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Decision
#1: Deliverable options
Destination
system constraints on form
Interim
dual deliverables
Decision
#2: Forms options
Composed
documents
Processable files
CITIS
interactive access
Decision
#3: Specification and standard options
Composed
documents
Specifications
and standards for graphics
Specifications
for vector graphics
Processable
text
Decision
#4: Digital delivery mode options
Magnetic
tape
Floppy
Disk
Optical
Disk
Digital
deliverable summary
Example
- Delivery of digital data as processable files
Digital delivery options for technical manuals are not mutually exclusive.
There will often be cases when several options will be combined for specific
deliverables during a defence system acquisition. The decision criteria
presented in this handbook are intended to aid in selecting the best
options. The following is guidance for applying the criteria to technical
manuals.
Decision
#1: Deliverable options
Technical manual data can be delivered as composed documents, processable files, or interactive access to the CITIS database. The composed document deliverable option offers the least flexibility, even in digital form. It is a static, formatted presentation of the manual, which can only be archived, viewed, and printed after receipt.
Processable files, on the other hand, offer more robust capabilities. These files can be updated or transformed into many different data types. With appropriate data processing systems, processable files can support creation of job guides, training documents, and eventual on-line distribution of selected portions of the data to maintenance personnel. In addition, a separate indexing mechanism may be needed for either machine or human search or access.
Destination
system constraints on form
Processable data files are preferable to composed documents, but the presence of both text and graphics may cause some difficulty because not all presently installed computing equipment and software can simultaneously process text and embedded graphics. This issue is rapidly disappearing. Nonetheless, during the period of intended use, installed hardware and software at both the contractor's site (i.e., the source system) and the user's site (i.e., the destination system) will be the deciding factor as to which form the deliverable may take.
Requirements for technical manual deliverables may include both composed documents in digital form and processable data files. However, until more advanced user systems are available, it may be necessary to accept a hard copy (paper) technical manual for approval, reproduction, and distribution, and a digital form of the manual for archiving or update and maintenance.
When NATO/NATO nations implement more advanced computer systems, processable technical manual files (with or without composed document image files of the technical manual) should suffice.
A technical manual is made up of both text (including narrative and tables) and graphics. Integrating these elements into a complete technical manual and dealing with user requirements that are different for interim review and approval than for final delivery may require more than merely choosing a single optimum form. The project manager may have to choose the appropriate forms for multiple deliverables (e.g., a document data file consisting of PDL to support in-process reviews, and processable data files for the final deliverable).
If composed documents have been selected at decision #1, the forms for technical manual delivery can be either hard copy (paper or microfilm) or a digital composed document image file. The digital form of this deliverable consists of composed page images of the full manual. Two examples of digital composed document files are PDL and raster.
These options offer greater advantages than hard copy in storage, distribution, viewing, and printing. They also provide slightly more flexibility than hard copy with respect to future data uses, although their formats will be fixed and unyielding. PDL and raster provide a two-dimensional image of each manual page, offering no further updating or processing features beyond replication. Both hard copy and the digital forms of composed documents complicate update and maintenance.
If processable files are selected at decision #1, the forms for technical manual delivery can be either one or more sets of text and graphics files, or an integrated data file that contains text and graphics in a compound data architecture. A particular type of integrated data file is the IETM
Computer screen display is the primary, preferred form for CITIS information delivery.
Decision
#3: Specification and standard options
Technical manuals acquired as composed documents may be acquired in the form of either camera-ready masters or digital document image files. The intended application may also require an additional indexing mechanism for efficient subsequent processing. Camera-ready masters should be delivered in accordance with appropriate standard. Digital document image files in raster form should be acquired in accordance with MIL-R-28002. Conversion systems for paper copy are in place for converting legacy data to the MIL-R-28002 format. MIL-R-28002 provides two options: Type I and Type II. Type I raster graphics binary format consists of Group 4 encoding as defined in FIPS PUB 150(Consultative Committee on International Telegraphy and Telephony (CCITT) Recommendation T.6). Type II raster graphics binary format consists of ASN.1 and CCITT Recommendation T.6 encoding as specified by the document description presented in the NIST ODA Raster Document Application Profile.
The term "tiled raster data" refers to drawings that are segmented into several grids of small blocks containing raster data. These blocks of data are compressed individually. Modifications to a tiled drawing are easier to control since only those small blocks of data requiring changes are modified. Storage of document images in a PDL such as PostScript provides an alternative form. PDL document image files can be acquired as interim deliverables, or as final deliverables in addition to (but not in place of) processable data files using MIL-STD-1840 and MIL-M-28001.
Specifications
and standards for graphics
Graphics data may be in either raster or vector formats. Assuming an adequate scanning resolution, raster provides nearly exact fidelity for illustrations. Vector graphics translates data between different sending and receiving systems in native forms (this can introduce errors, even when an intermediate, neutral format is agreed on).
For example, a line expressed as a series of pixels connecting a pair of end points, versus a line expressed as an origin, direction, and length. Vector representations are easily edited, maintained, and updated. Vector representations also generally have the advantage of much smaller file size, even when the raster bit-map image has been compressed using an algorithm such as that specified by MIL-R-28002.
Nevertheless, raster graphic illustrations are frequently encountered because scanning remains the only practical way of converting a legacy of hardcopy drawings into digital data. Despite the quality limitations of raster data, the hardcopy legacy data requires supporting both raster and vector formats for graphics.
Specifications
for vector graphics.
There are two choices of standards to consider for vector graphics:
- MIL-D-28003 for CGM
- MIL-D-28000 for IGES.
For technical manuals, CGM is the preferred option but IGES can be used. Extensions to the standard to allow translations of native CAD data into CGM are still being developed. If technical manual illustrations are being derived directly from design data, then system limitations may constrain the choice of delivery standard. In selecting the appropriate option, the project manager should recognize the potential problems created by multiple translation steps (e.g., unique CAD system to IGES to CGM). MIL-D-28003 specifies an Application Profile (AP) with two options: Level I for publication quality data, and Level II for draft quality data.
Uncompressed raster data can be included in a CGM file, but MIL-D-28003 should only be used where the predominant form of the graphics information is vector. When IGES is used for technical manual illustrations, the Class I Technical Illustration subset is appropriate. Data would be delivered in ASCII, as specified by MIL-D-28000.
Processable text data files should be acquired in accordance with MIL-M-28001, which implements the SGML. An SGML Document Type Definition (DTD) and Formatting Output Specification Instance (FOSI) created in accordance with the provisions of MIL-M-28001 or AECMA 1000 D should be used to meet the document structure and format requirements of the technical manual. The project manager may be required to fund development of a unique DTD or FOSI. A more sensible approach would be to make use of previously developed DTDs and FOSIs that reside in a reuse library.
Decision
#4: Digital delivery mode options
Physical media is currently the only economical option for the delivery of large document image files or processable data files. While telecommunications bulk transfer of these files may be possible, it is usually not an economical option because of the large volume of data contained in these files, particularly the raster document image and raster graphics files.
When CITIS interactive access to a contractor's technical manual database is chosen, then telecommunications are warranted as a delivery mode for deliverables. Security aspects will also affect the selection of delivery method.
The standard physical media option is magnetic tape. The mature, stable, non proprietary standard which MIL-STD-1840 requires for magnetic tape supports most originating and destination systems.
The preferred physical media option for small files is 3.5 inch, 1.44 megabyte floppy disk. Like magnetic tape, floppy disk is a mature, stable technology that is usually available at all sending and destination systems.
Optical disk or CD-ROM will be alternative physical media options in the future, and are generally well suited for data archiving because they can accommodate very large volumes of data quite efficiently.
Selection of the options at each node of the Technical Manuals decision template should be aligned to the needs of the organizations responsible for technical manual publication and maintenance within each military department.
However, requirements for interim deliverables that are provided only for review and approval (verification) may be evaluated differently than are requirements for final deliverables. Delivery of processable data is less important when the principal applications are view and annotate, than when the intended applications are update/maintain and process/transform. Consequently, document image files may be more appropriate early in the life cycle of the program; however, processable data files should be the deliverable of choice when the Government assumes the responsibility for technical manual update and maintenance.
Example
- Delivery of digital data as processable files
Selection options for technical manuals may be processable technical manual files composed of:
- SGML text files in accordance with MIL-M-28001 and MIL-STD-1840,
- Raster graphics files in accordance with MIL-R-28002, Type I and MIL-STD-1840, and
- Vector graphics files in accordance with MIL-D-28003 and MIL-STD-1840.
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10/4/2000 10:16:28 AM by TK Copyright© 1999-2010 LAMP / IDE Virtual Enterprise |