About

On a windy spring day…

I'm Jin Sam Cho (ValleyJin) — an engineer and builder from Korea working where software meets business. My north star is simple: Coding + Business. Across two decades I've gone from national research labs to founding startups, and today I lead AI at K3I.

Launched

• 2026 — Present

  Kyopo AI

  Solo · designed & builtkyopo.ai

  Multilingual batch document translation into 50+ languages, designed and built end-to-end. Translates Excel, Word, HWPX, PowerPoint, PDF, and Google Workspace files in one pass while keeping tables and layout intact (files up to 5 GB). Sentence-level caching cuts cost up to 80%, with glossary control and text-to-speech in 40+ languages.

Experience

• 2026 — Present

  K3I Co., Ltd

  AX Leadk3i.co.kr

  Planning and building agentic AI applications, leading the company's AI transformation.

• 2022 — 2025

  Tokamak Network

  Product Manager & UI/UX Plannertokamak.network

  Product and UX for decentralized applications on Ethereum / OP-stack Layer-2 infrastructure.

• 2020 — Present

  OnTown Metaverse

  Founder & CEOOn.Town

  Built metaverse sites for startups and 10+ Technoparks.

• 2017 — Present

  TechValue

  Cofounder & CEOtechvalue.co.kr

  Built TechValue, online startup-valuation software.

• 2013 — 2015

  KAIST — Research Center for Future Strategy

  Senior Researcherkaist.ac.kr

  Built the Corporate Future Readiness Index (CFRI), a KAIST–JoongAng Ilbo joint project offering an alternative to conventional company valuation.

• 2003 — 2013

  KAERI — Korea Atomic Energy Research Institute

  Senior Researcherkaeri.re.kr

  Project manager of Korea's first 100 MeV proton accelerator; ran regional tech-transfer cooperation programs and evaluated the economic benefit of developed technology.

Skills

01 AI & Network Science

• Agentic AI applications on graph databases
• Deep Persona application development

02 Simulation

• ABM & Generative ABM (gABM)
• Parallel computing in Python
• 20+ yrs of technology-valuation Monte Carlo simulation

03 Web

• React.js · Node.js
• Java Spring framework

04 Blockchain

• dApp development in Solidity

05 Foundations

• Bankruptcy forecasting with AI (CNN & GANN)
• Advanced computer science

Education

• KAIST — Ph.D. Candidate, Graduate Program for Futures Strategy · Specialized in AI & Network Science2016 — Present
• KAIST — M.S., Graduate Program for Futures Strategy2013 — 2016
• Kyungpook National University — Ph.D. Candidate, Business Administration · Specialized in Financial AI2009 — 2012
• Kyungpook National University — M.A., Business Administration1998 — 2003
• Kyungpook National University — B.A., Business Administration1990 — 1998

Recognition

38Published articles

2Books authored

10+Korean patents

• 2005

  Minister's Commendation

  Ministry of Trade, Industry & Energy

  Awarded for contribution to Korea's 100 MeV proton accelerator development and to radioactive-waste facility site selection.

• 2003

  MBC Campus Music Festival — Grand Prize

  Composerlisten

  Awarded the grand prize as composer of the winning song.

Also: 10+ Korean patents (AI — bankruptcy forecasting with CNN & GANN; blockchain — contribution proof via smart contracts), bilingual in Korean and English, and a certified TCB analyst (Korea Technology Finance Corporation).

This site

A working journal. Posts are written in the open and the homepage stays in sync with my GitHub activity automatically.

Contact

Find me on GitHub, Medium, and X.

Chat with me on Telegram or KakaoTalk open chat.

Email: cho@kaist.ac.kr