Skip to content

Junghwan Park, PhD

Health-data & AI policy · behavioral-science researcher · builder

Junghwan Park

I help build the data and AI backbone of a national health system — and write the research and the code behind it.

Junghwan Park directs the Division of Healthcare Data Development at Korea's Ministry of Health and Welfare, where he leads national strategy for health data and AI. He earned his PhD in public health at UC San Diego, where he built just-in-time adaptive interventions for physical activity using machine learning and control engineering. He also designs and ships AI and agent systems himself — from local-LLM research harnesses to deployed full-stack tools.

2020–2024
PhD, Public Health (Health Behavior) — UC San Diego / San Diego State University

Advisor: Eric Hekler. Dissertation: Optimizing Adaptive Interventions for Physical Activity.

2002–2011
BS, Bio and Brain Engineering (Bioinformatics) — Korea Advanced Institute of Science and Technology (KAIST)

Selected work

2017–2022 Policy

One Million Genomes Project

Planned the One Million Genomes Project, Korea's national bio big-data initiative to sequence and link genomic and clinical data at population scale. It launched in 2022 as a cornerstone of the country's precision-medicine strategy.

2020–2024 Research

JustWalk JITAI

Built the backend, mobile app, and monitoring system for JustWalk, an NIH-funded system-identification experiment, then applied machine learning and Bayesian regression to identify the "just-in-time" states where an intervention is most likely to help someone move.

2025 Eng

Lunit medical MoE on Apple MLX

Ported Lunit's open L1-16B-A3B medical mixture-of-experts model to Apple MLX and ran a disciplined 2–8-bit quantization sweep, scoring accuracy, speed, and memory on MedQA, MedMCQA, and PubMedQA in English and Korean — a concrete study at the intersection of medical AI and on-device inference.

2025 Policy

APEC High-Level Meeting on Health & the Economy

Led the planning team for APEC's 15th High-Level Meeting on Health and the Economy, hosted in Korea, and steered the negotiation of the Joint Ministerial Statement among member economies — advancing multilateral cooperation across the region.

2025–2026 Eng

Second-brain research engine

A self-completing research system that snowball-searches the literature, deduplicates with embedding similarity, runs a frozen local note-generation pipeline, stores everything in a knowledge graph, and periodically synthesizes findings — aimed at a queryable corpus approaching a hundred thousand papers.

2024 Research

Optimizing Just-in-Time Adaptive Interventions

Doctoral research optimizing just-in-time adaptive interventions by incorporating idiographic, dynamic predictions of behavior. It combined system identification, machine learning, and control engineering to decide when a digital coach should act to support physical activity.

2025 Eng

Light Thinker

A hierarchical multi-agent "thinking system" in which ephemeral agents reason continuously on small local models, passing context across generations in a pass-the-baton loop. An exploration of sustained, low-cost machine reasoning rather than one-shot prompting.

2024–2025 Policy

U.S.–Korea Pharma Trade & National Biosecurity

Led a cross-ministerial team developing Korea's response to U.S. pharmaceutical trade actions and a national biosecurity strategy, integrating twelve government ministries into a single framework for addressing biological threats and securing biopharmaceutical supply chains.

2025–2026 Eng

store — an LLM's second brain

A second brain, built from scratch. store is a Go service that gives a language model durable memory: a Postgres database extended with Apache AGE for graph edges and pgvector for embeddings, fronted by a BGE-M3 model so notes, entities, and conversations are written once and retrieved by meaning. It is the canonical-fact backbone that several of these other projects read from and write to — the quiet infrastructure that lets an agent remember across sessions.

Policy & strategy

2017–2020

National Medical Big Data Linkage Platform

Established the national platform linking KCDC, HIRA, and the Cancer Registry.

2017–2020

Health-Information De-identification Guideline

Drafted Korea's first health-information de-identification guideline.

2026–

AI Basic Health Strategy

Framework for universal access to AI-driven health, from R&D to industry.

2017–2018

'Right to Try' Act & Regenerative Medicine

Drafted a $1B R&D plan and led legislation for advanced regenerative therapies.

2012–2015

Social Security Information System

Ran a welfare fraud-prevention program that saved an estimated $2.5B.

2025

Are We Open?

Measured whether 734 Korean public-sector sites are reachable by AI crawlers.

Research

2024–

YourMove Control-Optimization Trial

An adaptive activity intervention optimized within a randomized controlled trial.

2023–2024

Agile Electrification (UCSD Design Lab)

ML modeling of home energy-load growth and homeowner energy literacy.

2005

HExDB: Human EXon Database

Human exon database for alternative-splicing analysis — early bioinformatics work.

2025

Reasoning with small models

Can a swarm of sub-1B local models reason like a frontier model?

2025

Neural Architect

An LLM designs and weight-tunes a network by reasoning — no backpropagation.

2025

LLM knowledge wiki

Passage-level personal knowledge wiki with an auto-generated ontology.

Engineering & building

2025

Dendrite RAG

Reference-crawling RAG that walks a seed paper's citation graph N levels deep.

2025

Chronos Nexus

Self-evolving multi-agent framework with pgvector long-term memory.

2025–2026

Shared agent–human mindmap

A deployed full-stack mindmap shared between agents and humans.

2025–2026

Autonomous data scientist

Autonomous data-science agent with a network-jailed, reproducible runner.

2025

Local paper-research assistant

Conversational paper-research assistant running on a local Gemma model.

2025

TikZ figure MCP server

An MCP server that generates publication-quality TikZ figures.

2025

Agents on bare metal

An LLM handed real microcontrollers, deciding what to build (with rbp-agent on RP2040).

Invited talks

March 2026

AI Capacity Building for the Health Workforce in Korea: From Medical AI to AI Medicine

Forum on Harnessing AI for Health Equity, Asian Development Bank (ADB), Manila

March 2026

Structural Characteristics of the Korean Health System and Digital Health Innovation

Stanford Graduate School of Business, invited lecture, Seoul

March 2026

AI Basic Health Framework

WHO Department of Digital Health and Innovation, online