Transient pressure behavior and pressure protections for LNG fuel storage tanks of large LNG-fuelled ships

Suwon Seo,Daejun Chang 한국해양환경·에너지학회 2012 한국해양환경공학회 학술대회논문집 Vol.2012 No.5

Transient pressure behavior and pressure protections for LNG fuel storage tanks of large LNG-fuelled ships

Suwon Seo,Daejun Chang 대한조선학회 2012 대한조선학회 학술대회자료집 Vol.2012 No.5

Experimental study on heating type pressurization of liquid applicable to LNG fueled shipping

Seo, Suwon,Jang, Wonhee,Kim, Juneyoung,Ryu, Jiheon,Chang, Daejun Elsevier 2017 Applied thermal engineering Vol.127 No.-

<P><B>Abstract</B></P> <P>The present experimental study investigates the pressurization effect in a fluid storage tank injected with superheated vapor. The pressurizing system re-injects high-temperature forced boil-off gas (BOG), which is emitted after heating a portion of liquid with an external heater connected to the liquid storage tank, to pressurize the liquid. The experimental equipment comprises a vertical-type pressurizing tank having a volume of 8.2liter and a mini-vaporizer that utilizes the heater. NOVEC 649 refrigerant was used. A mathematical formulation, which can effectively predict pressure rise by considering the material and energy transfer at the interface, was suggested. The experimental results indicated that the pressurizing time reduces as the initial liquid filling ratio and heat input rate increase. It was found that the actual time required to reach the target pressure can be reduced by up to approximately 1/3 the time calculated from the homogeneous model. Without considering the heat transfer via the interface, the model results of pressure rise is approximately 10% higher than the experimental value.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A pressurization effect of using superheated vapor was investigated experimentally. </LI> <LI> The experimental results were compared with the homogeneous model results. </LI> <LI> The actual pressurizing time was reduced to 1/3 the time of homogeneous model. </LI> <LI> The non-homogeneous model predicted the actual pressure rise with 3% error. </LI> </UL> </P>

Sleep Mode Detection for Smart TV using Face and Motion Detection

( Suwon Lee ),( Yong-ho Seo ) 한국인터넷정보학회 2018 KSII Transactions on Internet and Information Syst Vol.12 No.7

Sleep mode detection is a significant power management and green computing feature. However, it is difficult for televisions and smart TVs to detect deactivation events because we can use these devices without the assistance of an input device. In this paper, we propose a robust method for smart TVs to detect deactivation events based on a visual combination of face and motion detection. The results of experiments conducted indicate that the proposed method significantly reduces incorrect face detection and human absence by means of motion detection. The results also show that the proposed method is robust and effective for smart TVs to reduce power consumption.

Single-View Reconstruction of a Manhattan World from Line Segments

Lee, Suwon,Seo, Yong-Ho The Institute of Internet 2022 International journal of advanced smart convergenc Vol.11 No.1

Single-view reconstruction (SVR) is a fundamental method in computer vision. Often used for reconstructing human-made environments, the Manhattan world assumption presumes that planes in the real world exist in mutually orthogonal directions. Accordingly, this paper addresses an automatic SVR algorithm for Manhattan worlds. A method for estimating the directions of planes using graph-cut optimization is proposed. After segmenting an image from extracted line segments, the data cost function and smoothness cost function for graph-cut optimization are defined by considering the directions of the line segments and neighborhood segments. Furthermore, segments with the same depths are grouped during a depth-estimation step using a minimum spanning tree algorithm with the proposed weights. Experimental results demonstrate that, unlike previous methods, the proposed method can identify complex Manhattan structures of indoor and outdoor scenes and provide the exact boundaries and intersections of planes.

Serotype-Dependent Inhibition of Streptococcus pneumoniae Growth by Short-Chain Fatty Acids

Lim Suwon,Lee Dongwook,Jeong Sungho,Park Jeong Woo,Im Jintaek,Choi Bokeum,Gwak Donghyun,Yun Cheol-Heui,Seo Ho Seong,Han Seung Hyun 한국미생물·생명공학회 2024 Journal of microbiology and biotechnology Vol.34 No.1

Streptococcus pneumoniae (pneumococcus) is an opportunistic pathogen that can cause severe infectious diseases such as pneumonia, meningitis, and otitis media. Despite the availability of antibiotics and pneumococcal vaccines against some invasive serotypes, pneumococcal infection remains a tremendous clinical challenge due to the increasing frequency of infection by antimicrobial resistant, nonencapsulated, and/or non-vaccine serotype strains. Short-chain fatty acids (SCFAs), which are produced at various mucosal sites in the body, have potent antimicrobial activity, including inhibition of pathogen growth and/or bacterial biofilm formation. In this study, we investigated the antimicrobial activity of SCFAs (acetate, propionate, and butyrate) against various serotypes pneumococci. Propionate generally inhibited the growth of S. pneumoniae serotypes included in the pneumococcal conjugate vaccine (PCV) 13, except for serotypes 3 and 7F, though butyrate and acetate showed no or low inhibition, depending on the serotypes. Of note, butyrate showed strong inhibition against serotype 3, the most prevalent invasive strain since the introduction of the PCV. No SCFAs showed inhibitory effects against serotype 7F. Remarkably, the nonencapsulated pneumococcal strain had more sensitivity to SCFAs than encapsulated parental strains. Taken together, these results suggest that propionate showing the most potent inhibition of pneumococcal growth may be used as an alternative treatment for pneumococcal infection, and that butyrate could be used against serotype 3, which is becoming a serious threat.

Comparative analysis of a hybrid propulsion using LNG-LH₂ complying with regulations on emissions

Jeong, Jinyeong,Seo, Suwon,You, Hwalong,Chang, Daejun Elsevier 2018 International journal of hydrogen energy Vol.43 No.7

<P><B>Abstract</B></P> <P>This study proposed a liquefied natural gas (LNG)-liquid hydrogen (LH<SUB>2</SUB>) hybrid propulsion system for a 267,000 m<SUP>3</SUP> LNG carrier to be compliant with the energy efficiency design index (EEDI) requirement for CO<SUB>2</SUB> emissions from ships in the near future and evaluated the system with regard to the aspects of the EEDI, hybrid fuel ratio, installation area, safety, and economics. The system design parameters were adjusted to satisfy the EEDI of Phases 4 and 5, which were less than the current EEDI requirement by 14% and 28%, respectively. The propulsion power of 6 MW should be generated in Phase 4 from hydrogen that accounted for 3% of the total mass of LH<SUB>2</SUB> and LNG fuel. The CO<SUB>2</SUB>-free power generation in Phase 5 was increased to 13 MW, corresponding to 6% of the total fuel mass. The LH<SUB>2</SUB> price was $2.0/kg and $2.4/kg for Phases 4 and 5, respectively, to gain an economic competitiveness against the conventional LNG-based propulsion system.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The propulsion system of merchant vessels should be satisfied the enhanced environmental regulations and economics. </LI> <LI> The energy efficiency design index provides the applicable fuel ratios of LNG and LH<SUB>2</SUB> considering the environmental policy. </LI> <LI> The cold energy of LH<SUB>2</SUB> liquefied the BOG of LNG to improve the energy efficiency of the system. </LI> <LI> The life cycle analysis is applied to the economic evaluation for the hybrid propulsion systems. </LI> <LI> The breakeven price of hydrogen fuel for hybrid propulsion system is estimated. </LI> </UL> </P>

기업의 문제해결을 위한 품질경영시스템 적용사례 분석

서수원,정종필,Seo, Suwon,Jeong, Jongpil 한국인터넷방송통신학회 2018 한국인터넷방송통신학회 논문지 Vol.18 No.4

초기 창업업체 및 기술 창업 중소기업에 ISO 품질경영관리 시스템의 적용 여부에 따라 기업의 영속성에 어떤 영향을 끼치는지 확인한다. 특히 기술창업 중소기업의 품질경영관리 시스템이 전체 SYSTEM 에서 중요하게 차지하는 부분이 연구개발보다는 재무, 관리, 품질관리 부문의 경영관리 SYSTEM 적용이 중요함을 인지하고 있다. 각 사업구조별 의료기기 제작업체, 핸드폰 중개기 제작업체, 해외 중국업체이며 디젤엔진용 부품 제작업체 3개사의 성공 사례와 실패 사례 1개사를 통해 품질경영관리 SYSTEM을 적용하지 않은 업체의 문제점과 품질관리, 제품관리, 생산관리가 효율적 관리가 이루어지지 않아 생기는 재무적, 경제적, 관리적 문제점에 대해서 알아보고 그 원인에 대해서 연구하고 분석해본다. 사례 대상 업체에 품질경영관리 SYSTEM을 적용 후 부적합사항을 개선한 사례를 알아본다. 또한, 실패한 1개사를 선정 실패 사례를 통해 기업의 안정성과 영속성을 유지하기 위해 품질경영관리 SYSTEM을 적용 후 품질경영관리 매뉴얼과 절차서에 의거 실천 여부에 따라 사업의 성공과 실패가 판가름 남을 알 수 있음을 알 수 있었다. 최근 기업내부에서는 내부 심사원등을 선임하여 지속 개선활동을 시행해야 하고 기업의 발전과 영속성을 원하는 업체는 반드시 품질경영관리시스템을 반영하여야만 함을 설명한다. Identify the effects of ISO quality management system on the durability of the enterprise by applying it to early startups and small - and medium-sized enterprises. In particular, the quality management system of a technology start-up small and medium sized companies is important in applying the management system to the financial, management and quality control services rather than to research and development. The quality management system is applied to the medical equipment manufacturers, mobile phone brokers, foreign Chinese companies, and components manufacturers for diesel engines.Try it. Check the case where the quality management system has been applied to the company concerned and the nonconformities have been improved. In addition, the success of the project was determined by applying the quality control system to maintain the stability and perpetuation of the company through the case of the failed selection. The company explains that recently, it must appoint internal auditors to carry out continuous improvement activities and that those who want the development and continuity of the company must reflect the quality management system.

YONI : 객체 탐지를 위한 개선된 합동 훈련

김호(Ho Kim),이수원(Suwon Lee),서영건(Yeong Geon Seo) 한국디지털콘텐츠학회 2020 한국디지털콘텐츠학회논문지 Vol.21 No.1

에지 보정을 이용한 ORB SLAM2의 특징점 정합률 개선

이가현(Gahyun Lee),이수원(Suwon Lee),서영건(Yeong-Geon Seo) 한국디지털콘텐츠학회 2021 한국디지털콘텐츠학회논문지 Vol.22 No.1