=ASCII
| 4
|
| ENTITY
| C=1, R=ASCII
| 5
|
| ENTITY-MODIFIER
| R=ASCII
| 6
|
| ENTITY-NUMBER
| C=1, R=ASCII
| 7
|
| ENTITY-PART
| C=1, R=ASCII
| 8
|
| ENTITY-PART-NUMBER
| C=1, R=ASCII
| 9
|
| GENERIC-SOURCE
| C=1, R=ASCII
| 10
|
| SOURCE-PART
| R=ASCII
| 11
|
| SOURCE-PART-NUMBER
| R=ASCII
| 12
|
| CONDITIONS
| R=ASCII
| 13
|
| STANDARD-SYMBOL
| C=1, R=ASCII
| 14
|
| PRIVATE-SYMBOL
| C=1, R=ASCII
| 15
Figure 5-6. Attributes of Long-Name Object
| |
Comments:
- 1.The GENERAL-MODIFIER Attribute qualifies
the Long Name otherwise specified by all the remaining Attributes
of the Long-Name Object.
- 2.The QUANTITYAttribute specifies
something that is measurable, for example physical dimensionality,
or some classifiable feature of an entity, for example a name or
color or shape.
- 3.The QUANTITY-MODIFIER Attribute
identifies a specialization of a quantity; that is, it acts as an
adjective applied to the Quantity Attribute Value.
- 4.The ALTERED-FORMAttribute specifies
a relationship to the Quantity Attribute Value. For example, "Standard
Deviation" is an altered form of the quantity "Pressure".
- 5.The ENTITYAttribute specifies that
thing of which the quantity is measured. For example, "Diameter"
is a quantity of the entity "Borehole".
- 6.The ENTITY-MODIFIERAttribute identifies
a specialization of an entity; that is, it acts as an adjective
applied to the Entity Attribute Value.
- 7.The ENTITY-NUMBERAttribute distinguishes
multiple instances of the same entity.
- 8.The ENTITY-PARTAttribute identifies
a specific part of an entity.
- 9.The ENTITY-PART-NUMBERAttribute
distinguishes multiple instances of the same entity part, for example,
"Button 1", "Arm 2".
- 10.The GENERIC-SOURCEAttribute specifies
briefly and generally the source of the information. The generic
source of a borehole diameter measurement might be either "2-Arm
Caliper" or "4–Arm Caliper".
- 11.The SOURCE-PARTAttribute identifies
a specific part of the source of the information specified by the
Generic-Source Attribute, for example, "Receiver" or "Transmitter".
- 12.The SOURCE-PART-NUMBERAttribute
distinguishes multiple instances of the same source part.
- 13.The CONDITIONSAttribute specifies
conditions applicable at the time the information was acquired or
generated. A condition of resistivity, for example, is "At
Standard Temperature."
- 14.The STANDARD-SYMBOL Attribute is
an industry-standardized symbolic name by which the information
is known. The possible values of this Attribute are specified by
POSC. Consequently, this Attribute is optional and is used only
when an applicable standardized name exists.
- 15.The PRIVATE-SYMBOL Attribute provides
an association between the recorded information and corresponding
records or objects of the Producer’s internal or corporate database.
The value used in this Attribute and the way in which the value
is assigned are completely at the discretion of the Producer that
is identified in the Origin Object associated with the Long Name
Object.
5.5 Channel Logical Record (CHANNL)
A Channel
Logical Record is an Explicitly Formatted Logical Record that contains
information defining and characterizing Channels (see §4.1.4).
Channel Logical Records contain the single Set
Type Channel.
5.5.1 Channel Objects
Channel
Objects are dictionary-controlled Objects that identify Channels
and specify their properties and their representation in Frames.
The actual Channel sample values are recorded in Indirectly Formatted
Logical Records, when present.
Figure 5-7 defines the Attributes of a Channel Object.
| CHANNEL Object Names are dictionary-controlled.
|
| Label
| Restrictions
| Comments
| LONG-NAME
| C=1, R=(OBNAME< ASCII)
| -
|
| PROPERTIES
| R=IDENT
| 1
|
| REPRESENTATION-CODE
| C=1, R=USHORT
| 2
|
| UNITS
| C=1, R=UNITS
| 3
|
| DIMENSION
| R=UVARI
| 4
|
| AXIS
| R=OBNAME
| -
|
| ELEMENT-LIMIT
| R=UVARI
| 5
|
| SOURCE
| C=1, R=OBJREF
| 6
Figure 5-7. Attributes of Channel Object
| |
Comments:
- 1.The PROPERTIES Attribute is a List
of Property Indicators (see Appendix C). The Property Indicators
summarize the characteristics of the Channel and the processing
that has occurred to produce it.
- 2.The REPRESENTATION-CODE Attribute
specifies the Representation Code of each element of a sample value.
- 3.The UNITS Attribute specifies the
physical units of each element of a sample value.
- 4.The DIMENSION Attribute specifies
the array structure of a sample value for the Channel (see §4.4.3).
- 5.The ELEMENT-LIMIT Attribute specifies
limits on the dimensionality and size of a Channel sample. The
Count of this Attribute specifies the maximum allowable number of
dimensions, and each Element of this Attribute specifies the maximum
allowable size of the corresponding dimension in array elements.
For example, if Element-Limit = {5 10 50},
then a Channel sample may have 0, 1, 2, or 3 dimensions. The first
dimension size may be no larger than 5 elements, the second no larger
than 10 elements, and the last no larger than 50 elements. Within
these limits, the Channel sample may be of arbitrary size as specified
by the Dimension Attribute (which is updatable).
- 6.The SOURCE Attribute is a reference
to another Object that describes the immediate source of the Channel,
for example, a TOOL, PROCESS, SPLICE, or CALIBRATION Object.
5.6 Frame Data Logical Records (FDATA)
Frame Data
Logical Records are Indirectly Formatted Logical Records that record
Channel data packaged in Frames (see §4.1.5).
A Frame
constitutes the Indirectly Formatted Data of a Type FDATA Indirectly
Formatted Logical Record (IFLR). The Data Descriptor Reference
of the FDATA Logical Record refers to a Frame Object, defined
in Figure 5–8, and defines the Frame Type of the Frame.
Frames of a given Frame Type occur in sequences
within a single Logical File. A Frame is segmented into a Frame
Number, followed by a fixed number of Slots that contain
Channel samples, one sample per Slot. The Frame Number is an integer
(Representation Code UVARI) specifying the numerical order of the
Frame in the Frame Type, counting sequentially from one. All Frames
of a given Frame Type record the same Channels in the same order.
The IFLRs containing Frames of a given Type need not be contiguous.
A Frame Type may or may not have an Index
Channel. If there is an Index Channel, then it must appear
first in the Frame and it must be scalar. When an Index Channel
is present, then all Channels in the Frame are assumed to be "sampled
at" the Index value. For example, if the Index is depth, then
Channels are sampled at the given depth; if time, then they are
sampled at the given time, etc. Minor variations in this assumption
can be declared explicitly in Path Objects,
which are described later.
The truth of the assumption just stated is relative
to the measuring and recording system used and does not imply absolute
accuracy. For example, depth may be measured by a device that monitors
cable movement at the surface, which may differ from actual tool
movement in the borehole. Corrections that are applied to Channels
to improve the accuracy of measurements or alignments to indices
are left to the higher-level semantics of applications.
When there is no Index Channel, then Frames are
implicitly indexed by Frame Number.
Frame Logical
Records are Explicitly Formatted Logical Records of Type FRAME that
contain Objects that specify the characteristics and form of Frames.
Frame Logical Records can contain Set Types Frame;, and
Path.
Each Frame
Object defines a Frame Type, lists the Channels recorded in the
Frame Type, and characterizes the Index of that Frame Type. The
Frame Type is equal to the Name of the Frame Object. In addition,
each Frame Object specifies whether the contents of the Frames of
that Frame Type are encrypted.
Figure 5-8 defines the Attributes of a Frame
Object.
| Label
| Restrictions
| Comments
| DESCRIPTION
| C=1, R=ASCII
| -
|
| CHANNELS
| R=OBNAME
| 1
|
| INDEX-TYPE
| C=1, R=IDENT
| 2
|
| DIRECTION
| C=1, R=IDENT
| 3
|
| SPACING
| C=1
| 4
|
| ENCRYPTED
| C=1, R=USHORT
| 5
|
| INDEX-MIN
| C=1
| 6
|
| INDEX-MAX
| C=1
| 7
Figure 5-8. Attributes of Frame Object
| |
Comments:
- 1.The Channels Attribute; is a List
of references to Channel Objects; that specify the format of the
Frame Type defined by the current Frame Object. Channel samples
are recorded in the Frame in the order in which the Channel Objects
are listed in this Attribute. The format of a sample is specified
by the Representation-Code, Units, and Dimension Attributes of the
corresponding Channel Object. When a Channel Object is referenced
by a Frame Object, the Representation-Code, Dimension, and
Element-Limit Attributes must be present in the Channel Object.
Within a Logical File, no two Frame Objects
may reference the same Channel Object. Informally, this means that
if the same "Channel" is to be recorded in two distinct
Frame Types in a Logical File, then the Channel must be represented
by two distinct Channel Objects, which may differ by as little as
the Copy Numbers in their Names.
- 2.The Index-Type Attribute; specifies
the type of Index, if present.
| INDEX-TYPE Attribute Options
| Description
| ANGULAR-DRIFT
| Index measures angle about the Vertical Generatrix.
|
| BOREHOLE-DEPTH
| Index measures depth along the borehole.
|
| NON-STANDARD
| Index is not a standard measurement.
|
| RADIAL-DRIFT
| Index measures distance from the Vertical Generatrix.
|
| VERTICAL-DEPTH
| Index measures depth along the Vertical Generatrix.
| |
If Attribute Index-Type is absent, then there
is no Index Channel and Attributes Direction and Spacing are meaningless
and are ignored. When Attribute Index-Type is absent, then Frames
are implicitly indexed by the Frame Number.
When a Frame has an Index, then it must be
the first Channel in the Frame, and it must be scalar.
- 3.The DIRECTION Attribute;
specifies the behavior of the signed value of the Index.
If this Attribute
is absent, then Index direction is unknown or irrelevant.
| DIRECTION Attribute Options
| Description
| DECREASING
| Index decreases monotonically.
|
| INCREASING
| Index increases monotonically.
| |
The sequence
{5.2, 3.01, 2.1, 0.0, -1.8, -7.355, ...}
is an example of a decreasing sequence of
Index values, and
{-3.41, -2.6, -1.005, 0.5, 1.23, 6.0, 8.97, ...}
is an example of an increasing sequence of
Index values.
- 4.The Spacing Attribute; can be used
to indicate a constant spacing of the Index from one Frame to the
next. Its value is the signed difference of the later minus the
earlier Index between any (and every) two successive Frames of a
given Frame Type. Thus, the Spacing Attribute is negative if the
Index is decreasing (e.g., an up log) and is positive if the Index
is increasing (e.g., a down log). Note that when Attribute Spacing
is present, then Attribute Direction is not required.
Presence of this Attribute guarantees to
the Consumer that Index spacing will be constant for the current
Frame Type throughout the Logical File. If the Index spacing is
allowed to change, then this Attribute must be absent.
- 5.The Encrypted Attribute; is used
as a flag. That is, only its presence or absence has semantic meaning.
Its presence indicates that IFLRs containing this Frame Type are
encrypted. Its absence indicates that IFLRs containing this Frame
Type are not encrypted. Encrypted Frames typically contain information
considered proprietary by the Producer.
- 6.The INDEX-MIN Attribute specifies
the minimum value of the Index Channel in all Frames of the Frame
Type. If there is no Index Channel, then this is the minimum Frame
Number, namely 1.
- 7.The INDEX-MAX Attribute specifies
the maximum value of the Index Channel in all Frames of the Frame
Type. If there is no Index Channel, then this is the number of
Frames in the Frame Type.
The fundamental
recorded log data consists of a sequence of values (i.e., a Channel)
traversing a Locus in space and time. A Locus in space and
time is a sequence of distinct points, each of which, in the most
general case, has a three-dimensional Position coordinate,
and a Time coordinate. The sequence
{Valuei, Positioni, Timei}
is called a Data Path, and each member
of the sequence is called a Step on the Data Path.
The sequence
{Positioni, Timei}
is the Locus of the Data Path. Note that it
is possible for two points on a Locus to occupy the same Position
in space so long as they occupy that Position at different Times.
In the extreme case, a Locus can have a fixed Position.
A complete Position coordinate is made up of
three components that correspond to the spatial coordinate system
of a well: depth (Borehole or Vertical), Radial Drift, and Angular
Drift. Occasionally, both Borehole and Vertical depth components
are known and are recorded together.
Data Paths are represented as groups of Channels
in Frames. Some or all of the components of a Data Path may be
recorded; other components may be unknown or irrelevant.
The {Valuei} sequence,
known as the Data Path's Value Channel, is always
recorded. The mechanism for defining Data Paths is the Path
Object. Path Objects are not needed to decode Frames, but they
add informational value to the contents of Frames.
Path Objects
specify which Channels in the Data Frames of a given Frame Type
are combined to define part or all of a Data Path, and what variations
in alignment exist.
The Index of a Frame Type automatically and explicitly
serves as a Locus component of any Data Path represented in the
Frame Type whenever Frame Attribute INDEX-TYPE has one of the values
angular-drift, borehole-depth, radial-drift, time, or vertical-depth.
Figure 5-9 defines the Attributes of a Path Object.
| Label
| Restrictions
| Comments
| FRAME-TYPE
| C=1, R=OBNAME
| 1
|
| WELL-REFERENCE-POINT
| C=1, R=OBNAME
| 2
|
| VALUE
| R=OBNAME
| 3
|
| BOREHOLE-DEPTH
| C=1
| 4
|
| VERTICAL-DEPTH
| C=1
| 5
|
| RADIAL-DRIFT
| C=1
| 6
|
| ANGULAR-DRIFT
| C=1
| 7
|
| TIME
| C=1
| 8
|
| DEPTH-OFFSET
| C=1
| 9
|
| MEASURE-POINT-OFFSET
| C=1
| 10
|
| TOOL-ZERO-OFFSET
| C=1
| 11
Figure 5-9. Attributes of Path Object
| |
Comments:
Static Data
Logical Records are Explicitly Formatted Logical Records of Type
STATIC that contain a broad category of Set Types. Static Logical
Records may contain Set Types Zone, Parameter, Equipment,
Tool, PROCESS, Computation, Calibration,
Calibration-Measurement, Calibration-Coefficient,
Splice, and Group.
Zone Objects
specify single intervals in depth or time. Zone Objects are useful
for associating other Objects or values with specific regions of
a well or with specific time intervals.
Figure 5-11 defines the Attributes of a Zone
Object. Zone Object Names are arbitrary.
| Label
| Restrictions
| Comments
| DESCRIPTION
| C=1, R=ASCII
| -
|
| DOMAIN
| C=1, R=IDENT
| 1
|
| MAXIMUM
| C=1
| 2
|
| MINIMUM
| C=1
| 3
Figure 5-11. Attributes of Zone Object
| |
Comments:
- 1.The Domain Attribute indicates the
type of interval.
| DOMAIN Attribute Options
| Description
| BOREHOLE-DEPTH
| Zone interval is depth along the borehole.
|
| TIME
| Zone interval is elapsed time.
|
| VERTICAL-DEPTH
| Zone interval is depth along the Vertical Generatrix.
| |
- 2.The Maximum Attribute is the depth
of the bottom (deepest part) of the zone or the latest time. This
value is not considered to be part of the zone.
- When this Attribute is absent, the zone is
considered to extend indefinitely in the direction corresponding
to deepest or latest.
- 3.The Minimum Attribute is the depth
of the top (shallowest part) of the zone or the earliest time.
This value is considered to be part of the zone.
When this Attribute is absent, the zone is
considered to extend indefinitely in the direction corresponding
to shallowest or earliest.
Parameter Objects are dictionary-controlled Objects
that specify Parameters
(constant or zoned) used in the acquisition and processing of data.
Parameters may be scalar-valued or array-valued. When they are
array-valued, the semantic meaning of the array dimensions is defined
by the application.
Figure 5-12 defines the Attributes of a Parameter
Object.
| PARAMETER Object Names are dictionary-controlled.
|
| Label
| Restrictions
| Comments
| LONG-NAME
| C=1, R=(OBNAME, ASCII)
| -
|
| DIMENSION
| R=UVARI
| 1
|
| AXIS
| R=OBNAME
| -
|
| ZONES
| R=OBNAME
| 2
|
| VALUES
| -
| 3
Figure 5-12. Attributes of Parameter Object
| |
Comments:
- 1.The DIMENSION Attribute specifies
the array structure of a single value of the current Parameter
(see §4.4.4).
- 2.The ZONES Attribute is a List of
references to Zone Objects that specify mutually disjoint intervals
over which the value of the current Parameter is constant. A Parameter
may have different values in different zones. When this Attribute
is present, the Parameter is said to be Zoned, and it is
considered to be defined only in the zones specified by the Zones
Attribute. It is considered to be undefined elsewhere.
The Zone Objects referenced in this List
must all have the same Domain Attribute Value. That is, a Parameter
Object may only be zoned over a single domain.
The Zones Attribute may be absent, in which
case the Parameter is said to be Unzoned. In this case,
the Parameter is considered to be defined everywhere.
- 3.The VALUES Attribute is a List of
Parameter values corresponding to the zones listed in the Zones
Attribute. When the Parameter is Zoned, the number of Parameter
values is the same as the number of zones referenced, and the
kth Parameter
value applies to the
kth zone. When the Parameter is Unzoned, there
is a single Parameter value in the Values Attribute.
The Count of the Values Attribute is equal
to the number of Parameter values listed (equal to 1 if Unzoned
or determined by the Count of the Zones Attribute if Zoned) multiplied
by the size in elements of each value (determined by the Dimension
Attribute). For example, if there are three zones, and if Dimension
= {3, 4, 128}, then there are three Parameter values listed, each
1,536 elements big, making the Count of the Values Attribute equal
to 3*1,536 = 4,608.
Equipment Objects are dictionary-controlled Objects
that specify the presence
and characteristics of surface and downhole equipment used in the
acquisition of data. The purpose of this Object is to record information
about individual pieces of equipment of any sort that is used during
a job. The Tool Object, described below, provides a way to collect
equipment together in ensembles that are more readily recognizable
to the Consumer.
Figure 5-13 defines the Attributes of an Equipment
Object.
Figure 5-13. Attributes of Equipment Object
Comments:
- 1.The TRADEMARK-NAME Attribute
specifies the name used by the Producer to refer to the Equipment.
- 2.TheSTATUS Attribute
indicates the operational status of the equipment.
- 3.TheTYPEAttribute
specifies the generic type of the equipment.
| TYPE Attribute Options
| Description
| Adapter
| Adapter
|
| Board
| Processor board
|
| Bottom-Nose
| Bottom-Nose
|
| Bridle
| Bridle
|
| Cable
| Cable
|
| Calibrator
| Calibrator
|
| Cartridge
| Cartridge
|
| Centralizer
| Centralizer
|
| Chamber
| Sample chamber
|
| Cushion
| Water cushion
|
| Depth-Device
| Depth measuring device
|
| Display
| Display
|
| Drawer
| Processor drawer
|
| Excentralizer
| Excentralizer
|
| Explosive-Source
| Explosive source
|
| Flask
| Flask
|
| Geophone
| Geophone
|
| Gun
| Gun
|
| Head
| Head
|
| Housing
| Housing
|
| Jig
| Calibration jig
|
| Joint
| Joint
|
| Nuclear-Detector
| Nuclear detector
|
| Packer
| Packer
|
| Pad
| Pad
|
| Panel
| Panel
|
| Positioning
| Positioning device
|
| Printer
| Printer
|
| Radioactive-Source
| Radioactive source
|
| Shield
| Source shield
|
| Simulator
| Simulation equipment
|
| Skid
| Skid
|
| Sonde
| Sonde
|
| Spacer
| Spacer
|
| Standoff
| Standoff
|
| System
| Processor system
|
| Tool
| Tool
|
| Tool-Module
| Tool module
|
| Transducer
| Transducer
|
| Vibration-Source
| Vibration source
| |
- 4.The Serial-Number Attribute contains
the serial number of the equipment represented by the current Object.
- 5.The Location Attribute specifies
the general location of the equipment during acquisition.
| LOCATION Attribute Options
| Description
| Logging-System
| Equipment is on or in the logging system unit.
|
| Remote
| Equipment is on the surface away from the rig and logging unit system.
|
| Rig
| Equipment is on the rig.
|
| Well
| Equipment is in the borehole.
| |
- 6.The Height Attribute applies only
to equipment located in the borehole. It specifies the height of
the bottom of the equipment above the Tool Zero Point when the tool
string containing the equipment is vertical. This value is positive
when the equipment bottom is above the Tool Zero Point and is negative
when the equipment bottom is below the Tool Zero Point. There is
normally one piece of equipment for which the height is zero.
- 7.The Length Attribute specifies the
length of the equipment and is typically measured from bottom make
up point to top make up point. It may not apply to surface equipment.
The total length of the tool string may not
equal the sum of the lengths of all the equipment that make up the
tool string, since some equipment may slip over other equipment.
Such "slip-on" equipment includes, for example, standoffs,
centralizers, and excentralizers. Similarly, the height of a piece
of equipment may be independent of the lengths of the equipment
below it.
- 8.The Minimum-Diameter Attribute
applies to equipment used in the borehole. It specifies a minimum
outer diameter of the equipment. This is defined to be the minimum
horizontal cross-sectional diameter measured when the equipment
is in a vertical configuration. For extendible or compressible
equipment (e.g., caliper arms and centralizers), this measurement
indicates the smallest operational diameter possible.
- 9.The Maximum-Diameter Attribute
applies to equipment used in the borehole. It specifies a maximum
outer diameter of the equipment. This is defined to be the maximum
horizontal cross-sectional diameter measured when the equipment
is in a vertical configuration. For extendible or compressible
equipment (e.g., caliper arms and centralizers), this measurement
indicates the largest operational diameter possible.
- 10.The Volume Attribute specifies
the volume of the equipment and is typically used to determine bouyant
weight of the equipment. It may not apply to surface equipment.
- 11.The Weight Attribute specifies
the weight of the equipment in air. It may not apply to surface
equipment.
- 12.The Hole-Size Attribute applies
to equipment in the borehole. It specifies the minimum borehole
diameter for which the equipment may reasonably be used.
- 13.The Pressure Attribute indicates
the maximum operational pressure rating of the equipment, when applicable.
- 14.The Temperature Attribute indicates
the maximum operational temperature rating of the equipment, when
applicable.
- 15.The Vertical-Depth, Radial-Drift,
and Angular-Drift Attributes specify the corresponding position
coordinates, relative to the Well Reference Point (see §4.1.8),
of the equipment represented by the current Object. These Attributes
are intended to be used for surface equipment — for example, a geophone
— that is stationary over a period of time. These Attributes may
be updated in a Logical File (see Chapter 6) to permit recording
infrequent or slow changes of position.
Tool Objects
are dictionary-controlled Objects that specify ensembles of equipment
that work together to provide specific measurements or services.
Such combinations are more recognizable to the Consumer than are
their individual pieces. A typical tool consists of a sonde and
a cartridge and possibly some appendages such as centralizers and
spacers.
It is also possible to identify certain pieces or combinations
of surface measuring equipment as tools.
Figure 5-14 defines the Attributes of a Tool
Object.
| TOOL Object Names are dictionary-controlled.
|
| Label
| Restrictions
| Comments
| DESCRIPTION
| C=1, R=ASCII
| -
|
| TRADEMARK-NAME
| C=1, R=ASCII
| 1
|
| GENERIC-NAME
| C=1, R=ASCII
| 2
|
| PARTS
| R=OBNAME
| 3
|
| STATUS
| C=1, R=STATUS
| 4
|
| CHANNELS
| R=OBNAME
| 5
|
| PARAMETERS
| R=OBNAME
| 6
Figure 5-14. Attributes of Tool Object
| |
Comments:
- 1.The TRADEMARK-NAME Attribute specifies
the name used by the Producer to refer to the Tool.
- 2.The GENERIC-NAME Attribute specifies
the name generally used within the industry to refer to tools of
this type.
- 3.ThePARTS Attribute is a List of
references to the Equipment Objects that represent the parts of
the tool.
- 4.The STATUS Attribute indicates whether
the tool is enabled to provide information to the acquisition system
or whether it has been disabled and is simply occupying space.
- 5.The CHANNELS Attribute is a List
of CHANNEL Objects corresponding to Channels that are produced directly
by this Tool. The same CHANNEL Object should not appear in the
CHANNELS Attribute of more than one TOOL Object.
- 6.The PARAMETERS Attribute is a List
of PARAMETER Objects corresponding to Parameters that directly affect
or reflect the operation of this Tool. Certain PARAMETER Objects
may appear in the PARAMETERS Attribute of more than one TOOL Object.
Process
Objects are dictionary-controlled Objects, each of which describes
a specific process or computation applied to input Objects to get
output Objects.
Figure 5-15 defines the Attributes of a Process
Object.
| Label
| Restrictions
| Comments
| DESCRIPTION
| C=1,=(OBNAME, ASCII)
| -
|
| TRADEMARK-NAME
| C=1, R=ASCII
| 1
|
| VERSION
| C=1, R=ASCII
| 2
|
| PROPERTIES
| R=IDENT
| 3
|
| STATUS
| C=1, R=IDENT
| 4
|
| INPUT-CHANNELS
| R=OBNAME
| 5
|
| OUTPUT-CHANNELS
| R=OBNAME
| 6
|
| INPUT-COMPUTATIONS
| R=OBNAME
| 7
|
| OUTPUT-COMPUTATIONS
| R=OBNAME
| 8
|
| PARAMETERS
| R=OBNAME
| 9
|
| COMMENTS
| R=ASCII
| 10
Figure 5-15. Attributes of Process Object
| |
Comments:
- 1.The TRADEMARK-NAME Attribute specifies
the name used by the Producer to refer to the process and its products.
- 2.The VERSION Attribute is the Producer’s
software version of the process.
- 3.The PROPERTIES Attribute is a List
of the properties that apply to the output of the process as a result
of the process. Values for this Attribute are taken from the list
of Properties in Appendix C.
- 4.The STATUS Attribute indicates the
state of the process at the time that the Status Attribute was recorded.
This Attribute is updatable and is typically updated to indicate
when the process is completed or aborted.
| STATUS Attribute Options
| Description
| ABORTED
| The process was aborted.
|
| COMPLETE
| The process was completed.
|
| IN-PROGRESS
| The process is not complete.
| |
- 5.The INPUT-CHANNELS Attribute is
a List of CHANNEL Objects corresponding to Channels that are used
directly by this Process.
- 6.The OUTPUT-CHANNELS Attribute is
a List of CHANNEL Objects corresponding to Channels that are produced
directly by this Process. The same CHANNEL Object should not appear
in the OUTPUT-CHANNELS Attribute of more than one PROCESS Object.
- 7.The INPUT-COMPUTATIONS Attribute
is a List of COMPUTATION Objects corresponding to Computations that
are used directly by this Process.
- 8.The OUTPUT-COMPUTATIONS Attribute
is a List of COMPUTATION Objects corresponding to Computations that
are produced directly by this Process. The same COMPUTATION Object
should not appear in the OUTPUT-COMPUTATIONS Attribute of more than
one PROCESS Object.
- 9.The PARAMETERS Attribute is a List
of PARAMETER Objects corresponding to Parameters that are used by
the Process or that directly affect the operation of the Process.
Certain PARAMETER Objects may appear in the PARAMETERS Attribute
of more than one PROCESS Object.
- 10.The COMMENTS Attribute contains
information specific to the particular execution of the process
(generally provided by the user).
Computation
Objects are dictionary-controlled Objects that contain results of
computations that are more appropriately expressed as
Static Information
rather than as Channels. Computation Objects are similar to Parameter
Objects, except that Computation Objects may be associated with
Property Indicators, and Computation Objects may be the output of
PROCESS Objects (see §5.8.5).
Figure 5-16 defines the Attributes of a Computation
Object.
Figure 5-16. Attributes of Computation Object
Comments:
- 1.The Properties Attribute is a List
of Property Indicators (see Appendix C). The Property Indicators
summarize the characteristics of the Computation and the processing
that has occurred to produce it.
- 2.The Dimension Attribute specifies
the array structure of a single value of the current Computation
(see §4.4.4).
- 3.The Zones Attribute references a
List of Zone Objects that specify mutually disjoint intervals over
which the value of the current Computation is constant. A Computation
may have different values in different zones. When this Attribute
is present, the Computation is said to be Zoned, and it is considered
to be defined only in the zones specified by the Zones Attribute.
It is considered to be undefined elsewhere.
The Zone Objects referenced in this List
must all have the same Domain Attribute Value. That is, a Computation
Object may only be zoned over a single domain.
The Zones Attribute may be absent, in which
case the Computation is said to be Unzoned. In this case, the Computation
is considered to be defined everywhere.
- 4.The Values Attribute is a List of
Computation values corresponding to the zones listed in the Zones
Attribute. When the Computation is Zoned, the number of Computation
values is the same as the number of zones referenced, and the
kth Computation value applies to the kth zone.
When the Computation is Unzoned, there
is a single Computation value in the Values Attribute.
The Count of the Values Attribute is equal
to the number of Computation values listed (equal to 1 if Unzoned
or determined by the Count of the Zones Attribute if Zoned) multiplied
by the size in elements of each value (determined by the Dimension
Attribute). For example, if there are three zones, and if Dimension
= {3, 4, 128}, then there are three Computation values listed, each
1,536 elements big, making the Count of the Values Attribute equal
to 3*1,536 = 4,608.
- 5.The SOURCE Attribute is a reference
to another Object that describes the immediate source of the Computation,
for example, a PROCESS Object.
The most common method of calibration is the computation
Calibrated Channel = Gain * Uncalibrated Channel
+ Offset,
where the coefficients "Gain" and "Offset"
are computed from two measurements (Zero and Plus) of the Uncalibrated
Channel and their two corresponding references. Such a calibration
is acceptable provided that the measurements are within a certain
tolerance of the references and the coefficients are within a certain
tolerance of their nominal values, e.g., Gain = 1 and Offset = 0.
This method of calibration is not universal,
and as measuring systems become more complex the method of calibration
becomes more complex. Nevertheless, a number of interesting calibration
models, although computationally distinct from the model shown above,
use the same basic types of information:
- Uncalibrated Channel measurements
- Measurement references
- Measurement tolerances
- Computed calibration coefficients
- Nominal (or reference) coefficient values
- Coefficient tolerances
The Objects defined in the next two sections
support the recording of a particular generalization of the information
listed above.
Calibration-Measurement
Objects record measurements, references, and tolerances used to
compute calibration coefficients.
Figure 5-17 defines the Attributes of a Calibration-Measurement
Object. Calibration-Measurement Object Names are arbitrary.
Figure 5-17. Attributes of Calibration-Measurement Object
Comments:
- 1.The PHASE Attribute
is a dictionary-controlled
code indicating what phase in the overall job sequence is represented
by the current measurement.
| PHASE Attribute Options
| Description
| AFTER
| After survey calibration.
|
| BEFORE
| Before survey calibration.
|
| MASTER
| Master calibration.
| |
- 2.The Measurement-Source Attribute
references an Object that specifies the source of the data recorded
in the Measurement Attribute.
- 3.The Type Attribute defines the type
of measurement taken. Values of this Attribute are dictionary-controlled
terms. For the simple model described earlier, the Type is "Zero"
or "Plus".
- 4.The Dimension Attribute specifies
the array structure of samples recorded in the Measurement Attribute,
of the Reference Attribute, of the Maximum-Deviation Attribute,
of the Standard-Deviation Attribute, of the Standard Attribute,
of the Plus-Tolerance Attribute, and of the Minus-Tolerance Attribute
(see §4.4.4).
- 5.The Measurement Attribute is a measurement,
possibly containing many samples, related to the uncalibrated data
and described by the Type Attribute. The measurement may represent
values of, an average of, or some other function of the uncalibrated
data.
- 6.The Sample-Count Attribute is the
number of samples used to compute the Maximum-Deviation and Standard-Deviation.
- 7.The Maximum-Deviation Attribute
is meaningful only when the Measurement Attribute contains a single
sample. In this case, the measurement is considered to be a mean,
and Maximum-Deviation represents the maximum deviation from this
mean of any sample used to compute the mean. For array samples,
the mean and maximum deviation are computed independently for each
sample Element. The deviation for any Element from the mean is
computed as an absolute value.
- 8.The Standard-Deviation Attribute
is meaningful only when the Measurement Attribute contains a single
sample. In this case, the measurement is considered to be a mean,
and Standard-Deviation represents the statistical standard deviation
of the samples used to compute the mean. For array samples, the
mean and standard deviation are computed independently for each
sample Element.
- 9.The Begin-Time Attribute is the
time at which acquisition of the measurement in the Measurement
Attribute began. The Value of this Attribute represents either
an absolute date and time (if using Representation Code DTIME) or
an elapsed time from the file creation time specified by the Creation-Time
Attribute of the Origin Object.
- 10.The Duration Attribute is a time
interval representing the acquisition duration of the measurement
in the Measurement Attribute.
- 11.The Reference Attribute is the
expected nominal value of a single sample of the measurement represented
in the Measurement Attribute.
- 12.The Standard Attribute is the measurable
quantity of the calibration standard used to produce the Value of
the Measurement Attribute. For example, a standard used to calibrate
a caliper is a steel ring. Its measurable quantity is its inside
diameter, say 8 inches. The Measurement and Reference Attributes
may represent the same physical quantity as the calibration standard,
e.g., length. In this case, the Standard provides the same information
as the Reference and is normally absent to avoid redundancy. It
is possible, however, for the Measurement and Reference Attributes
to represent a different physical quantity, say voltage. In this
case, the Standard Attribute is required to describe the transformation
from the physical quantity represented by the Measurement and Reference
Attributes to the physical quantity of the calibration standard,
e.g., from millivolts to inches. Deriving this transformation may
require the Values of the Standard Attributes from more than one
Calibration-Measurement Object.
- 13.The Plus-Tolerance Attribute indicates
by how much each measurement sample may exceed a reference and still
be "within tolerance". Elements of this Attribute are
all non-negative numbers. If a measurement sample is an array,
then so is its reference and plus tolerance. The convention that
a measurement sample be within tolerance is that each element of
the measurement sample array be less than or equal to the sum of
the corresponding reference and plus tolerance array elements.
The plus tolerance represents in some sense
the maximum acceptable drift of each recorded measurement sample
above the value of the recorded reference. If the Plus-Tolerance
Attribute is absent, then the plus tolerance is implicitly infinite.
For the common simple case when a measurement
sample is scalar, the sample value 352 is within tolerance when
its reference is 350 and its plus tolerance is 5. It is out of
tolerance when its reference is 300 and its plus tolerance is 50.
- 14.The Minus-Tolerance Attribute indicates
by how much each measurement sample may fall below a reference and
still be "within tolerance". Elements of this Attribute
are all non-negative numbers. If a measurement sample is an array,
then so is its reference and minus tolerance. The convention that
a measurement sample be within tolerance is that each element of
the measurement sample array be greater than or equal to the difference
of the corresponding reference and minus tolerance array elements.
The minus tolerance represents in some sense
the maximum acceptable drift of each recorded measurement sample
below the value of the recorded reference. If the Minus-Tolerance
Attribute is absent, then the minus tolerance is implicitly infinite.
For the common simple case when a measurement
sample is scalar, the sample value 348 is within tolerance when
its reference is 350 and its minus tolerance is 5. It is out of
tolerance when its reference is 400 and its minus tolerance is 50.
Calibration-Coefficient
Objects record coefficients, their references, and tolerances used
in the calibration of Channels.
Figure 5-18 defines the Attributes of a Calibration-Coefficient
Object. Calibration-Coefficient Object Names are arbitrary.
Figure 5-18. Attributes of Calibration-Coefficient Object
Comments:
- 1.The Label Attribute specifies a
label for the coefficients that identifying their role in the calibration
process. Values of this Attribute are dictionary-controlled terms.
For the simple model described earlier, the Label is "Gain"
or "Offset".
- 2.The CoefficientS Attribute are coefficients
corresponding to the label in the Label Attribute.
- 3.The ReferenceS Attribute are references
corresponding to the coefficients in the CoefficientS Attribute.
Each recorded reference represents in some sense the nominal value
of the corresponding recorded coefficient.
- 4.The Plus-Tolerances Attribute are
values that indicate by how much a coefficient may exceed a reference
and still be "within tolerance". Elements of this Attribute
are all non-negative numbers. The convention that a coefficient
be within tolerance is that it be less than or equal to the sum
of the corresponding reference and plus tolerance.
The recorded plus tolerance represents in
some sense the maximum acceptable range of the recorded coefficient
above the value of the recorded reference. If the Plus-Tolerances
Attribute is absent, then plus tolerance is implicitly infinite.
For the simple case illustrated earlier,
a Gain of 1.05 is within tolerance when its reference is 1.0 and
its plus tolerance is 0.1. It is out of tolerance when its reference
is 1.0 and its plus tolerance is 0.01.
- 5.The Minus-Tolerances Attribute are
values that indicate by how much a coefficient may fall short of
a reference and still be "within tolerance". Elements
of this Attribute are all non-negative numbers. The convention
that a coefficient be within tolerance is that it be greater than
or equal to the difference of the corresponding reference and minus
tolerance.
The recorded minus tolerance represents in
some sense the maximum acceptable range of the recorded coefficient
below the value of the recorded reference. If the Minus-Tolerances
Attribute is absent, then minus tolerance is implicitly infinite.
For the simple case illustrated earlier,
a Gain of .95 is within tolerance when its reference is 1.0 and
its minus tolerance is 0.1. It is out of tolerance when its reference
is 1.0 and its minus tolerance is 0.01.
NOTE: The coefficients, references, plus-tolerances,
and minus-tolerances Attributes must all have the same Count.
Calibration
Objects identify the collection of measurements and coefficients
that participate in the calibration of a Channel.
Figure 5-19 defines the Attributes of a Calibration
Object. Calibration Object Names are arbitrary.
Figure 5-19. Attributes of Calibration Object
Comments:
- 1.The Calibrated-Channels Attribute
is a List of references to Channel Objects. The corresponding Channels
(typically just one) are declared to be calibrated using the coefficients
and measurements identified by the Coefficients and Measurements
Attributes described below.
- 2.The Uncalibrated-Channels Attribute
is a List of references to Channel Objects. The corresponding Channels
(typically just one) are used, along with coefficients and according
to the computational method, to compute the Channels identified
by the Calibrated-Channels Attribute.
- 3.The Coefficients Attribute is a
List of references to Calibration-Coefficient Objects. The coefficients,
references, and tolerances collectively defined by these Objects
are used to compute the Channels identified by the Calibrated-Channels
Attribute.
- 4.The Measurements Attribute is a
List of references to Calibration-Measurement Objects. The measurements
collectively defined by these Objects are used to derive the coefficients
that are used to calibrate the Channels identified by the Calibrated-Channels
Attribute.
- 5.The Parameters Attribute is a List
of references to Parameter Objects. The referenced Objects provide
information directly associated with the calibration process, for
example statistics, quality control indicators, parameters entered
by the operator, vendor-supplied coefficients, and other information
(numeric or textual) that is potentially of interest to the Consumer.
- 6.The Method Attribute defines the
computational method used to calibrate the Channels identified by
the Calibrated-Channels Attribute. Values of this Attribute are
dictionary-controlled terms. For the simple model described earlier,
the Method might be "Two-Point-Linear".
Group Objects
indicate logical groupings of other Objects. The use of Group Objects
is completely at the discretion of the Producer to define whatever
associations are deemed useful.
Figure 5-20 defines the Attributes of a Group
Object. Group Object Names are not dictionary-controlled but usually
are selected to convey some meaning to the Consumer.
Figure 5-20. Attributes of Group Object
Comments:
- 1.
The OBJECT-TYPE Attribute specifies
the Type of Object that is referenced in the Object-List Attribute.
This Attribute is ignored whenever the OBJECT-LIST Attribute has
Representation Code OBJREF.
- 2.
The OBJECT-LIST Attribute is a List
of references to arbitrary Objects when its Representation Code
is OBJREF. Otherwise, it is a List references to Objects of the
Type specified in the Object-Type Attribute. These Objects are
considered to be related in some fashion known to the Producer.
- 3.
The GROUP-LIST Attribute is a List
of references to other Group Objects. The Group Objects referenced
are completely arbitrary and may even specify Object Types different
from that specified in the the current OBJECT-TYPE Attribute.
Splice Objects
describe the process of concatenating two or more instances of a
Channel (e.g., from different runs) to get a resultant spliced
Channel.
Figure 5-21 defines the Attributes of a Splice
Object.
| Lable
| Restrictions
| Comments
| OUTPUT-CHANNELS
| C=1, R=OBNAME
| 1
|
| INPUT-CHANNELS
| R=OBNAME
| 2
|
| ZONES
| R=OBNAME
| 3
Figure 5-21. Attributes of Splice Object
| |
Comments:
- 1.The Output-Channel Attribute references
the Channel Object that represents the spliced Channel, i.e., the
resultant of the splice operation. The spliced Channel may be implied
by the Splice Object and need not actually exist. When the spliced
Channel does exist, its Properties Attribute must include the "Spliced"
flag.
- 2.The Input-Channels Attribute is
a List of references to Channel Objects that represent the input
Channels of the splice operation.
- 3.The Zones Attribute is a List of
references to Zone Objects. When not Absent, this Attribute must
have the same number of Elements — i.e., the same Count — as the
Input-Channels Attribute. The kth
referenced Zone Object defines a zone in which
the spliced Channel matches the values of the kth
referenced input Channel
(allowing for possible differences in Representation Code and Units).
The referenced Zone Objects must specify mutually-disjoint zones
in the same domain, but the ordering of the zones is arbitrary.
When the ZONES Attribute is Absent, changes
in the input Channel are indicated by Updates (see Appendix D).
Unformatted
Data Logical Records are Indirectly Formatted Logical Records of
Type NOFORM that contain "packets" of unformatted (in
the DLIS sense) binary data. The Data Descriptor reference of the
NOFORM Logical Record refers to a NO-FORMAT Object, defined
in Figure 5-22. The purpose of Unformatted Data Logical Records
is to transport arbitrary data that is of value to the Consumer,
the format of which is known by the Consumer, but which has no DLIS
Semantic meaning.
Unformatted
Data Identifier Logical Records are Explicitly Formatted Logical
Records of Type UDI that contain the single Set Type
NO-FORMAT.
The purpose of Unformatted Data Identifier Logical Records is to
identify data that is recorded in Unformatted Data Logical Records.
5.10.1 No-Format Objects
NO-FORMAT Objects identify packet sequences of
unformatted binary data.
The Indirectly Formatted Data field of each NOFORM IFLR that references
a given No-Format Object contains a segment of the source stream
of unformatted data. This source stream is recovered by concatenating
these segments in the same order in which they occur in the NOFORM
IFLRs. Each segment of the source stream is considered under the
DLIS to be a sequence of bytes, and no conversion is applied to
the bytes as they are placed into the IFLRs nor as they are removed
from the IFLRs.
Figure 5-22 defines the Attributes of a No-Format Object.
Figure 5-22. Attributes of No-Format Object
Comments:
- 1.The CONSUMER-NAME Attribute is a
client-provided name for the data, for example an external file
specification.
5.11 End of Data Logical Records (EOD)
End of Data
Logical Records are Indirectly Formatted Logical Records of Type
EOD that signify the end of a given sequence of IFLRs. It is useful
for the Consumer to know when a sequence of IFLRs ends, particularly
when more data, either Static or Dynamic, follows in the Logical
File.
The Data Descriptor Reference of an EOD IFLR
is a copy of the Data Descriptor Reference of the sequence of IFLRs
that is to be indicated ended. The Indirectly Formatted Data of
the EOD IFLR consists of a single value (Representation Code USHORT)
that contains the Logical Record Type of the sequence of IFLRs that
has ended.
To illustrate this, let "A" and "B"
represent two distinct Data Descriptor Reference values. The IFLRs
might occur in a Logical File in the following fashion:
{FDATA, A, data ... }
{FDATA, A, data ... }
{NOFORM, B, data ... }
{NOFORM, B, data ... }
• • •
{NOFORM, B, data ... }
{EOD, B NOFORM} end of NOFORM sequence "B"
{FDATA, A, data ... }
• • •
{EOD, A, FDATA} end of FDATA sequence "A"
