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SCIENCE · INVESTIGATE AND EXPLAIN

Revise reasoning without erasing the first attempt

Apply seven review criteria to a bounded design argument and plan unfamiliar transfer evidence.

Learning outcome: Use evidence-linked feedback, preserve the original report and distinguish supported practice from independently reviewed performance.

Starting recap

A complete text field is evidence of a record, not a judgment of its scientific quality.

All lessons are open directly. Your saved experiments remain when you leave and return.

Try

A reviewer notices that a report used only the final temperature while the first two tail samples failed.

Open the experiment

Predict

Predict whether changing a conclusion alone can repair the omitted evidence and method.

Experiment

Use a saved suite capture to draft an original argument, then review it against the seven criteria. Write a separate revision that corrects a substantive issue and names what evidence changed; keep both versions.

Compare failures and constrained design tradeoffs

Worked teaching model · synthetic values · Twelve fixed candidates and four public deterministic cases reuse engineering-device-v1. Keep hardware, gain and correction fixed across each four-case suite. Case pass counts are coverage of supplied conditions, not field reliability, probabilities, independent trials or physical validation. Feasibility requires every supplied criterion; energy and assigned token cost are separate conditional objectives. An empty robust feasible set is a supported result, not permission to relax requirements silently.

Reset keeps your prediction, captures and practice history.

Keep the candidate fixed while changing the test condition

1: gain 2 W/K · Standard enclosure · subtract 0°C. Each matrix row retains one gain, hardware and subtracted correction across all four public scenarios. The selected detail scenario is Nominal. Changing the scenario selector inspects a different condition; it does not retune this candidate.

These are 48 deterministic model combinations, not 48 manufactured devices or independent trials. Passing a fraction of these four selected cases describes only this public suite; it is not a field reliability probability. All outcomes are development evidence with known public exposure.

Compare all twelve candidates across four scenarios
Every supplied criterion is retained. A cell passes only when all four pass.
Fixed candidateNominalTwo-sample delay (20 s)Sensor offset +2 degCHeater limited to 8 WCases meeting all criteria
1: gain 2 W/K · Standard enclosure · subtract 0°C (selected)
Tail 29–31°C at 90–120 s: pass
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: pass
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
2 / 4
Not feasible across all four
2: gain 2 W/K · Standard enclosure · subtract 2°C
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: pass
Input ≤2000 J: fail
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: pass
Input ≤2000 J: fail
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: pass
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
1 / 4
Not feasible across all four
3: gain 2 W/K · Insulated enclosure · subtract 0°C
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: fail
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: pass
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
1 / 4
Not feasible across all four
4: gain 2 W/K · Insulated enclosure · subtract 2°C
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: fail
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: fail
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
0 / 4
Not feasible across all four
5: gain 6 W/K · Standard enclosure · subtract 0°C
Tail 29–31°C at 90–120 s: pass
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
1 / 4
Not feasible across all four
6: gain 6 W/K · Standard enclosure · subtract 2°C
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: pass
Input ≤2000 J: fail
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: fail
Input ≤2000 J: fail
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: pass
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
1 / 4
Not feasible across all four
7: gain 6 W/K · Insulated enclosure · subtract 0°C
Tail 29–31°C at 90–120 s: pass
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: fail
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
1 / 4
Not feasible across all four
8: gain 6 W/K · Insulated enclosure · subtract 2°C
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: fail
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: fail
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: pass
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
1 / 4
Not feasible across all four
9: gain 12 W/K · Standard enclosure · subtract 0°C
Tail 29–31°C at 90–120 s: pass
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
1 / 4
Not feasible across all four
10: gain 12 W/K · Standard enclosure · subtract 2°C
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: pass
Input ≤2000 J: fail
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: fail
Input ≤2000 J: fail
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: pass
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
1 / 4
Not feasible across all four
11: gain 12 W/K · Insulated enclosure · subtract 0°C
Tail 29–31°C at 90–120 s: pass
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: fail
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
1 / 4
Not feasible across all four
12: gain 12 W/K · Insulated enclosure · subtract 2°C
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: fail
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: fail
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: pass
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
Tail 29–31°C at 90–120 s: fail
Peak ≤32°C: pass
Input ≤2000 J: pass
Cost ≤6 tokens: pass
1 / 4
Not feasible across all four

No candidate meets all four scenarios in this finite suite. In particular, the 8 W case fails the finite-time tail requirement even for insulated hardware. Its constant-input equilibrium is 20 + 8/0.5 = 36°C, but its 200 s time constant means the 20°C start reaches only about 27.219°C after 120 s. This is a finite-time service failure, not proof that insulation makes 29°C permanently unreachable. Standard hardware instead has an 8 W equilibrium of 28°C.

Selected candidate: separate requirements in each condition

Same candidate, same initial temperature and 120 s horizon; scenario changes are explicit
ScenarioTail samples at 90, 100, 110, 120 s (°C)Peak (°C)Applied input (J)Assigned costAll criteria
Nominal29.359, 29.542, 29.673, 29.766
Pass
29.766 at 120 s
Pass
1821.035
Pass
3 tokens
Pass
Pass
Two-sample delay (20 s)30.341, 30.359, 30.294, 30.201
Pass
30.359 at 100 s
Pass
1922.517
Pass
3 tokens
Pass
Pass
Sensor offset +2 degC28.187, 28.324, 28.422, 28.492
Fail
28.492 at 120 s
Pass
1607.588
Pass
3 tokens
Pass
Fail
Heater limited to 8 W24.747, 25.057, 25.337, 25.590
Fail
25.590 at 120 s
Pass
960.000
Pass
3 tokens
Pass
Fail

Temperature judgments use full precision, not rounded display values. Held-input exact one-node intervals are monotonic toward their interval equilibria, so endpoint samples bound their peaks and the intervening tail temperatures here. This is not a general claim about physical temperature fields. A passing energy budget cannot compensate for a failed temperature requirement.

Cost and input energy within one feasible scenario

For Nominal, feasible means meeting all four supplied requirements. The comparison then minimizes only assigned token cost and applied heater energy. A candidate is nondominated if no other feasible candidate is no worse on both and strictly better on at least one. Equal pairs do not dominate each other. This conditional comparison excludes other priorities and is not a universal best design.

Feasible candidates only · fixed axes: cost 3–5 tokens, input 0–2400 J
0600120018002400345Applied heater input (J)Assigned resource cost (tokens)

Circles: feasible pairs. Outer squares: nondominated pairs. Identical or nearby points can overlap; the table retains every candidate. Points outside the fixed scale are omitted with a notice, never moved onto the boundary.

Nominal: retain rejected candidates and their failed criteria alongside the feasible comparison
CandidateCost (tokens)Applied input (J)Failed criteriaCost–energy status
1: gain 2 W/K · Standard enclosure · subtract 0°C31821.035488NoneFeasible and nondominated
2: gain 2 W/K · Standard enclosure · subtract 2°C32012.930200Tail 29–31°C at 90–120 s; Input ≤2000 JExcluded: infeasible
3: gain 2 W/K · Insulated enclosure · subtract 0°C51624.624719Tail 29–31°C at 90–120 sExcluded: infeasible
4: gain 2 W/K · Insulated enclosure · subtract 2°C51809.091605Tail 29–31°C at 90–120 s; Peak ≤32°CExcluded: infeasible
5: gain 6 W/K · Standard enclosure · subtract 0°C31887.808894NoneFeasible, dominated on cost/energy
6: gain 6 W/K · Standard enclosure · subtract 2°C32130.915020Tail 29–31°C at 90–120 s; Input ≤2000 JExcluded: infeasible
7: gain 6 W/K · Insulated enclosure · subtract 0°C51558.581071NoneFeasible, dominated on cost/energy
8: gain 6 W/K · Insulated enclosure · subtract 2°C51790.699641Tail 29–31°C at 90–120 s; Peak ≤32°CExcluded: infeasible
9: gain 12 W/K · Standard enclosure · subtract 0°C31893.370525NoneFeasible, dominated on cost/energy
10: gain 12 W/K · Standard enclosure · subtract 2°C32153.177644Tail 29–31°C at 90–120 s; Input ≤2000 JExcluded: infeasible
11: gain 12 W/K · Insulated enclosure · subtract 0°C51515.220813NoneFeasible and nondominated
12: gain 12 W/K · Insulated enclosure · subtract 2°C51757.975786Tail 29–31°C at 90–120 s; Peak ≤32°CExcluded: infeasible
Selected run: all thirteen true states
1: gain 2 W/K · Standard enclosure · subtract 0°C · Nominal
Time (s)True temperature (°C)
020.000000
1021.903252
2023.625385
3025.183636
4026.558649
5027.541112
6028.243095
7028.744670
8029.103051
9029.359119
10029.542083
11029.672812
12029.766220
Selected run: all twelve observation, command and energy receipts

Commands occur at 0–110 s; 120 s is the final state, not a new observation command. The delayed scenario requests t − 20 s. Negative requested times use the held initial state at effective time 0, not a measured prehistory. Raw indication adds the scenario bias to the selected true observation; corrected indication subtracts the candidate correction of 0°C. A nonzero correction is not automatically appropriate in an unbiased scenario.

Held input for each 10 s interval; positive ambient energy is outward
Step / interval (s)True start → end (°C)Requested / effective observation (s)Raw / subtracted correction / corrected (°C)Error (K)Requested / applied (W)ClippingInput (J)Stored change (J)To ambient (J)Residual (J)
0: 0–1020.000000 → 21.9032520 / 020.000000 / 0 / 20.00000010.00000030.000000 / 20.000000Upper200.000000190.3251649.6748360.00e+0
1: 10–2021.903252 → 23.62538510 / 1021.903252 / 0 / 21.9032528.09674826.193497 / 20.000000Upper200.000000172.21333027.7866700.00e+0
2: 20–3023.625385 → 25.18363620 / 2023.625385 / 0 / 23.6253856.37461522.749230 / 20.000000Upper200.000000155.82506544.1749350.00e+0
3: 30–4025.183636 → 26.55864930 / 3025.183636 / 0 / 25.1836364.81636419.632729 / 19.632729None196.327288137.50130258.8259860.00e+0
4: 40–5026.558649 → 27.54111240 / 4026.558649 / 0 / 26.5586493.44135116.882703 / 16.882703None168.82702898.24636570.5806630.00e+0
5: 50–6027.541112 → 28.24309550 / 5027.541112 / 0 / 27.5411122.45888814.917775 / 14.917775None149.17775570.19823278.9795230.00e+0
6: 60–7028.243095 → 28.74467060 / 6028.243095 / 0 / 28.2430951.75690513.513811 / 13.513811None135.13810850.15749784.9806120.00e+0
7: 70–8028.744670 → 29.10305170 / 7028.744670 / 0 / 28.7446701.25533012.510661 / 12.510661None125.10660935.83814689.2684630.00e+0
8: 80–9029.103051 → 29.35911980 / 8029.103051 / 0 / 29.1030510.89694911.793898 / 11.793898None117.93898025.60679592.3321850.00e+0
9: 90–10029.359119 → 29.54208390 / 9029.359119 / 0 / 29.3591190.64088111.281762 / 11.281762None112.81762118.29636994.5212520.00e+0
10: 100–11029.542083 → 29.672812100 / 10029.542083 / 0 / 29.5420830.45791710.915835 / 10.915835None109.15834713.07298096.0853680.00e+0
11: 110–12029.672812 → 29.766220110 / 11029.672812 / 0 / 29.6728120.32718810.654375 / 10.654375None106.5437519.34080497.2029470.00e+0

Whole-run balance: 1821.035488 J applied input = 976.622047 J stored change + 844.413440 J signed ambient transfer. Residual -3.41e-13 J. Display rounding can create a small apparent discrepancy.

Original fictional one-node device and assigned costs. Uniform temperature, constant heat capacity/conductance/ambient, held heater input and exact exponential propagation within each sample. No spatial gradient, evaporation, radiation law, random noise, active cooling, integral control or physical safety/efficiency/reliability certification. Public cases are exposed teaching practice. The 2000 J requirement is an acceptance criterion, not an automatic cutoff. Token cost is fictional; heater input is not a measured wall-plug consumption. No averaging of these indicators repairs a failed requirement.

Your investigation: predict the scenarios a fixed candidate will fail, inspect its receipts and retain a failure explanation. Compare a second candidate without changing the criteria. Explain one tradeoff and one condition outside this finite public suite before recommending a design.

Selected fixed candidate meets all criteria in 2 of 4 supplied public cases. Nominal: all requirements met.

Selected case: 1821.035 J applied heater energy; 3 assigned tokens. 5 feasible candidates in this scenario; 2 nondominated on cost and energy. This case count is not field reliability. Changing correction between scenarios would define different candidates.

Captures preserve recipes and replay their calculated results. They are synthetic model evidence, not physical measurements.

Understand

Review the reasoning, not the polish

A clear report can still omit a required measurement or use an invalid model. Choose a saved suite capture and write an initial argument in your notes. Preserve that version before applying the review below. The current lesson is a guided review exercise using development evidence; it does not itself create an immutable cumulative-project submission or authenticate a reviewer.

Use a concrete defect: a report declares delayed standard gain 6 successful because the final temperature is about 29.695°C. Its omitted 90- and 100-second values are about 31.474°C and 31.295°C, both above the required 31°C ceiling. The problem is not style. The method checked an endpoint instead of every specified tail sample, so the conclusion must change.

Apply seven criteria to the same artifact

Use these exact criteria and connect each judgment to a passage, table or missing item:

  • Question and prediction: Is the question answerable, and was the prediction made before the relevant result? Disclose familiarity with public cases.
  • Model and assumptions: Are the boundary, units, candidate, scenario, update order and omitted processes explicit?
  • Method: Are the baseline, alternatives, matched conditions and full requirement window reproducible?
  • Evidence integrity: Are original modeled receipts retained and distinguished from observations, calculations and supplied answers?
  • Analysis: Are arithmetic, representations and comparisons correct, with no failed criterion hidden by another success?
  • Explanation and transfer: Does the claim follow from evidence, address an alternative and respond appropriately to a changed condition?
  • Revision: Does the new version respond substantively to feedback or contradictory evidence while preserving the first?

A short supporting comment should identify what the reviewer actually inspected. “Looks good” is insufficient. For the defective report, a useful analysis comment names the two omitted values and their times. A method comment asks for the same four tail samples for every compared candidate. These comments produce a specific next action.

Use evidence labels honestly

The course review labels are not yet evidenced, supported with guidance, and demonstrated independently on the assigned case. Each needs a supporting comment. The first two also need a targeted retry: a particular calculation, comparison or evidence gap to repair. Completing text fields is not a grade, and numerical agreement alone cannot establish method quality or causal reasoning.

A public worked example can support guided learning but cannot establish an unfamiliar independent task. That requires a human-supplied assignment with adequate evidence and assumptions, an exact record of the response being reviewed, and disclosures of prior exposure and assistance. Locally recorded reviewer identity and date are assertions, not authenticated credentials. Physical technique requires review of work actually performed, not inferred competence from a browser model.

Revise the argument and its evidence together

Keep the original failed claim. In a separate version, include all four tail samples, change the conclusion to a tail-band failure and explain why final-only checking was inadequate. Then compare a proposed revision, such as delayed standard gain 2 with zero correction, using the same complete window. Preserve the original candidate’s other passing criteria and the revised candidate’s energy tradeoff.

NASA’s verification guidance connects evidence with declared requirements. The purpose of review here is similarly concrete: determine whether the supplied evidence supports the stated claim. Correcting a title or adding confident language does not repair omitted data. Nor should a reviewer demand a predetermined preferred candidate when several choices meet different legitimate priorities.

Transfer: respond to a changed sensor relationship

A human could supply an unfamiliar sensor packet, but this paper example is public: reference temperatures 20, 30 and 40°C indicate 22, 33 and 44°C. A draft subtracts two degrees everywhere and claims successful calibration. Write one evidence-linked review comment and one targeted retry before opening the answer.

Check the calibration-review transfer

A useful comment is: “The indication-reference differences are 2, 3 and 4°C; at the 40°C reference, subtracting 2 leaves 42°C, so a constant two-degree correction does not fit all supplied points.” A targeted retry is to compare additive-offset and scale-error explanations using every reference, retain originals and propose an additional reference check. A new fitted relation still requires uncertainty and scope limits before use with actual hardware.

NIST’s traceability discussion supports documenting reference relationships rather than treating a correction as universal proof of fitness. Finish with both report versions, the reviewer comments and your response to each. Return to reproducible results or unfamiliar failures for targeted practice. A substantive revision records what changed and why; it does not erase the path that revealed the error.

Apply

A reviewer finds that two required tail samples were omitted. Which revision is substantive?

Public practice checks a specific claim. It does not establish independent mastery.

Explain how assignment identity, prior exposure and assistance constrain any independent-review claim, and why public worked answers do not supply that evidence.

Continue

Completion requires a saved prediction, at least one capture and a reflection. Presence checks do not grade your reasoning.

Skipping retains experiments and awards no mastery.

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