Traffic congestion in tunnels, particularly phantom jams, significantly reduces driving efficiency and increases crash risks. To address this issue, a Pacemaker System (PMS) was implemented in the Geumnam Tunnel along the Seoul–Yangyang Expressway. A PMS aims to stabilize traffic flow and improve operational efficiency by guiding drivers to maintain uniform speeds through sequential LED illumination. This study aims to quantitatively evaluate the effectiveness of a PMS on traffic flow by analyzing Vehicle Detection System (VDS) data collected before and after its implementation. The analysis incorporated Level of Service (LOS) categories A–E, and distinguished between peak and non-peak hours to assess speed improvements and flow stabilization. The results indicated that the PMS increased the average speeds by approximately 6.5% across the LOS A–E conditions, with the most pronounced effects observed in LOS C–E. Furthermore, the speed distribution analysis revealed that the PMS enhanced lower-percentile speeds and reduced speed variance, thereby contributing to improved traffic stability. Statistical tests confirmed that the observed improvements were significant (p < 0.05). These findings demonstrate that the PMS effectively mitigates phantom jams and improves tunnel traffic efficiency, offering empirical evidence to support future PMS deployment and the development of tunnel traffic management policies.

ABSTRACT
1. 서론
    1.1. 연구의 배경 및 목적
    1.2. 연구의 방법 및 범위
2. 기존문헌고찰
    2.1. 터널 안전시설 관련 연구
    2.2. 국내외 PMS 적용 사례
    2.3. 시사점
3. 분석방법론
    3.1. 분석 대상 구간 선정
    3.2. VDS 데이터 수집 및 가공
    3.3. 서비스 수준별 데이터셋 구축
4. 분석 결과
    4.1. 서비스수준별 속도 증대 효과 분석
    4.2. 첨두·비첨두 속도 증대 효과 분석
5. 결론 및 향후 연구
감사의 글
REFERENCES

• 조영(한국건설기술연구원 수석연구원) | Jo Young
• 김용석(한국건설기술연구원 연구위원) | Kim Yongseok
• 정준화(한국건설기술연구원 선임연구위원) | Jeong Junhwa
• 신승철(서울시립대학교 스마트시티학과 박사과정, ㈜래도 연구소장) | Shin Seungcheol
• 이석기(한국건설기술연구원 연구위원) | Lee Sukki Corresponding author