A Quantitative A naly sis of the Fire Hazard Generated from Hydrogen Fuel Cell Electric Vehicles

Sungwook Kang(Sungwook Kang),Kyu Min Lee(Kyu Min Lee),Minjae Kwon(Minjae Kwon),Ohk Kun Lim(Ohk Kun Lim),Joung Yoon Choi(Joung Yoon Choi) 한국화재소방학회 2022 International Journal of Fire Science and Engineer Vol.36 No.2

There is a lack of information on (i) the potential fire load of new green-technology vehicles, (ii) flame spread behavior, (iii) thermal impacts on high-pressure hydrogen storage vessels (HSVs) and lithium-ion batteries (LIBs) during fuel cell electric vehicles fires (FCEVs), and (iv) thermal damage to adjacent vehicles and upper structural members during FCEV fires occurring in civil structures, such as underground spaces, multi-story parks, and tunnels. In view of this, a full-scale fire test was conducted in this study to quantitatively assess the fire risk of hydrogen FCEVs. Large-scale cone calorimetry was used to quantify the thermal intensity released from the FCEV fire. The flame spreading behavior through an FCEV with HSVs and LIBs was observed using the thermocouples installed. Changes in the temperature and irradiance around the FCEV fire were also measured using an instrumented test rig. The peak heat release rate, total heat released, and fire growth rate were observed to be 5.99 MW, 11.8 GJ, and 0.0055 kW/s², respectively. The temporal point of hydrogen gas release from the HSVs' thermal pressure relief device (TPRD) was estimated to be 16.2-26.2 min. The initiation of thermal runaway of LIBs was deduced from the temperature-time profiles of the LIB modules and their metal housing approximately 22.2 min after HCEV ignition. Moreover, FCEV fires could thermally impair adjacent upper structural members by 800 ℃ combustion gas for at least 13 min and emit a median heat flux of 27.2 kW/m² (peak heat flux of 76.5 kW/m²) to adjacent vehicles. The measurements and findings obtained from this study can contribute to the evaluation of and further studies on newly emerging fire hazards.

The Effect of the Introduction of the Express Highspeed Railway in Korea

SungWook KANG(SungWook KANG),SukMun OH(SukMun OH),GyuBae KIM(GyuBae KIM) 동아시아경상학회 2022 The East Asian Journal of Business Economics Vol.10 No.4

Purpose – In today's era of carbon neutrality, railways need to find ways to improve usability and efficiency. Accordingly, this study examines the effect of introducing express highspeed railways into the Korean public transportation system and suggests some practical guidelines. One concern in the Korea railway sector is that low scheduled speeds contrast with the highspeed railway system design. Research design, data, and methodology – Current literature and foreign cases are analyzed. Subsequently, using data from the Korean Railroad Research Institute, a benefit analysis is conducted based on expanded track capacity and the saving of time owing to the introduction of the express highspeed railway. Result – The express highspeed railway system is expected to increase the number of train lines from 262 to 348 and the scheduled speed from 168.3km/h to 192.2km/h. Considering reduced time value, the economic effect is about 80 million won per year. Conclusion – The findings suggest that the express highspeed railway is a promising option to improve efficiency and increase customer utility. This study contributes to the literature by initiating a discussion on the express system in Korea; practically, it offers railway operators guidelines for improving highspeed railway system efficiency that can be transformed into a variety of marketing options.

Modeling and Analysing the Explosive Spalling Effect of High Fire-resistance and High-strength Concrete

SungWook Kang,HyungJae Moon,JeongJin Kim,SoonJeon Park,JooHo Lee,JooHwan Ko 한국콘크리트학회 2010 한국콘크리트학회 학술대회 논문집 Vol.2010 No.11

Benefits of Early Stakeholder Involvement in Korean Railway Infrastructure Project

SungWook KANG,DongHee KIM,JaeKyun YU,KyungChul LEE,DaeSup MOON 국제융합경영학회 2021 융합경영연구 Vol.9 No.5

Purpose: In the Korean railway infrastructure process, contractors and operators are involved at a later stage, which results in significant inefficiency. This study examines the benefits of early stakeholder involvement in Korean railway infrastructure projects and provides practical guidelines. Design, data and methodology: Literatures and foreign cases are analyzed. Building on the new product development model, we derive propositions explaining the relationship between early stakeholder involvement and the performance of Korean railway infrastructure project. Results: Major propositions include that early involvement of contractor has a positive effect on the project performance by shortening the infrastructure construction period and that early involvement of railway operator has a positive effect on the project performance by improving the effectiveness of railway infrastructure. Four requirements for the success of early stakeholder involvement are addressed. Conclusions: This study suggests that early stakeholder involvement shortens the construction period and improves railway infrastructure effectiveness. Academic contribution is to present the framework on railway infrastructure projects as holistic interactions among stakeholders. Practical contribution is to provide railway policy makers and other business practitioners with policy guidelines to improve railway infrastructure project process and to recommend an open access to relevant data.

The Effect of Unobservable Efforts on Contractual Efficiency

Sungwook Kang,Hongsuk Yang 한국경영과학회 2013 Management Science and Financial Engineering Vol.19 No.2

An interesting puzzle in business practices is that although many researchers emphasize the benefits of a revenue-sharing contract, a wholesale contract has remained to be the most common contractual form. By introducing the concept of unobservable efforts, we examine the contractual efficiency of a wholesale contract and a revenue-sharing contract. The multi-task agency model and experimental design approach are used to analyze the relationship between the contractual efficiency and parameters. A major finding of our study is that a wholesale contract coordinates unobservable efforts, while it fails to coordinate the order quantity decision. Because unobservable efforts have mixed effects on the contractual efficiency, the superiority of contract type depends on parameters. This finding implies that a wholesale contract can be a competitive contract, especially when unobservable efforts are heavily involved. Our conclusion is that the current popularity of a wholesale contract is manager’s rational response to complex supply chain environments rather than irrational behaviors.

중소기업 혁신역량과 기술개발사업에 대한 연구

강성욱(SungWook Kang),이기훈(Ki-Hoon Lee) 피터드러커 소사이어티 2011 창조와 혁신 Vol.4 No.2

본 연구는 국내 부품소재산업 중소기업들을 대상으로 기술개발 사업의 중단 및 실패요인에 대한 분석을 통해 정부정책의 효율성과 해당 기업들의 필요 요인을 파악하는데 그 목적이 있다. 특히 산업의 가치사슬에서 상류 및 하류 중간에 위치한 부품소재산업은 국내 산업의 경쟁력에 큰 영향을 미치는 특수한 산업임에도 불구하고 아직 많은 연구가 이루어지지 않았다. 또한 기존 문헌연구들이 대부분 설문조사에 기초한 기술혁신과 기술사업 또는 기술혁신과 시장지향성에 대한 인과관계를 밝히는데 집중한 반면, 실제 기술개발의 성공 및 실패에 영향을 미치는 사례연구가 거의 없는 실정이다. 본 연구는 사례연구 방법론을 활용하여, 45개 국내 부품소재산업 중소기업에 대한 3가지 요인(기술적 요인, 경영적 요인, 그리고 기타 요인)을 구분하여 파악하였다. 기술적 요인으로는 기술적 문제, 주요 연구인력 퇴사, 주요 설비 매각, 특허 문제 등이 파악되었고, 경영적 요인으로 유동성, 자본잠식, 적자, 및 부도폐업, 기타 요인으로 윤리적인 문제(임원 사기횡령 및 연구비 유용), 시장트렌드의 변화에 따른 상용화 불명확 또는 포기 등이었다. 기존에는 주로 기술적인 요인에 대한 평가를 통해 성공과 실패를 평가하였으나 본 연구를 통해 복합적인 접근을 통한 기술혁신 및 개발사업에 대한 평가를 통해 종합적인 평가를 실행하는 것이 해당사업의 성공, 중단 및 실패에 대한 의미있는 평가를 이룰 수 있다. 또한 부품소재산업의 특성만으로 본 연구결과를 일반화하는데 한계가 있으므로, 상하위 산업에 대한 연구도 향후 진행함으로써 기술적, 경영적, 그리고 기타요인을 파악함으로써 본 연구결과의 유의성을 높일 수 있다. In spite of the widespread recognition of the important roles that innovative, technology-oriented small and medium sized enterprises (SMEs) play in most economies, limited research has focused on the integrated aspects of technology, management and the related factors. Since there are no well-defined or established research models or frameworks, we adopted an exploratory case approach to investigate key factors that affect success and failure business cases in the Korean components and materials industry. With forty-five case study analysis, we found that there are three important factors of business successes or failures with technology-oriented SMEs. These include technology factors (market-oriented technology; timely innovative technology; technology innovation capability; patents), management factors (financial resource; management commitments; human resource; R&D capability; commercialization capability), and the related factors (top managers’ ethical issues; transparency in R&D budgets; lack of commitments for success). For better understanding on the roles of the factors with SMEs, we put an emphasis on the integrative approach which combines technology, management, and the related factors to examine successful or failing business cases. Further studies will benefit from our findings to develop theoretical models and examine other industries.

네트워크 디스크를 공유하여 SQL 서버의 대용량 스토리지 확보 방법 - Amazon EC2 Windows 환경에서 -

강성욱 ( Sungwook Kang ),최종선 ( Jungsun Choi ),최재영 ( Jaeyoung Choi ) 한국인터넷정보학회 2016 인터넷정보학회논문지 Vol.17 No.2

클라우드 컴퓨팅 환경에서 사용자는 중앙처리장치, 메모리, 네트워크, 저장 장치 등과 같은 인프라를 IaaS(Infrastructure as a Service) 서비스로 제공받을 수 있다. 저장 장치의 경우 서비스 제공자가 제공하는 물리적인 자원들의 인스턴스가 제공하는 저장 용량이 제한되어 있으므로, SQL 서버가 사용할 수 있는 최대 저장 용량을 지원할 수 없다. 본 논문에서는 한정된 용량을 가진 인스턴스들의 네트워크 디스크를 공유하여 SQL 서버에서 사용할 수 있는 대용량의 저장소를 확보하기 위한 방법을 제안한다. 실험을 통해 아마존 EC2 윈도우즈 환경에서 아마존 EBS 볼륨을 사용하는 하나의 인스턴스가 사용할 수 있는 최대 저장 용량을 초과하는 대용량 저장 공간을 확보할 수 있으며, SQL Server를 운영하는 아마존 클라우드 환경에서 디스크 용량 및 성능을 증가시켜 전체적인 SQL Server의 성능을 향상시킬 수 있음을 확인하였다. Users are provided infrastructure such as CPU, memory, network, and storage as IaaS (Infrastructure as a Service) service on cloud computing environments. However storage instances cannot support the maximum storage capacity that SQL servers can use, because the capacity of instances provided by service providers is usually limited. In this paper, we propose a method of securing mass storage capacity for SQL servers by sharing network disks with limited storage capacity. We confirmed through experiments that it is possible to secure mass storage capacity, which exceeds the maximum storage capacity provided by an instance with Amazon EBS on Amazon EC2 Windows environments, and it is possible to improve the overall performance of the SQL servers by increasing the disk capacity and performance.

Symbolic Transfer Entropy 를 이용한 왼손/오른손 상상 움직임에서의 특징 추출

강성욱(Sungwook Kang),전성찬(Sung Chan Jun) 한국정보과학회 2010 한국정보과학회 학술발표논문집 Vol.37 No.2A

강섬유 혼입 콘크리트의 방폭성능 해석연구

강성욱(Kang, SungWook),신재경(Shin, JaeKyoung),박종호(Park, JongHo),김정진(Kim, JungJin),이주호(Lee, JooHo),고주환(Koo, JooHwan) 한국콘크리트학회 2011 한국콘크리트학회 학술대회 논문집 Vol.2011 No.5

인공신경망을 활용한 차량 오버스티어 예측

강성욱(Sungwook Kang),김민지(Minji Kim),이요셉(Joseph Lee),유승한(Seung-Han You) 대한기계학회 2023 대한기계학회 춘추학술대회 Vol.2023 No.4