About

A real-time multi-threading operating system that supports devices for the Internet of Things (IoT)
Using an Atmel’s Wi-Fi module (ATWINC1500), developed the first Wi-Fi driver for the Operating System, connecting it to the IPv6/6LoWPAN networking stack. This pull request is currently under reviews being done by the RIOT developer community

Winner of the Special Mention Award in 2018 IEEE Region 1 Micromouse Robotics Competition.
Mesigned a robot that solves a 16x16-sized maze. Created a multi-threaded robot application on an ARM Cortex-M processor with a real-time operating system (FreeRTOS).
Implemented artificial intelligence algorithms such as decision making and finite state machine. The algorithms are written with the C++ STL library.
Designed a PCB board using KiCad (an open-source alternative to Altium), with an ARM Cortex-M4F Microcontroller (STM32F446), 2 DC motor drivers, 4 custom-designed infrared range finders.

Winner of the Best Use of Amazon Web Service Prize at Hack@CEWIT Major League Hackathon.
Created a web application that allows users to control Arduino and Raspberry Pi wirelessly via an Amazon Web Service (AWS) cloud server, using protocols for the Internet of Things such as MQTT and Zigbee.
Designed architecture for the full-stack web application integrating SQLite database, extensive RESTful web API based on Python Flask web framework, and ReactJS client-side view.

Designed a speech recording server that manages 2000 concurrent sessions. The recording data is stored in AWS S3 storage in real-time.
Reduced data traffic down to 1/2 by migrating a backend audio encoding system to frontend and by converting a C/C++ written program into JavaScript and WebAssembly.

CR2 (Conference Room Reservation System) development team.
Was responsible for developing C# .NET MVC back-end web program, including designing new database tables and Microsoft Transact-SQL transactions that can handle 500 user requests from 200 active users while preventing request conflicts.

Developed Soldier Training Reporting System using PHP, MySQL, and JavaScript. The system provides web dashboards for training officers, replacing a Microsoft Excel-based management of the division, making it easier to keep track of around 400 soldiers’ training progress.
Served as a network administrator in the division. Maintained Cisco L3 routers and an Ericsson telephone exchange system of the division. Obtained Korea National Certificate of Intermediate Network Administrator during the service

Developed a robot localization system using MUltiple SIgnal Classification (MUSIC) algorithm to locate multiple robots and wireless sensor nodes based on multiple Wireless Signal Strength Indicator from wireless stations. The system detects location of robots with more than 90% of accuracy.
Implemented a wireless signal noise reduction algorithm using digital signal filters such as Kalman Filter. These filters contribute to improving accuracy from 60% to 90% by suppressing Gaussian noise and Rayleigh fading noise.
Designed a swarming algorithm for multiple robots using a divide and conquer strategy. A Matlab simulation tool is designed to test the algorithm easily.