Cecilia Nyberg

Cecilia
Nyberg

AI Research & Engineering


Cecilia Nyberg

AI Engineer & Researcher

Hello! I'm Cecilia Nyberg, an AI researcher and engineer with experience in LLMs, agent systems and deep learning.

As a visiting researcher at the Deep Learning Lab at Seoul National University, I have worked across several areas of AI. My work on the quantized model BitNet b1.58 involved building a 1-bit LLM agent system, analyzing its limitations in long-context and multi-step tasks, and using continued pretraining and supervised fine-tuning to improve Korean language capability. I later shifted toward LLM tool-learning, studying why smaller models struggle with multi-step, domain-specific tool use. This led to a paper on prompt-robust tool learning for LLM-based ship inspection workflows using supervised fine-tuning and prompt augmentation. I am also working on modular CNN training strategies for image recognition, evaluated across six datasets and connected to early-exit network architectures.

On the applied side, I work as an AI Engineer and CPO at LLM Core AI, where I built a full-stack skincare assistant with a LangGraph-based agent architecture, memory, retrieval, streaming responses, Shopify integration, and deployment on Google Cloud Run.

I completed my Master's thesis at Ericsson in 2025, applying machine learning and time-series forecasting to optimize energy usage in radio units. A manuscript based on this work is currently under minor revision at IEEE Transactions on Machine Learning in Communications and Networking.

Research Areas

LLM Agents & Tool Use

Improving language models for multi-step tool use and structured decision-making workflows.

Efficient and Sustainable AI

Improving model performance with limited labeled data or constrained deployment settings, trough methods such as quantization, transfer learning and data-efficient training strategies.

Applied Deep Learning

Designing machine-learning systems for real-world applications, including operational decision support.

Multimodel AI

Interested in multimodal systems that combine medical image analysis and language models.

Experience

Oct 2025 — Present

AI Engineer

LLM Core AI, Inc. · Part-time · Seoul, South Korea

LLM-based agentic systems.

Jul 2025 — Present

Researcher

Seoul National University · Seoul, South Korea

Research on LLMs, tool-learning and quantization.

Jan 2025 — Jun 2025

Master Thesis Student

Ericsson · Stockholm, Sweden

Time series forecasting for energy-efficient dynamic voltage control in radio units.

Jun 2024 — Jul 2024

Software Developer

Ongoing · Full-time · Gothenburg, Sweden

Implementation of additional service selection functionality for transport bookings in WMS. C#, HTML and more.

Education

Aug 2023 — Jun 2025

Master's Degree, Data Science and AI

Chalmers University of Technology

Image recognition, LLMs, medical AI.

Sep 2024 — Dec 2024

Graduate Student, Data Science and AI

Seoul National University

Graduate courses focused on LLMs, meta-learning and ML techniques.

Jun 2023 — Aug 2023

Coursework in Economics

University of California, Berkeley

Aug 2020 — Jun 2023

Bachelor's Degree, Industrial Engineering and Management

Chalmers University of Technology

Operations management, financial analysis, computer science track.

Publications

2026

Learning to Optimize Voltage Level for Energy-Efficient Radios. C. Nyberg et al.

IEEE Transactions on Machine Learning in Communications and Networking

Manuscript under minor revision.