AttachmentD-QuestionsandAnswers.pdf

Attachment D – Questions and Answers 80JSC026Q0001

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FAQ – DSDM RFP (80JSC026Q0001)

To all proposal teams:

Below are links to an additional source of data that you might consider proposing to use. The U.S. Navy DCS database has 649 saturation diving exposures that may augment altitude DCS modeling due to similarities between saturation diving conditions and ascents from sea level but proposal teams should consider the limitations. Non-saturation diving data can be considered but is may be less applicable to spaceflight exposures.

https://apps.dtic.mil/sti/pdfs/ADA451460.pdf https://apps.dtic.mil/sti/tr/pdf/ADA452742.pdf

The above has been incorporated into the PWS. The updated PWS has been posted with

80JSC026Q00010002.

Note:

This document contains responses to the questions that have been received to date. NASA makes these available to all proposal teams. Proposal teams should not contact NASA Subject Matter Experts directly as this represents an unfair advantage over other teams. NASA recommends that you check this document frequently throughout the proposal development process.

Some questions were asked by more than one proposal team or individual. For the sake of brevity, the question and response are not repeated for the same or similar inquiries. The exact wording of a question that you may have posed may not be in this document as a result.

All teams should prepare their proposals within the scope of the RFP.

Questions and Answers:

1. The solicitation states “The model must predict the risk of both Type I and Type II DCS”. Are you expecting something that provides high/medium/low risk or a numerical (ex. 10% +/- 5%) estimation of risk?

Numerical probabilities of Type I and Type II decompression sickness risk are preferred.

Confidence intervals or other appropriate statistical estimate of uncertainty are helpful.

2. Of the 1500 trials referenced, how many of these trials included positive Type I DCS? How many trials included positive Type II DCS?

Final compilation of all NASA DCS datasets is currently in progress. Of ~1400 compiled exposures so far, ~4% are cases of Type I DCS and ~1% are cases of Type II DCS.

3. Can you provide an example trial so we can see data formats?

No example datasets are provided. The proposals will be reviewed for their approach to the modeling. The dataset will be made available to the teams selected for funding as https://apps.dtic.mil/sti/pdfs/ADA451460.pdf https://apps.dtic.mil/sti/tr/pdf/ADA452742.pdf

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Records for each trial will contain at a minimum commonly recorded subject demographics, the starting ambient or cabin environmental conditions, parameters describing the nature of the prebreathe performed, the environmental conditions during the hypobaric phase of the test, the posture of the test subjects during testing, and whether signs and symptoms consistent with DCS were observed. Data will be distributed to the funded teams in a single Excel file (.xlsx).

Although data may not be available in all categories for each record, parameters for each subject exposure include: sex (M, F), age (years), height (cm), weight (kg), body fat (%), aerobic capacity (VO2 peak, mL/kg/min), peak heart rate during aerobic capacity test (beats per minute), ambient pressure before prebreathe (psia), breathing gas composition during prebreathe (% components), prebreathe duration (min), ambulation or sitting, metabolic load during prebreathe (% VO2 peak), decompression duration (min), ambient pressure during EVA simulation (psia), duration of EVA simulation (min), presence or absence of DCS Type I, presence or absence of DCS Type II, maximum VGE Spencer Grade (Grade 0 through IV), and time to maximum Spencer Grade (min).

4. Are undergraduate teams allowed to participate, if so, how many team members are allowed for a team? As we are all undergraduates, would it be recommended to have a faculty advisor for this project?

Yes this RFP is a Full and Open Competition. There is no team member limitations.

Please reference RFP, the Government does not have any recommendations.

5. Are there any citizenship requirements for team members interested in participating?

Please reference the RFP for Employment Eligibility Verification.

6. Would you be able to tell me if the data sets the subject of the Decompression Sickness solicitation (https://www.nasa.gov/hrp/risk-modeling-experts-help-nasa-develop-a-tool-for-predicting-decompression-sickness/) would be available to internal NASA analyst individuals or teams to evaluate? How do we obtain the dataset? What are the materials provided to us by NASA to develop our solution?

Please reference RFP.

7. Funding Structure: The total funding for the DSDM initiative appears to be substantial. How many contracts do you anticipate awarding? What is the expected average funding level per contract?

Please reference RFP.

8. Place of Performance: The solicitation states that “The work will be performed at locations specified by NASA.” Do you have guidance on how much time, if any, a performer will be expected to spend at JSC or another NASA facility? Are remote work arrangements acceptable for the majority of the effort?

All work can be performed remotely at the team’s home institution. There should be no expectation that awarded teams will visit NASA facilities through this award.

https://www.nasa.gov/hrp/risk-modeling-experts-help-nasa-develop-a-tool-for-predicting-decompression-sickness/ https://www.nasa.gov/hrp/risk-modeling-experts-help-nasa-develop-a-tool-for-predicting-decompression-sickness/

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9. NASA will provide a core dataset, and additional non-public datasets may be used.

For the core DSDM dataset:

Are marginal DCS events included in the outcome coding?

Almost all of the data records are labelled discretely as DCS or no DCS. There are rare cases (<0.5%) in which the data record was labeled as “ambiguous DCS”.

10. Does NASA have guidance on how marginal events should be coded for model fitting?

Best methods for managing marginal cases are at the discretion of the modeling teams.

11. Are the data provided in ANMRI format?

The data are not in ANMRI format.

12. Are there sufficient DCS events to support parameterization of these additional factors?

There are many environmental and individual factors that might be considered but there may be insufficient data to use all of them the development of an accurate model given the limited number of DCS cases and overall number of exposures. The NASA DCS database includes all available information to allow for various modeling approaches.

13. Does the data include repetitive exposures?

There is a subset of repeated exposures, but these are limited.

14. Is a technical report describing the core dataset available?

The following two links collectively give descriptions of NASA hypobaric exposures from the 1980s to mid 2010s. More recent exposures do not yet have a technical publication.

i. https://ntrs.nasa.gov/api/citations/20200004317/downloads/20200004317.pdf

ii. https://www.nasa.gov/wp-content/uploads/2023/03/conkin-dcs-case-description-research-tp218561-2014.pdf

15. Code Delivery Requirements:

• At the completion of Phase 1, full model documentation and source code delivery are required. My probabilistic DCS modeling system is written in C#.NET and can be delivered as a ready to open Microsoft Visual Studio solution. Is a complete Visual Studio solution an acceptable delivery format?

Yes, if detailed instructions for running the code are provided, along with the source code.

• Should the delivered code include only the optimized DCS model(s) and usage methods, or should the underlying optimization and analysis methods also be included?

A description of the optimization and analysis methods should be included.

• Should unit tests be included?

https://ntrs.nasa.gov/api/citations/20200004317/downloads/20200004317.pdf https://www.nasa.gov/wp-content/uploads/2023/03/conkin-dcs-case-description-research-tp218561-2014.pdf https://www.nasa.gov/wp-content/uploads/2023/03/conkin-dcs-case-description-research-tp218561-2014.pdf

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The Government has no recommendations, this will be at the discretion of the proposal team.

16. Exposure Planner and Acceptable Risk Levels. NASA will ultimately require a hypobaric exposure planner to optimize profiles, prebreathe protocols, exercise, and related factors. Should an exposure-planning capability be included in the “Suggestions on how to decrease the risk of decompression sickness to an acceptable level” deliverable?

A model that estimates the probability of DCS is required, and the model implementation should allow exposure planning functionality to compare various exposure plans.

17. Will NASA provide guidance on acceptable Type I/II DCS risk thresholds?

Current NASA standard 3001 (https://www.nasa.gov/reference/nasa-std-3001v2/) defines acceptable DCS Type I risk at ≤15% and Type II risk at 0%, but future exploration missions may require a different or modified risk posture. The model should not assume/require a single fixed risk threshold.

18. Phase 2 and Phase 3 Options: For performers who successfully complete Phase 1:

What are the anticipated durations of the Phase 2 and Phase 3 options? Will the scope of these options focus on model refinement, operationalization, or integration with NASA systems?

Phases 2 and 3 are expected to be one year each. Scope will include model refinement possible addition of additional diving, high altitude or other non-NASA chamber data as well as any new NASA chamber data.

19. Contracting Mechanism for Small Businesses: Which contracting company or contracting mechanism does NASA use for small business awards under this program? Are performers permitted to propose through a prime contractor if desired?

This acquisition is a Full and Open competition. Please reference the RFP.

20. Data Rights and Intellectual Property: Will NASA require Government Purpose Rights, Unlimited Rights, or Restricted Rights to the delivered source code? Will performers retain full rights to pre-existing tools, algorithms, and software libraries used in model development?

NASA will receive unlimited rights to the contract deliverables. Contractors retain rights in the proprietary model development tools. Please reference 80JSC026Q00010002 which includes the addition of applicable provisions/clauses.

21. Evaluation Metrics and Withheld Validation Data Will NASA evaluate model performance using a withheld validation dataset?

Please reference PWS.

22. Will evaluation metrics be specified in advance?

Please reference Evaluation Instructions.

https://www.nasa.gov/reference/nasa-std-3001v2/

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23. Will performers receive feedback on interim model performance?

Subject matter experts at NASA will be available to the awarded teams throughout the model development efforts. The performance of the models will be evaluated using standard statistical practices.

24. Security and Data Handling: - Will the dataset include PII or PHI requiring special handling? Are there restrictions on data storage? Are there cybersecurity requirements for development systems?

Data will be deidentified and have all PII and PHI removed. Other than good standard practices for controlling access to the data on a secured server (or similar) and maintaining quality records, there are no unique restrictions on data storage or security requirements. Sharing of data outside of the awarded research group is not allowed.

25. Computational Requirements: Are there constraints on runtime, hardware, or deployment environment for the delivered model? Must the model run offline, or is cloud-based computation acceptable? Are there restrictions on external dependencies or third-party libraries?

There are no specific constraints, but generally the model should have the capability to be run on an average office desktop computer with computation time on the order of minutes rather than hours. Models that can be run locally offline are preferable (no connection to an internet-enabled source or third-party library).

26. Deliverable Format Requirements: Does NASA require documentation in a specific format? Are there page limits or structure requirements for the final report?

Should the user guide follow a specific NASA template?

Formats .docx, .pptx, or .pdf are preferred. There are no page limits.

27. Microgravity exposure: We hypothesize that astronaut deconditioning may influence decompression outcomes. Do your records include information on individual durations of exposure to microgravity?

The NASA DCS database was derived from ground-based chamber exposures. When microgravity was simulated, test subjects refrained from and/or minimized ambulation during the hypobaric exposure. Subjects in the current NASA dataset were not deconditioned through bed rest or other spaceflight analog.

28. Applicable standard: You referenced the standard NASA-STD-7009. Would it be possible for you to provide the applicable version of this document?

The link to this document was provided in the solicitation and the URL is provided here:

https://standards.nasa.gov/sites/default/files/standards/NASA/B/1/NASA-STD-7009B- Final-3-5-2024.pdf

29. User interface requirements: Could you please indicate the type of interface you would expect (e.g. standalone application, analysis module, reporting tools)?

The user interface should allow a scientist, engineer, or physician with basic knowledge of decompression sickness and extravehicular activity (EVA) to input operational data (such as habitat pressure, breathing gas composition, prebreathe duration, EVA suit https://standards.nasa.gov/sites/default/files/standards/NASA/B/1/NASA-STD-7009B-Final-3-5-2024.pdf https://standards.nasa.gov/sites/default/files/standards/NASA/B/1/NASA-STD-7009B-Final-3-5-2024.pdf

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30. We would like to inquire about the possibility of participating directly in the hypobaric chamber tests conducted in Marseille. Such participation would allow us to evaluate the software under operational conditions and to contribute to the development of decompression profiles.

Please reference RFP.

31. Regarding project organization, we propose a two-phase approach: an initial pilot study based on approximately fifty cases, aimed at validating assumptions and ensuring alignment with your expectations. following your approval, a second phase involving the analysis of the full data set (approximately 1,500 cases). Please let us know whether this phased approach would be acceptable to you.

Please reference RFP.

32. Would you kindly confirm if this is an entirely new effort or is there an incumbent currently providing these services? If so, would you please provide the incumbent contract details?

Would you please provide us with an approximate timeline for the RFP release?This is an entire new acquisition, please reference RFP for timeline.

33. Can we collaborate with University Research Faculty members on this?

This RFP is a Full and Open Competition.

34. Are NASA civil servants eligible to participate in proposing a decompression sickness model?

This RFP is a Full and Open Competition.

35. I saw the email about decompression sickness proposals and was curious, even though I’m not an AI specialist, just as an interesting side project. I was wondering if there’s reference data on this which is publicly available, basically something someone could run a hypothetical system against to validate their ideas and concepts, as a way of proving that they’re on the right track. Thanks!

Please reference the RFP.

36. How does NASA define “commercial-off-the-shelf” and “System” for the purposes of the Evaluation Instructions requirement (Attachment B, Section 1.1, Item 1)? The PWS (Attachment A, Section 2.3) requires that offerors "...develop the proposed model within 8-month period based upon the training dataset that NASA makes available...", so that fundamental component cannot be commercial-off-the-shelf in the traditional sense.

Please see Attachment B, COTS language was removed.

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37. For the three past performance references, would subcontractor references count toward fulfillment?

Please see details in the RFP. Reference Attachment B Evaluation Instructions and Criteria

38. For this tool, what is NASA’s preferred use case?

An operational tool that allows input of spaceflight or spaceflight-like conditions (e.g., ground-based chambers) and outputs results via clear and accurate risk prediction of decompression sickness. This includes mission scenarios in which the crewmember might be exposed to multiple atmospheric profiles across the course of a mission.

39. I'd like to understand: is this opportunity open to international independent contractors, or is it restricted to US-based entities?

Please reference RFP for Buy American Act and Employment Eligibility Verification.

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