arXiv subjects

Jinhao Yang

Publications and source records attributed to Jinhao Yang.

3 recordsLinked to original sources

arXiv2026

Point-in-Time Audit Before Alpha: Public-Archive Availability and a Negative Matched-Budget Study on BTC Perpetual Futures

Public cryptocurrency archives may appear usable when files exist, although factor research requires observations available and executable at each decision time. We audit public Binance BTCUSDT USD-M perpetual-futures data using event, publication, and availability times and separate proposal from deterministic auditing, evaluation, and holdout access. An initial gapless five-minute requirement for trade, mark, index, and open interest failed: the longest unrepaired intersection was 304.5729166666667 days. A disclosed revision made trade, mark, index, and realized funding the core streams and made open interest optional because its publication time was unverified. The revised mask retained 727 complete UTC days and supported a 436/145/146-day train, validation, and historical-holdout split. On 80 frozen known-rule templates, the auditor detected 40/40 violations and rejected 0/40 legal templates. Across ten null-signal paths, full auditing reduced mean false passes from 0.2910 to 0.0625. Under matched valid-candidate budgets, the audited adaptive agent tied random search and did not establish superiority. In the one-time historical holdout, all evaluated runs had positive IC but negative net Sharpe under primary costs. We therefore report a scoped negative result rather than a profitability or agent-superiority claim.

cs.SE↗

arXiv2026

Spike-Killer: Evidence-Gated LLM Assistance for Safe Performance Diagnosis on a Real Windows Workstation

LLM-assisted agents can synthesize system evidence, propose configuration changes, and automate diagnostic tasks, but their flexibility makes an imprecise action or an intrusive collector an operational risk. We present Spike-Killer, a human-approved workflow for diagnosing frame-time complaints on one real Windows workstation. The workflow treats each action as an evidence-gated transaction: it records the exact target state, classifies risk, preserves a snapshot, verifies a postcondition, and retains failed measurements as first-class evidence. This experience paper reports a completed same-day study with Counter-Strike 2 as a demanding target application. The evidence bundle contains preserved state snapshots, exploratory microbenchmarks, a ten-run same-state repeatability probe, live telemetry, a repaired over-broad registry action, incompatible presentation-capture attempts, an invalid local replay, and a system-level tracing replacement. Windows Performance Recorder produced two CS2 local-Bot GPU traces of 90.69 and 85.85 seconds; both were attributed to cs2.exe, exposed DxgKrnl Present metadata, and had zero lost ETW buffers or events. These results qualify trace integrity, not performance: the study reports no frame intervals, P99 estimate, or intervention effect. The contribution is an auditable, human-in-the-loop pattern for trustworthy agent assistance on a real workstation, including explicit stop conditions when evidence is insufficient.

cs.SE↗

arXiv2025

A region-specific brain dysfunction underlies cognitive impairment in long COVID brain fog

Long COVID "brain fog" is a common and debilitating subjective syndrome often associated with persistent cognitive impairment after COVID-19 infection. Here we identify a specific regional brain dysfunction that mediates this cognitive impairment and provide evidence that targeted neuromodulation improves this deficit. In 120 patients with long COVID brain fog, we found an aberrant perceptual processing pattern. Patients with more severe brain fog committed significantly more false alarms (impulsive responses to non-signals) despite preserved overall accuracy. Both high-density (128-channel) EEG and structural MRI analyses provided converging evidence of a right inferior insula deficit, characterized by a blunted neural monitoring signal and cortical atrophy. We confirmed this deficit in a separate 796-participant UK Biobank longitudinal COVID re-imaging cohort, where COVID-19 survivors also showed selective impairment on a perceptual processing task and corresponding longitudinal atrophy of the right inferior insula compared with healthy controls. Finally, in a proof-of-principle randomized, sham-controlled trial (n = 40), a non-invasive, excitatory theta-burst ultrasound stimulation protocol targeting the right inferior insula rescued the perceptual deficit by reducing false alarms. These findings provide evidence of a causal role for right inferior insula dysfunction in long COVID-related perceptual impairment and show that modulation of this region can rescue the deficit, establishing it as a novel therapeutic target for long COVID cognitive impairment.

q-bio.NC↗