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ICAS version control

the most recent date of version activity is:

AAT ICAS version 8.02 Basilicum as of UCN 12019 U08 White

before referencing an effective version of AAT ICAS, read the most recent version declaration notes.


AAT ICAS process review

AAT is strongly committed to improving an already highly advanced state of the art for ICAS (Integrated Chronological Applications System). AAT has made some steps to facilitate a transfer of ICAS standards, at no charge, to a variety of standards developing organizations toward development of any common standards initiatives. should standards developing organizations elect to develop or specify ICAS or other similar standards, AAT is committed to cooperate for purposes related to the harmonization of ICAS or other similar standards.

AAT ICAS work toward reviewing areas of the International System of Units (SI) is outlined in AAT ICAS 0600.

additional cross-disciplinary and inter-organizational review of strategies for ICAS optimization is encouraged, and AAT reviews comments and reviews about ICAS and ICAS standards on an ongoing basis. please see AAT ICAS 1001, 0600, 2001, 3001, 9001, and the sections below for current information.

AAT ICAS is preparing for co-review with for purposes of harmonizing ICAS and TimeML (Markup Language for Temporal and Event Expressions) specifications. information about an XML formulation of ICAS was posted on the LINGUIST discussion. please see TimeML and Basilicum AAT ICAS 3030 for additional information.

some recent highlights

principles of formatting for improved information interchange provide a strong rationale for the designation of Interform format ordering as a preferred convention of usage for ICAS scales of calendar and clock. (AAT ICAS 2021)

although IDC definitions for a "decimal prefix-submultiple were devised in extension to the metric prefixes specified by SI, these submultiples of the IDC main unit more closely approximate the SI fixed-second in the terms of a widely referenced measure of a coordinated day that can also be expressed in fixed unit terms." (AAT ICAS 2023).

a symbol form for the tikochron is used to designate ICAS time-derived measures in the terms of IDC in a manner that is counterpart (similar in dimension yet different in magnitude) to those measures that have been designated in terms of the SI second. (AAT ICAS 2023)


AAT process review of ICAS standards

some other issues relating to the development of a possible future version of ICAS standards include the following:

a very good way for those interested in information about ICAS development or in participating in ICAS process review is to sign up for the aaticas egroup on yahoogroups. there is no charge however participants must first be registered with yahoogroups and then sign up for the aaticas egroup discussion. or let us know about ICAS discussions in other fora.

ICAS standards update

the AAT ICAS standards documents are expected to be revised in the next months.

the version identifier is expected to remain 'Basilicum' as no changes are expected that would affect compatibility with the current 'Basilicum' standards.

as the general organization of the standards has served a variety of different applications or projects for the organization of ICAS concepts, the general organization is expected to remain the same, with little if any changes to the document names.

however the file extensions are expected to change from 'html' to 'xht'.


process review of timeserver domain specifier

AAT shall review interest in the establishment of a domain-name convention for time-server information: a single letter 't' for time or timeserver. the convention would accommodate a very convenient way for people to check timeservers, or for applications to reference Internet timeservers.

web servers could be configured to automatically map a 't' request to designated timeservers (for example,, and so forth.).


process review of decimal calendar module

AAT review of a decimal calendar module currently centers on the following considerations:

AAT is also reviewing the usability of a decimal calendar module as an alternative method of specifying calendar dates for particular applications.


AAT process review of ICAS version control

effective versions of ICAS are designated by AAT after a comprehensive process review to ensure conformance with ICAS administrative objectives. process review should allow for a public review so that any parties to a version may comment on issues of consideration. Process review should also determine issues of rights-management related to ICAS version changes.

issues concerning the rights of users and other parties encompass the deprecation of prior ICAS features, and the use of ICAS with regard to uses of other systems of measure. AAT considers comments from ICAS licensees and from the public in determining rights issues with regard to ICAS and ICAS version control. AAT considers that the voluntary use of an emerging ICAS standard does not abrogate the rights of other parties to other systems of measure. AAT also considers that the ICAS standard itself does not abrogate the rights of other parties. AAT strives to accommodate the appropriate transfer of ICAS standards to other interested parties for purposes of facilitating coordination with other standards and practices.

in the view of the AAT ICAS department, AAT ICAS Basilicum should be considered as deprecating non-essential features of prior versions of ICAS. all registered and non-registered users or other interested parties must update to an effective version of ICAS.


AAT process review of ICAS language support

please see AAT ICAS 3005 for a current standard note on language support.

AAT has determined a demand for ICAS language support in French, German, Dutch, Spanish, Basque, Portuguese, Italian, Greek, Russian, Turkish, Arabic, Hebrew, Korean, Laotian, Chinese, Japanese, and other languages.

new development in translations about topics ICAS

a wiki article on the topic of Decimal_time at includes information about AAT ICAS.

AAT ICAS at has reviewed the content of the English source of PARAGRAPH02 of the Decimal_time wiki and can thus readily approve of the content of the English source with reference to AAT ICAS standards. and links to the various languages are also noted:

decimal time wiki (

AAT ICAS believes that the information documented in the wiki (and specifically including PARAGRAPH02) is critical to understanding and using concepts of decimal time, both established and contemporary. (and AAT also concurs with the choice of this content as significant for concepts that can be important for translation). AAT ICAS moreover stands by some higher ICAS standards of information quality with reference to administering a topic of decimal time.

special thanks from AAT to WorldLingo Translations for making this information about Decimal_time more accessible to more readers!


AAT process review of ICAS licensing

standards should be developed so that issues of ICAS compliance can be determined by ICAS users with minimal administration by AAT ICAS.

public use licensing for ICAS shall remain available for no fee for any subsequent versions of ICAS.

the availability of particular categories of developer licensing is subject to change.

AAT ICAS has determined that administration of localization licensing for most cases may be able to be administered for the present $1000 USD fee; however certain cases may require additional fees.


AAT process review of ICAS conformance

developments of levels of ICAS conformance remain under consideration. possible levels of conformance may concern specifications of support for the use of multiple scales, for migrating systems to uses of ICAS, or for uses of ICAS as a primary scalar system. levels of conformance can be part of a plan for the design of metrication policies and programs.

with careful planning and project management, the ides of March, Y2K bug, and the like can be avoided. but don't rely on too simple of a plan.

'the ides of March are present, and not yet gone'—Plutarch, omens, Julius Caesar

everything should be as simple as possible, but not simpler—Albert Einstein

good programming tip: the false statement "10 degrees Fahrenheit is 10 degrees Celsius" can be corrected with reference to good programming practices described in the Webmonkey Advanced JavaScript Tutorial by Thau.


AAT process review of retrospect program

the AAT technology timeline has developed from an aatideas program reference into one of the more popular areas on the aatideas web site. AAT is thus reviewing more formal program criteria for this comprehensive overview of several technologies.

please see the AAT guide to timelines pdf document and the timeline compilation notes for additional information.


acknowledgements in development of ICAS

acknowledgments relating to the development of certain time metrication standards or technologies are credited to Bureau International des Poids et Mesures (BIPM), International Standards Organization (ISO), World Wide Web Consortium (W3C), National Radio Astronomy Observatory (NRAO),, UK Metric Association (UKMA), United States Naval Observatory (USNO), Physikalisch-Technischen Bundesanstalt, United States Metric Association, (USMA), Inc., AAVSO, American Society of Civil Engineers, California Department of Transportation, Software Engineering Institute of Carnegie Mellon University, Lawrence Berkeley Laboratory, QuEST Forum, Smithsonian Institution, State of New York,, United States Department of Commerce, United States National Institute of Standards and Technology, United States Nuclear Regulatory Commission, the Society for Technical Communication and many of its special interest groups, Usability Professionals' Association, John P. Sumner, Kate DeVries Smith, Patricia Backer, Dean Barker, Michael Bennett, Michael Bennett, Marcus Berger, Russell A. Berman, Bert Bos, Joe Brandt, Dennis Brownridge, José Castaňo, Marie-Ange Cotteret, Ruth Clark, David Day, David Dick, Stan Doore, Susan M. Dray, Jim Elwell, Cesare Emiliani, Michele Ferretti, Lisa Ferro, James R. Frysinger, Robert Gaizauskas, B. Guinot, Yvonne Halpaus, Patrick Hanks, Geoff Hart, Bill Hooper, Stephen Humphreys, Robert Ingria, Ahren W. Johnston, Lyle Kantrovich, Graham Katz, Robert Knippen, John R. Kohl, Markus Kuhn, Marcia Lazo, Simone Leonardi, Sigfrido Leschiutta, Elizabeth Leyva, Jessica Littman, Zhengjie Liu, Sal Mangano, Inderjeet Mani, Michael H. Markel, Mary Martinson, Chris Mastrangelo, Gene Mechtly, Adam Meyers, Pat Naughtin, Donald A. Norman, Martha Palmer, Shlomo Perets, Raymond Petry, James Pustejovsky, Whitney Quesenbery, Madan R., Dragomir Radev, Robert L. Ragot, Joseph B. Reid, Nick Rosenthal, Roser Saurí, Barry Schiffman, Helene Schultz, Andrew See, P. K. Seidelmann, Andrea Setzer, Terry Simpson, David G. Skoglund, Larry Stark, Beth Sundheim, Barry N. Taylor, Anders J. Thor, Claus Tondering, Edward Tufte, Tom Wade, John M. Ward, John Ward, Richard E. White III, Gerhard Uhde, Marc Verhagen, Brij Bhushan Vij, Katie Ware, Ray Winstead, John Woelflein, AppleScript developers communities, Java developers communities, Apple Computer, Microsoft Corporation, Sun Microsystems, Holland Herald, National Geographic, South African Metrication News,, and others in the communities in which standards are used and developed. acknowledgements relating to the development of certain time metrication standards or technologies does not imply an endorsement of ICAS. acknowledgments compiled by ICAS principal research editor Ronald L Stone.

top document updated:

system identifiersdatetime
Uniform CalendarUCUCN 12019 U08 White
Inter-Dial ClockIDCzone(UT)t937 tt962
'ICAS in use' can accommodate calendar and clock formatting 'for all people, for all time'.
day of yearD-o-YAD common year day188
Gregorian calendarGG2019 July 07 Sunday
seconds, minutes, hoursSMHUT23:30:40
style legend


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