REG NASA-LLIS-1596-2005 Lessons Learned Spatial Scene Requirements and Sampling Rates.pdf

1、Lessons Learned Entry: 1596Lesson Info:a71 Lesson Number: 1596a71 Lesson Date: 2005-02-10a71 Submitting Organization: LARCa71 Submitted by: Kimberly Graupnera71 Authored by: John StoughtonSubject: Spatial Scene Requirements and Sampling Rates Abstract: The requirements for the ensemble suite were de

2、rived from the scene requirements which were derived from the individual technologies, which made it difficult to establish measurement criteria for the ensemble suite. Unique to the GIFTS Project was the program requirement to design the instrument using specified technologies. Description of Drivi

3、ng Event: GIFTS suffered from a lack of “ensemble suite” requirements (joint ensemble performance metrics). GIFTS started out with no project-defined, Level 1 scene requirements. Instead, scene requirements were derived from the individual technologies. For these reasons, it became difficult to esta

4、blish measurement criteria for the ensemble suite. This hampered the allocation of requirements to lower levels. This led to too many “implied” requirements left open to interpretation by the implementers. GIFTS could have benefited more by assessing how the individual technology scene requirements

5、either helped or hindered the ensemble suite requirements. More work was needed to refine the scene requirements so that requirements could be allocated and flowed down. More work was needed to define verifications that could be measured and tested. Lesson(s) Learned: Establish the scene requirement

6、s for the ensemble suite, and then allocate the requirements to the sensors. Establishing the Level 1 requirements enables the design team to assess the end performance characteristics of the ensemble suite and determine the design parameters for the sensors. Establish the Level 1 spatial density an

7、d quality requirements for the ensemble suite at the start of Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-the program. Scene dynamic ranges should be translated into measurable, testable requirements. (Anecdote: “Cant measure a cloud, but can mea

8、sure its temperature.”) Recommendation(s): Establish requirements at the start and do no vary. Start with a vision, and add the technologies on how to accomplish the vision. Evidence of Recurrence Control Effectiveness: N/ADocuments Related to Lesson: N/AMission Directorate(s): a71 ScienceAdditional Key Phrase(s): a71 Risk Management/AssessmentAdditional Info: Approval Info: a71 Approval Date: 2006-06-30a71 Approval Name: tmasona71 Approval Organization: HQProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-