StandardInternational professional-learning synthesis · ABET 2026–27 · IEA GAPC v4 · ASCE ethics and AI responsibility · NIST AI RMF 1.0
Source3 source files
Review stateTechnical and publication gates pending
After this chapter, you should be able to
- Distinguish classification, detection and segmentation.
- Audit image scale, labels and acquisition conditions.
- Calculate detection metrics.
- Assess domain shift and near-duplicate leakage.
- Specify quality gates, abstention and inspector handoff.
Engineering context and methodSource §Lesson 09 · Engineering context and method · CASE-01 · RES-07 · RES-08 · DATA-07
An image records surface appearance under a particular scale, focus, lighting, angle and occlusion. A pixel, box or class does not establish depth, cause or structural consequence. Split by asset, site or acquisition campaign so near-duplicate crops cannot cross partitions. FHWA-HRT-24-055 describes research and validation activity; it is not evidence that AI replaces mandated inspection.
Verified worked exampleSource §Lesson 09 · Verified worked example · CASE-01 · RES-07 · RES-08 · DATA-07
Image-screening confusion matrix
For 200 images, TP = 32, FP = 8, FN = 8 and TN = 152.
- Precision
32 / (32 + 8)
0.80 - Recall
32 / (32 + 8)
0.80 - Specificity
152 / (152 + 8)
0.95 - F1
2×0.8×0.8/(0.8+0.8)
0.80
Result. Eight labelled positives were missed. The system may rank images for review only, with capture-quality and out-of-domain abstention.
Practical lab · 5 h lesson effortSource §Lesson 09 · Practical lab · 5 h lesson effort · CASE-01 · RES-07 · RES-08 · DATA-07
- Use the rights-cleared precomputed result table until image rights approval is recorded.
- Compare thresholds and analyse at least five false positives and five false negatives.
- Define blur, scale, lighting, occlusion and domain-shift quality gates.
- Write an inspector handoff stating what the image output cannot determine.
Failure modes to investigateSource §Lesson 09 · Failure modes to investigate · CASE-01 · RES-07 · RES-08 · DATA-07
- Near-duplicate crop leakage.
- No physical scale or acquisition metadata.
- Internet-image domain mismatch.
- One annotator treated as unquestionable truth.
- Segmentation described as calibrated crack width without evidence.
Knowledge checksSource §Lesson 09 · Knowledge checks · CASE-01 · RES-07 · RES-08 · DATA-07
| Question | Answer rationale |
|---|---|
| Does a crack pixel imply structural distress? | No; geometry, cause, depth and asset context require engineering assessment. |
| Why split by asset or campaign? | Crops and conditions from one acquisition are correlated. |
| What triggers abstention? | Inadequate quality, scale, view or out-of-domain content. |
| What is label uncertainty? | Qualified reviewers may disagree or lack sufficient evidence. |
| What does the FHWA case establish? | A research system is being developed and validated, not approved as replacement inspection. |
Key points
- Start from the accountable engineering decision and its consequence.
- Compare against a transparent non-AI baseline.
- Validate on a split that represents intended use and retain human authority.
Source references recorded by the supplied chapter
- FHWA-HRT-24-055, Artificial Intelligence for Bridge Inspection research report.
- Peer-reviewed civil-infrastructure vision reviews listed as RES-07 and RES-08.
- ASCE Policy Statement 573.