풍력발전기 운전환경에 따른 진동신호 분포

신성환,김상렬,서윤호,Shin, Sung-Hwan,Kim, SangRyul,Seo, Yun-Ho 한국음향학회 2016 韓國音響學會誌 Vol.35 No.3

풍력발전설비는 접근성의 문제로 주기적인 구조건전성 검사를 수행하기 어렵고, 기상상태를 포함한 주위 환경변화 때문에 예기치 못한 고장발생 가능성이 높아 이에 대한 보완책으로 상태감시시스템(Condition Monitoring System, CMS)을 운영하고 있다. 본 연구에서는 CMS의 이상감시 성능 향상을 위하여 풍력발전기 주요 기계시스템에서 장기간 측정된 진동신호 분포를 통계적으로 분석하고, 운전 조건에 따른 진동 변화 경향을 파악한다. 이를 위하여, 풍력발전기 동력전달 및 전력생성부의 진동, 풍속, 주축회전수 등을 약 2년동안 측정한 데이터를 기반으로 운전 환경 및 조건에 따른 각 신호의 경향분석을 수행하고, 기계시스템 구조에 따른 신호별 상호연관성을 분석하였다. 결과적으로 풍력발전기 기계시스템별 진동은 주축회전수, 발전여부에 영향을 받고, 특정 주축회전수에서는 베이불(Weibull) 분포에 해당하는 진동분포가 나타남을 확인하였다. 이런 결과는 풍력발전기 CMS 시스템에서 기계적 이상발생 여부를 조기에 판단하는 기준을 제시할 수 있다. Condition Monitoring System (CMS) has been used to detect unexpected faults of wind turbine caused by the abrupt change of circumstances or the aging of its mechanical part. In fact, it is a very hard work to do regular inspection for its maintenance because wind turbine is located on the mountaintop or sea. The purpose of this study is to find out distribution patterns of vibration signals measured from the main mechanical parts of wind turbine according to its operation condition. To this end, acceleration signals of main bearing, gearbox, generator, wind speed, rotational speed, etc were measured through the long period more than 2 years and trend analyses on each signal were conducted as a function of the rotational speed. In addition, correlation analysis among the signals was done to grasp the relation between mechanical parts. As a result, the vibrations were dependent on the rotational speed of main shaft and whether power was generated or not, and their distributions at a specific rotational speed could be approximated to Weibull distribution. It was also investigated that the vibration at main bearing was correlated with vibration at gearbox each other, whereas vibration at generator should be dealt with individually because of generating mechanism. These results can be used for improving performance of CMS that early detects the mechanical abnormality of wind turbine.

영상디지털도어록용 단일 사람 검출 알고리즘 구현

신성환,이상락,최한고,Shin, Seung-Hwan,Lee, Sang-Rak,Choi, Han-Go 한국정보처리학회 2012 정보처리학회논문지B Vol.19 No.2

영상디지털도어록(Video digital door lock, VDDL) 시스템은 문으로 출입하는 사람을 검출하고 사람 영상을 획득한다. 도어록 설계 시 고려할 사항은 배터리 기반으로 동작하므로 속도가 빠른 사람 검출 알고리즘을 적용하여 전류소모를 최소화해야 한다. 그리고 도어록은 고정된 카메라에서 영상을 촬영하므로 배경영상을 이용한 사람 검출이 높은 신뢰성을 얻을 수 있다. 본 논문에서는 이러한 요구조건에 충족하며 VDDL에 적합한 단일 사람검출 알고리즘을 다루고 있는데, 획득한 영상에서 이동하는 물체를 감지하고 영상처리를 통해 물체가 사람인지를 판별한다. 제안된 영상처리 알고리즘은 두 단계로 이루어져 있다. 첫째, 배경영상과 피부색 정보를 통해 사람 이미지 영역을 구한다. 둘째, 인체비례 정보를 기반으로 폴라 히스토그램을 이용하여 사람 유무를 판단한다. 개발된 알고리즘은 도어록에 설치하고 실험을 통해 성능을 확인하였다. Video digital door lock(VDDL) system detects people who access to the door and acquires the human image. Design considerations is that current consumption must be minimized by applying fast human detection algorithm because of battery-based operation. Since the digital door lock takes an image through a fixed camera, detection of a person based on background image leads to high degree of reliability. This paper deals with a single human detection algorithm suitable for VDDL with fulfilling these requirements such that it detects a moving object in an image, then identifies whether the object is a person or not using image processing. The proposed image processing algorithm consists of two steps: Firstly, it detects the human image region using both background image and skin color information. Secondly, it identifies the person using polar histogram based on proportional information of human body. Proposed algorithm is implemented in VDDL and is verified the performance through experiments.

스피커의 주관적 청음 평가치와 라우드니스 측정치 간의 상관 관계

신성환,이정권,정혁,유동구,Shin, Sung-Hwan,Ih, Jeong-Guon,Jeong, Hyuk,Yu, Dong-Gu 한국음향학회 2000 韓國音響學會誌 Vol.19 No.7

스피커의 음질에 대한 재생 성능을 판단하기 위하여 개발 및 최종 평가 단계에서 수행되는 청음실험은 시간과 경제적 문제뿐만 아니라, 평가자의 평가 능력에 따른 재현성 및 신뢰성에 많은 문제를 나타낸다. 이와 같은 이유로 스피커의 성능은 주관적 평가치 뿐만 아니라 객관적인 지표로서도 나타내는 시도가 함께 이루어져야 한다. 이를 위한 시도의 하나로서, 본 연구에서는 청음실험 및 통계 처리를 실행하여 얻은 주관적 평가 결과와 스피커 재생음에 대한 음질인자 해석을 통하여 얻은 객관적 측정 사이의 관계를 밝히고자 한다. 청음실험 결과는 분산분석법 및 Tukey의 방법을 이용한 네 단계의 통계 처리를 통하여 주관적 평가 결과를 얻고, 객관적 평가를 위해서는 라우드니스 측정을 기본으로 한 충실도 평가치 (Fidelity Rating)와 부드러움 평가치 (Softness Rating)를 제안한 후, 두 평가 결과의 상관도를 계산함으로써 타당성을 검증하였다. 본 연구에서의 방법론을 이용하면, 개발품 및 완성품의 스피커 음질 평가에 있어서, 시간이 많이 들고 비싼 주관 평가 작업이 없이도 통계적으로 안정되게 예측 평가할 수 있다고 본다. Acoustic performance of loudspeakers for sound reproduction has been qualitatively evaluated by using the listening test by juries in the development and final evaluation stages. However, the subjective evaluation method has many problems in the viewpoint of reliability and repeatability that are mainly related to the jury performance, as well as time and economy. In this reason, objective techniques should be tried to evaluate the acoustic performance of loudspeakers as well as the conventional subjective test. The object of this study is to find if there is any correlation between the statistically treated in test results and the measured results based on the loudness of reproduced sound signals. For the four-step statistical analysis, the analysis of variance (ANOVA) and Tukeys method are employed for dealing with the data from the listening test. For the objective evaluation, Zwickers loudness considering the human hearing characteristics is calculated for the measured sound signal emitted from each loudspeaker and the objective ratings such as fidelity rating (FR) and softness rating (SR) is suggested. The correlation between two ratings has been demonstrated for an actual set of loudspeakers using FR, SR and correlation coefficient. The method in this study can be useful in statistically evaluating commercial or prototype loudspeakers without using very time-consuming and expensive subjective testing.

민간투자사업 수요위험 분담 방식에 관한 연구

신성환,Shin, Sung-Hwan 한국건설관리학회 2012 한국건설관리학회 논문집 Vol.13 No.2

민간투자사업의 핵심 성공요인은 민간사업자와 정부 간의 적절한 위험 분담과 민간사업자가 부담하는 위험 대비 적절한 수익의 제공이다. 현재 국내 민간투자사업은 민간사업자가 대부분의 위험을 부담하는 수익형 민자사업(BTO)과 정부가 대부분의 위험을 부담하는 임대형 민자사업(BTL)로 구분되어 있을 뿐, 정부와 민간사업자가 위험을 다양한 형태로 분담하는 방식은 아직 도입되어 있지 않은 상태이다. 이 결과 도로, 항만 등 수익형 민간투자사업 방식으로 진행되는 사업에 대한 과다한 위험부담으로 인해 민간사업자의 수익형 민간투자사업에의 참여가 극도로 저조한 상황이다. 본 연구에서는 민간투자사업 위험 중 가장 큰 위험인 수요위험(demand risk)을 정부와 민간사업자가 분담하는 새로운 방식의 민간투자사업을 살펴보고자 한다. 보다 구체적으로 본 연구에서는 민간투자사업의 운영수입을 모두 정부에 귀속시킨 후 운영수입 수준에 따라 민간사업자에게 계단형으로 지급되는 방식을 살펴보고자 한다. 민간사업자가 부담하는 위험 대비 적절한 수준의 정부지급금을 실물옵션 모형 및 위험중립적(risk neutral) 방법론을 통해 산출하고, 산출된 구간별 정부지급금에 반영된 사업수익률을 추정하고자 한다. 본 연구에서 사용한 방법론 및 결과는 향후 국내에 다양한 방식의 민간투자사업이 도입되는데 도움을 줄 수 있을 뿐만 아니라, 민간이 제시하는 다양한 방식에 대한 평가 기준을 설정하는데 도움을 줄 수 있을 것으로 기대된다. One of key success factors in PPI(Public Private Investment) is the structure of risk sharing between the public and the private, and the determination mechanism of fair return to private participants relative to the risk that private participants undertake. In Korea, two basic types of PPI exist. One is BTO and the other is BTL. In BTO, most risks are taken by the private whereas the opposite is the case in BTL. No intermediate form exists. As a result, BTO type projects had difficulty in attracting private participants because of the excessive risks. In this study, one intermediate form is studied where demand risk is shared between the public and the private. In the setting where the public authority takes all the project revenues and then pays ladder type payments to private participants depending upon the level of project revenues, appropriate level of fixed payments is endogenously derived using the real option pricing model. From the fixed payments, expected investment returns are calculated based upon a certain distributional assumption. The results of this study is expected to help introducing diverse forms of PPI in Korea.

차수 스펙트럼 변화를 통한 차실내부 음질 향상

신성환,Shin, Sung-Hwan,Hashimoto, Takeo 한국음향학회 2013 韓國音響學會誌 Vol.32 No.4

자동차 엔진을 포함한 구동계 및 흡배기계 소음의 특징은 차수 스펙트럼(order spectrum) 분석으로 파악할 수 있다. 기존의 선행 연구에서는 엔진의 1차 및 2차 점화주파수(firing frequency)와 관련된 차수성분이 차실내부 소음에 주요한 영향을 미치는 것으로 알려져 있다. 본 연구에서는 차수스펙트럼의 변환에 따른 차실내부 소음의 음질(쾌적감) 차이를 파악하고자 한다. 이를 위하여 6실린더 및 4실린더 가솔린 엔진을 가진 승용차의 차실 내부 소음을 측정하고, 이 소음에 적응형 디지털 필터(adaptive digital filter)를 적용하여 차수레벨을 가감하는 방법으로 수정한다. 쌍비교법을 이용한 청음실험을 통하여 원음 및 편집음의 음질 정도를 평가하고, 음질 향상을 위한 차수스펙트럼 변화 방향을 제시한다. 결과적으로 반-차수(half-order) 성분의 차수레벨 감소가 차실내부 소음의 쾌적감 향상에 영향을 주는 반면, 점화차수 레벨의 감소가 항상 음질에 긍정적인 영향을 주는 것은 아님을 파악하였다. Order spectrum analysis is widely used to grasp the features of noises due to powertrain system including engine and intake/exhaust system. It is known from many previous researches that order components related to the first and second firing frequencies of engine considerably affect the noise of car interior. The purpose of this paper is to find out the difference in sound quality: Pleasantness of car interior noise according to the change of its order spectrum. For this, car interior noises of 6-cylinder and 4-cylinder engines are recorded and their order spectrum levels are modified by applying adaptive digital filters. After subjective listening test employing paired comparison method is conducted, it is investigated that the level change of half-order components is a noticeable factor to improve Pleasantness of the car interior noises whereas level decrease of firing order does not always give the positive effect on its sound quality.

BTO 민간투자사업 해지시지급금 매수청구권 가치에 관한 연구

신성환,Shin, Sung-Hwan 한국건설관리학회 2011 한국건설관리학회 논문집 Vol.12 No.3

Real option values of early termination payment for selected BTO PPI projects are studied using binomial models. Two cases of early termination payments are considered; an option with the condition of private participants' default, and an option without the condition. Values vary depending upon parameter values such as revenues, costs, discount rates, debt ratio, and volatility of revenues. For selected projects, the option values without the default condition are estimated as 1%~7% of total project costs, whereas the option values with the default condition are estimated as 0%~1.89% of total project cost. When actual revenues differ from the forecasted revenues, apparently the option values deviate from the values based upon the forecasted revenues. When actual revenues fall short of the forecasted revenues, the option values increase by a large amount whereas the option values decrease by a small amount in the opposite case. This implies that the option values can be quite bigger than the values based upon the forecasted revenue especially when the revenue forecast uncertainty is large. This study is expected to play an important role in improving the early termination payment option policy of the government in PPI projects in Korea. 본 논문에서는 민간투자사업에서 사업시행자가 보유하고 있는 해지시지급금에 대한 매수청구권의 가치를 이항모형을 통한 실물옵션 가치추정 방법론을 사용하여 추정하였다. 매수청구권은 사업시행자의 부도조건부 매수청구권과 부도조건이 없는 매수청구권으로 구분하여 가치를 추정하였고, 해지시지급금은 사업자귀책인 경우의 금액으로 가정하였다. 운영수입, 운영비용, 사업수익률, 부채비율, 운영수입의 변동성 등에 따라 매수청구권의 가치는 달라지는데, 부도조건이 없는 매수청구권 가치는 대략 총사업비의 1%~7% 수준으로 추정되었고 부도조건부 매수청구권의 경우 0%~1.89% 수준으로 추정되었다. 민간투자사업의 수요예측위험의 영향을 파악하기 위해 실제 운영수입이 예상수입과 다른 경우의 매수청구권 가치도 추정하였다. 실제 운영수입이 예상수입에 못 미치는 경우 매수청구권 가치는 큰 폭으로 상승하는 반면 반대의 경우는 매수청구권 가치가 소폭 하락하는 것으로 추정되었다. 이는 수요예측의 불확실성이 큰 경우 실시협약 시점에서의 매수청구권 가치는 예상수입을 가정한 매수청구권 가치보다 상당히 클 수 있다는 점을 의미한다. 본 논문은 향후 해지시지급금 제도를 개선하는데 기여할 수 있을 것으로 기대된다.

17세기 재지사족의 향촌질서 재편과 <전가팔곡>

신성환 ( Seong Hwan Shin ) 우리어문학회 2015 우리어문연구 Vol.52 No.-

The purpose of this thesis is to thoroughly review how to create <Jeongapalkock> by Johnje I Hui-Il(1619~1672) and achieve a new direction of understanding of this work. In order to do that, it needs to examine the way to found and run the country order since I Hui-il had settled down in Jeogock. At that time, those who lived in Jeogock were the lower class. I Hui-Il unified the lower class into a community as nobility. He organized Ochondonggye which is a community combined the upper and lower classes together and tried to maintain the country order stably through education and aid. He was also positive to be a farmer, and interested in agricultural management such as soil fertility. Even though, He was not a farmer himself, but he thought very highly of agriculture. It seems that he would participate farming as a supervisor rather than a farmer in Ochondonggye. <Jeongapalkock> is closely related with his life in Jeogock. It is because it was created only a month before he made 「Onchondonggyeseo」 and the official title of this poem is <Jeogockjeongapalkock>. It consists of 8 stanza which are about 4 seasons and day and night. It is distinguished from other poems by two different speaker in one poem. One is a farmer as a laborer, and the other is a farmer as a supervisor. This is a result that the author spent 3 years in Jeogock organizing Ochondonggye as a community combined the upper and lower classes together. In other words, <Jeongapalkock> is a reflection of his ideal community that everyone participates agriculture in accordance with one’s own position. He did not stop just to create a poem. He knew that the lower class would not understand his will. That is why he made children sing his poem in order to learn his idea naturally.

근대 도시 미로(迷路) 에 대한 오랜 꿈의 실현과 좌절

신성환 ( Sung Hwan Shin ) 한국언어문화학회 2010 한국언어문화 Vol.0 No.42

This study was aimed at analysizing the diverse aspects of new self-consciousness of modern city-space, creating shapes of detective. In detective novels, detective have good command of demanding inductive reasoning and scientific knowledge to solve the crimes, because they had been based on the genre pattern of the western classical detective novels. The strained relations between inductive reasoning and crimes, is valid for crime-space. This study makes a feature of emphasizing the way one thinks of insight not the representations of modern city-space in 〈Ma-In〉. The number of crimes in 1930`s Gyengsong is on the increase, variety of provinces of the modernity be piled up one on another. It is no accident that detective novel is coeval with the construction of the new housing form in modern city. The shape of detective is entirely the product of modern city. First, on the theory of Tuan, figuratively speaking, `space` means movement, opening and threat, on the other hand, `place` means quiescence, safety and stability. That`s detective`s share of work to convert space to place through reveal a secret of space. 〈Ma-In〉`s main character, Yu-Bulan, conceiving detective, communes with city-space in the concrete. He traced not only city`s surface but also city`s glittering facade, makes a strong appearance of the `Flaneuse`, collector, thinking machine, is defined as an his ability to figures out the cryptic clues with independent rationality and individuality. However, the Japanese colonial period in the 1930`s, physical conditions of modern city is allowed as a mere formality, but practical experience and edifice, `substance of place`, is in poor condition. As a major text, Gyengsong that is no such thing as a purely specific origin and identity, that could well are very disorderly to decipherthe codes of space elements. Both writer and main character are searching not only for reality, but what lies beyond this, because so many things in their own age has failed them. Korean detective novels in the 1930`s was fated to be on the horns of a dilemma that be enforced to engages in creative writing on poor setting of the story. This study tries to display the distinctive feature of the detective novels in the 1930`s through the analysis of 〈Ma-In〉. To study this character of 〈Ma-In〉 can be a try to find the identity of Korean detective novels. The readers can find out features of the Korean detective novel through the indigenous detective novel in 1930`s. In conclusion, 〈Ma-In〉 is the story of `detective of end in failure`. Detective can`t rescue the a lot of victims, not find out crime-tricks. In some way, it is natural for him to failure, because space of 〈Ma-In〉 is made up transcendental cognition.

ALM 분석을 통한 국민연금 적립금 목표수익률에 대한 연구

신성환 ( Sung Hwan Shin ) 한국금융학회 2010 금융연구 Vol.24 No.1

국민연금 제도는 우리나라 사회보장 제도의 근간을 이루는 중요한 제도로서 적립방식과 부과방식의 중간적인 형태인 부분적립방식으로 운영되고 있다. 국민연금 제도가 시행된 지 아직 초기 단계이기 때문에 적립금 규모는 매우 빠른 속도로 증가하고 있는 반면, 인구구조의 변화로 인해 국민연금 적립금은 제도개혁이나 적립금 운용수익률의 개선 없이는 2060년경에 고갈될 것으로 예상된다. 국민연금에서 자체 분석한 추계자료에 따르면 적립금이 고갈되어 부과방식으로 전환되는 경우 보험료율은 무려 임금의 24%에 달할 것으로 예상된다. 본 연구에서는 국민연금 재정안정화를 ‘적립금규모/총임금’ 비율이 시간에 따라 일정하게 유지되는 상태로 정의하고, 이를 달성할 수 있는 적립금 운용 목표수익률 및 보험료율 정책에 대하여 분석하였다. 본 연구의 결과를 간략히 요약하면 다음과 같다. 첫째 국민연금이 연 평균 5.29%의 운용수익률을 달성할 경우 국민연금 적립금은 현행 제도 하에서 2060년 고갈되는 것으로 예상된다. 둘째 2078년 이후의 적립금 운용 기대수익률이 6%라고 가정할 때, 2078년까지 재정안정화를 이룰 수 있는 2078년까지의 연간 적립금 운용 기대수익률과 보험료율의 조합은 (6%, 12.3%), (7%, 10.2%), (7.5%, 9.2%) 등으로 도출되었다. 셋째, 5% 확률로 발생 가능한 저조한 수익이 실현될 경우 2078년까지의 남은 기간 동안 재정안정화를 기대할 수 있기 위한 보험료 인상 폭이라고 정의할 때, 기대수익률에 수반되는 보험료율 인상 위험은 (6%, 0.7%), (7%, 1.1%), (7.5%, 1.4%)로 분석되었다. 비록 본 연구의 분석결과가 2078년까지의 장기 재정추계에 의존한다는 단점을 갖고 있기는 하나 본 연구에서 분석한 내용들이 재정추계값이 변화함에 따라 정기적으로 재검토 되고 조정될 경우 국민연금 적립금은 국민연금 재정을 장기적으로 안정화시킬 수 있는 방향으로 운용될 수 있을 것이다. Korean national pension system (KNPS), as a back bone of the nation`s social security system, is a partially funded system that has the characteristics of both funded and pay as you go systems. Because KNPS is a relatively young system which started in year 1988, the fund size of KNPS is currently increasing rather rapidly. Due to unfavorable demographic changes, however, the fund is projected to be depleted by year 2060 if KNPS is not reformed. According to the projection data by Korean national pension research center (KNPRC), the contribution rate will be as high as 24% after year 2060 when the fund is depleted and the current system is converted into pay as you go system as a result of the depletion. In this study, required fund returns and contribution rates are analysed for achieving steady state by year 2078. As a definition of the steady state, three criteria are compared; funded ratio, constant fund to pension payment ratio, and constant fund to total wage ratio. Among them, the constant fund to total wage ratio selected as a criteria in this study because it captures the characteristics of a partially funded system and it reflects the changes of liability well. As the fund return is higher, the steady state fund to total wage ratio becomes lower. So is also the case for contribution rate. According to the analysis of this study, the required fund size for the KNPS fund to reach the steady state in year 2078 is more than four times larger if the perpetual expected fund return is 4% compared with the case of 8% perpetual expected fund return. As for the contribution rate, the required fund size is more than double if the contribution rate is 9% compared with the case of 17% contribution rate. In this study, as reflected in the projection data by KNPRC, it is assumed that the wage increase ratio and the payment to total wage ratio are stabilized at 2.8% and 0.24 after year 2078, respectively. The main results are 1) the implied annual average fund return underlying the projection of KNPS fund depletion in year 2060 is 5.29% per annum, 2) if the perpetual fund return after year 2078 is 6%, the expected fund return and contribution rate combinations that can achieve the steady state by year 2078 are (6%, 12.3%), (7%, 10.2%), (7.5%, 9.2%), 3) when the risk is defined as the required contribution rate increase after five years for achieving the steady state by year 2078 under the scenario that 5% probability worst case return is realized for five years, the expected return and risk combinations are (6%, 0.7%), (7%, 1.1%), and (7.5%, 1.4%). These results have several important implications. First, there is a trade off between the expected fund return and the required contribution rate for achieving the steady state. Increasing the expected annual fund return by one percent until year 2078 is more effective than increasing the contribution rate by 2%. Second, the higher the expected fund return is, the higher the required contribution rate increase is in unlucky situations. Finally, KNPS`s depletion problem can be significantly mitigated at the current contribution rate of 9% if the average annual fund return of 7.5% can be achieved until year 2078. Target returns for KNPS fund can be determined in the coordinates of (expected fund return, required contribution rate, risk of contribution rate increase) for achieving the steady state by year 2078. The results of this study imply that setting up a target return and contribution policy is an evolutionary process. As demographics change and the realized future returns are different from the expected fund returns, contribution rate needs to be adapted to the change. Sometimes, even target returns may need to change depending upon the feasible set of contribution policy. This study has a limitation that it is based upon the projection data by KNPS research center. Nonetheless this study will help KNPS set its investment policy from the perspective of long-term sustainability of KNPS. In this way, it will be easier to form a consensus among interested parties of KNPS, that are government, current generations, and the future generations.

한국 소설에 나타난 부재의 기억에 대한 상상력

신성환 ( Sung Hwan Shin ) 한국언어문화학회 2015 한국언어문화 Vol.0 No.58

This study exploresthe way which Korean novels remember Sewolho catastrophe. This disaster has left deep scars to the survivors, bereaved families, officials as well as most of the Korean who witnessed the sinking of the Sewolho in real time and it’s still ongoing tragedy. This painful accident definitely exposed problems in our society. The society and people try their best to not forgetting the Sewolho catastrophe and keep looking many other ways to remember. The purpose of this study is to analyze, through the sociocultural mechanism of ‘memory’ in the perspective of Sewolho catastrophe, the structural contradictions of the current Korean society, and to go looking for the solution with the human empathy ability as the center. This study is to explain the meaning of Sewolho catastrophe as a motif or a subject matter in a Korean novels. This study is focused on four novels published recently. These novels aims to rethink and redefine the serious question of Korean society sinking with the Sewolho by taking ‘memory and oblivion’ into literary consideration. Sewolho catastrophe as a subject matter present profound cognitive issues of mourning and memory in recent years. These novels have adopted various types and forms of memory-related approach. Korean society need art of memory against forgetting after the Sewolho catastrophe. Literature today is after all an endless antagonism and discontented negotiation between the standard edition of public record accredited from the above and the renewed edition of resistant anti-memory.