Tepna — working preprints https://tepna.net/papers/papers.html 2026-08-30T00:00:00Z Michal Planicka Respiratory rate from a Polar H10 chest accelerometer — Tepna preprint https://tepna.net/papers/acc-respiratory-rate.html 2026-08-30T00:00:00Z CGM variability ↔ nocturnal autonomic coupling — Tepna preprint https://tepna.net/papers/cgm-hrv-coupling.html 2026-08-30T00:00:00Z CPAP flow as a reference standard for wearable respiratory algorithms — Tepna preprint https://tepna.net/papers/cpap-flow-reference.html 2026-08-30T00:00:00Z A map of the walls: negative results in consumer physiological-signal analysis — Tepna preprint https://tepna.net/papers/dead-ends.html 2026-08-30T00:00:00Z Chest-accelerometer effort does not type apneas under CPAP — Tepna preprint https://tepna.net/papers/effort-typing-null.html 2026-08-30T00:00:00Z Age confounds apnea-driven HRV suppression — Tepna preprint https://tepna.net/papers/hrv-age-confound.html 2026-08-30T00:00:00Z We were measuring the wrong error — Tepna preprint https://tepna.net/papers/known-clock-recovery.html 2026-08-30T00:00:00Z How many nights? Minimum reliable recording length for ODI-4, rMSSD, and CGM-CV — Tepna preprint https://tepna.net/papers/nights-icc.html 2026-08-30T00:00:00Z Calibrating a null: a negative result is only as strong as the proof the instrument could have found a positive — Tepna preprint https://tepna.net/papers/null-calibration.html 2026-08-30T00:00:00Z Rolling-baseline ODI-4 under-estimates AHI in severe OSA — Tepna preprint https://tepna.net/papers/odi4-ahi-bias.html 2026-08-30T00:00:00Z Optical HRV against chest ECG on real overnight recordings — Tepna preprint https://tepna.net/papers/ppg-ecg-hrv-validation.html 2026-08-30T00:00:00Z Pooling epochs inverts signal-quality gate rankings — Tepna preprint https://tepna.net/papers/ppg-quality-gate-pooling.html 2026-08-30T00:00:00Z Beat-yield under apnea is modality-asymmetric — Tepna preprint https://tepna.net/papers/qrs-yield.html 2026-08-30T00:00:00Z Three-way rMSSD equivalence: PulseDex · ECGDex · PpgDex — Tepna preprint https://tepna.net/papers/rmssd-equivalence.html 2026-08-30T00:00:00Z A reproducible robustness benchmark: where consumer sleep detectors break — Tepna preprint https://tepna.net/papers/robustness-benchmark.html 2026-08-30T00:00:00Z Pinning a sensor's error without a reference: how many windows and how long — Tepna preprint https://tepna.net/papers/sensor-trio-nights.html 2026-08-30T00:00:00Z Per-device heart-rate uncertainty without a canonical reference — Tepna preprint https://tepna.net/papers/sigma-no-reference.html 2026-08-30T00:00:00Z What Tepna's harness reveals about the synthetic-physiological-data frontier — Tepna perspective https://tepna.net/papers/synthetic-data-frontier.html 2026-08-30T00:00:00Z Timestamp-pathology benchmark — analysis tool https://tepna.net/papers/timestamp-pathology-analysis.html 2026-08-30T00:00:00Z A deterministic benchmark of consumer-export timestamp pathologies and the floating wall-clock model — Tepna preprint https://tepna.net/papers/timestamp-pathology.html 2026-08-30T00:00:00Z Treatment-response detection: recovering the CPAP-start night — Tepna preprint https://tepna.net/papers/treatment-response.html 2026-08-30T00:00:00Z One phone is not one clock: two corrections to a negative result on beat-level fusion of two consumer wearables — Tepna preprint https://tepna.net/papers/wearable-clock-drift.html 2026-08-30T00:00:00Z