Specialized Color Function for Display of Signed Data

This Mathematica script defines a color function to be used with Mathematica’s plotting modules for differentiating data attaining both positive and negative values. Positive values are shown as shades of blue, and negative values are shown in red. The intensity of the color reflects the absolute value of the data value.

Posted in: Briefs, Information Sciences, Mathematical models, Displays, Identification


Spatial and Temporal Low-Dimensional Models for Fluid Flow

A document discusses work that obtains a low-dimensional model that captures both temporal and spatial flow by constructing spatial and temporal four-mode models for two classic flow problems. The models are based on the proper orthogonal decomposition at two reference Reynolds numbers. Model predictions are made at an intermediate Reynolds number and compared with direct numerical simulation results at the new Reynolds number.

Posted in: Briefs, TSP, Information Sciences


Converting From DDOR SASF to APF

A computer program called “ddor_sasf2apf” converts delta-door (delta differential one-way range) request from an SASF (spacecraft activity sequence file) format to an APF (apgen plan file) format for use in the Mars Reconnaissance Orbiter (MRO) mission-planning-and- sequencing process. The APF is used as an input to “APGEN/AUTOGEN” in the MRO activity- planning and command-sequence-generating process to sequence the delta-door (DDOR) activity. The DDOR activity is a spacecraft tracking technique for determining spacecraft location.

Posted in: Briefs, Information Sciences, Communication protocols, Computer software and hardware, Surveillance, Spacecraft


Converting From CVF to AAF

A computer program called “dsn config converter” automates what had been a manual process for updating the multi-mission adaptation file (multi.aaf) used by a multiple- mission- command- sequence- generating process comprised of a combination of the AUTOGEN and APGEN programs mentioned in the immediately preceding article. The program converts the dsn_config.cvf file that provides DSN (Deep Space Network) antenna configuration code mappings from a context variable file (CVF) format used in another part of the command generation process to an APGEN activity file (AAF) format used by AUTOGEN and APGEN.

Posted in: Briefs, Information Sciences, Communication protocols, Computer software and hardware, Flight management systems, Automation


Documenting AUTOGEN and APGEN Model Files

A computer program called “autogen hypertext map generator” satisfies a need for documenting and assisting in visualization of, and navigation through, model files used in the AUTOGEN and APGEN software mentioned in the two immediately preceding articles. This program parses autogen script files, autogen model files, PERL scripts, and apgen activity-definition files and produces a hypertext map of the files to aid in the navigation of the model. This program also provides a facility for adding notes and descriptions, beyond what is in the source model represented by the hypertext map. Further, this program provides access to a summary of the model through variable, function, sub routine, activity and resource declarations as well as providing full access to the source model and source code. The use of the tool enables easy access to the declarations and the ability to traverse routines and calls while analyzing the model.

Posted in: Briefs, Information Sciences, Cartography, Computer software and hardware, Human machine interface (HMI)


Sequence History Update Tool

The Sequence History Update Tool performs Web-based sequence statistics archiving for Mars Reconnaissance Orbiter (MRO). Using a single UNIX command, the software takes advantage of sequencing conventions to automatically extract the needed statistics from multiple files. This information is then used to populate a PHP database, which is then seamlessly formatted into a dynamic Web page.

Posted in: Briefs, Information Sciences, Statistical analysis, Internet, Documentation, Spacecraft


MRO DKF Post-Processing Tool

This software tool saves time and reduces risk by automating two labor-intensive and error- prone post-processing steps required for every DKF [DSN (Deep Space Network) Keyword File] that MRO (Mars Reconnaissance Orbiter) produces, and is being extended to post-process the corresponding TSOE (Text Sequence Of Events) as well. The need for this post- processing step stems from limitations in the seq-gen modeling resulting in incorrect DKF generation that is then cleaned up in post-processing.

Posted in: Briefs, Information Sciences, Computer software and hardware, Telemetry, Performance upgrades, Reliability, Spacecraft


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