Skip to content
View Simhaatt's full-sized avatar

Highlights

  • Pro

Block or report Simhaatt

Block user

Prevent this user from interacting with your repositories and sending you notifications. Learn more about blocking users.

You must be logged in to block users.

Content in all repositories owned by your account will be closed.
Maximum 250 characters. Please don’t include any personal information such as legal names or email addresses. Markdown is supported. This note will only be visible to you.
Report abuse

Contact GitHub support about this user’s behavior. Learn more about reporting abuse.

Report abuse
Simhaatt/README.md

Simhaa T. T.

Scientific ML researcher. I take a measurement problem from some corner of science — a leaf's reflectance spectrum, a cell's discharge curve, a microscope's point spread function — and work out what machine learning can honestly claim about it.

The domain changes every time. What doesn't is the discipline: hold something out, report the negative result, freeze the configuration, and ship code that regenerates every number in the paper from deposited artifacts.

  • Currently: Research student, Department of Electrical & Electronics Engineering, SSN College of Engineering, Chennai. Four manuscripts under review, each archived on Zenodo before submission.
  • Reach me: ORCID 0009-0006-9041-1103

Research

Six problems, five fields, one method: work out what the measurement can support, then refuse to claim more than that.

Field Problem, and what came out of it Artifact
Plant biochemistry
greenhyperspectra-compact-ssl
Predicting eight leaf traits from reflectance. 30 trait-specific bands beat all 1,721 (mean R² 0.624 vs 0.538) — and self-supervised pretraining, the fashionable answer, turned out to be complementary rather than superior. Reported with the failure: zero-shot transfer to a new acquisition source collapses, and 10–20% local labels only partly recover it. DOI
Optical physics
operator-mismatch-microscopy
When a microscope's real optics drift from the ones a reconstruction model assumed, can you still bound the error? Two instruments, four reconstruction methods. Severe aberration raises true error up to fivefold while the data-consistency residual goes down — the diagnostic everyone trusts points the wrong way — and 90% coverage falls to 0.31. The one-sided coverage inequality survives every evaluated cell. DOI
Remote sensing
Graph-RMS
Finding coherent regions in hyperspectral scenes with no labels and no idea how many classes there are. Sparse reciprocal graph → damped diffusion → robust mean-shift modes → reference-free consolidation, held out on Trento. Reports that Leiden on the same graph is competitive, rather than claiming a universal win. DOI
Battery reliability
battery-moo-recursive-forecasting
Forecasting capacity and resistance recursively, with architecture search given a matched budget against NSGA-II, NSGA-III and random search. 92.5% fewer parameters at statistically indistinguishable accuracy — stated as a parameter result, not an accuracy breakthrough. 12,600-trial log included. DOI
Reliability statistics
discret-hazard
Where discrete-time hazard models stop being valid for lithium-ion cells: link choice against interval width, effective sample size spanning two orders of magnitude, first-passage against hazard models. RESULTS.md is generated from results/, so the prose and the numbers cannot drift apart. DOI
Survival theory
grouped-ph-reproducibility
Separating the information lost by grouping survival times from the error introduced by reconstructing a Cox baseline afterwards: an exact finite-grid information-loss identity, a small-bin expansion, 34 frozen configurations across eight cohorts. With Sudheesh Kumar Kattumannil. DOI

Every package regenerates its reported tables and figures from deposited artifacts — CPU, minutes, no dataset download, no model retraining. Badges are concept DOIs, so they always resolve to the current version.

Systems

Project What it is
ocr 🏅 National finalist — MOSIP hackathon, IIT Madras Shaastra 2025. Document OCR, field mapping and fuzzy verification (PaddleOCR + FastAPI) wired into a MOSIP pre-registration flow: document-type-aware extraction, normalised fuzzy matching against the applicant's form, and per-field confidence a reviewer can correct.
money_muling_detection Money-mule detection over transaction graphs — PageRank, betweenness, cycle detection, Louvain communities and 72-hour smurfing windows behind a FastAPI + React app. Live demo.

Toolbox

Python · PyTorch · NumPy / SciPy · scikit-learn · NetworkX · conformal prediction · survival analysis · NSGA-II / NSGA-III · FastAPI · TypeScript / React · pytest · LaTeX

Pinned Loading

  1. ocr ocr Public

    Document OCR, field mapping and fuzzy verification (PaddleOCR + FastAPI) wired to a MOSIP pre-registration flow

    Python

  2. battery-moo-recursive-forecasting battery-moo-recursive-forecasting Public

    Recursive LSTM forecasting of battery degradation under matched-budget NSGA-II / NSGA-III search — 92.5% fewer parameters at indistinguishable accuracy (DOI 10.5281/zenodo.22067837)

    Jupyter Notebook

  3. Graph-RMS Graph-RMS Public

    Training-free, class-count-free spectral-spatial region discovery in hyperspectral images — reproducibility package (DOI 10.5281/zenodo.21876447)

    Python

  4. discret-hazard discret-hazard Public

    Validity boundaries of discrete-time hazard models for lithium-ion battery reliability — reproducibility package with a generated results report (DOI 10.5281/zenodo.22664399)

    Python

  5. greenhyperspectra-compact-ssl greenhyperspectra-compact-ssl Public

    Band- and label-efficient hyperspectral plant-trait prediction: 30 trait-specific bands beat all 1,721 (mean R² 0.624 vs 0.538) — reproducibility package (DOI 10.5281/zenodo.22755275)

    Python

  6. operator-mismatch-microscopy operator-mismatch-microscopy Public

    Conformal reconstruction-error bounds under forward-operator mismatch in computational microscopy — reproducibility package (DOI 10.5281/zenodo.22750126)

    Python