신뢰성 기반 최적설계를 이용한 130m급 고정식 해양구조물 최적설계 개발

김현석,김현성,박병재,이강수,Kim, Hyun-Seok,Kim, Hyun-Sung,Park, Byoungjae,Lee, Kangsu 한국전산구조공학회 2021 한국전산구조공학회논문집 Vol.34 No.5

본 연구에서는 환경, 재료 물성 및 제작 등에서의 불확실성을 고려하여 130m급 고정식 해양구조물의 신뢰성 기반 최적설계를 수행하였다. 구조물의 구조건전성을 엄밀하게 반영하기 위해 작용 및 허용 응력의 비인 UC 값을 신뢰성 해석 및 신뢰성 기반 최적설계의 제약조건으로 고려하였다. 해양구조물의 제작비용을 저감하기 위해 자켓형 지지구조물의 중량을 최소화하였다. 불확실성의 통계적 특성은 문헌 등을 참고하여 관측되거나 측정된 데이터를 기반으로 정의하였다. 자켓형 해양구조물의 신뢰성 해석과 신뢰 기반 최적설계는 부재 수가 많아 계산 부담이 큼으로 문제의 차원을 축소하기 위해 응답의 중요성을 기준으로 설계변수를 선별할 수 있는 방법을 제안한다. 또한 효율적인 계산을 위해 신뢰성 기반 최적설계를 수행하기 전 결정론적 최적설계를 먼저 수행하였다. 마지막으로, 도출된 최적설계(안)을 기존 각 급 규정 기반 설계와 안전성 및 경제성 측면에서 비교 분석하였다. In this study, a reliability-based design optimization of a 130-m class fixed-type offshore platform, to be installed in the North Sea, was carried out, while considering environmental, material, and manufacturing uncertainties to enhance its structural safety and economic aspects. For the reliability analysis, and reliability-based design optimization of the structural integrity, unity check values (defined as the ratio between working and allowable stress, for axial, bending, and shear stresses), of the members of the offshore platform were considered as constraints. Weight of the supporting jacket structure was minimized to reduce the manufacturing cost of the offshore platform. Statistical characteristics of uncertainties were defined based on observed and measured data references. Reliability analysis and reliability-based design optimization of a jacket-type offshore structure were computationally burdensome due to the large number of members; therefore, we suggested a method for variable screening, based on the importance of their output responses, to reduce the dimension of the problem. Furthermore, a deterministic design optimization was carried out prior to the reliability-based design optimization, to improve overall computational efficiency. Finally, the optimal design obtained was compared with the conventional rule-based offshore platform design in terms of safety and cost.

대학수학능력시험 수험생들의 한의과대학 진학 동기 및 한의의료에 대한 인식 조사

김현석,김휘문,김현호,Kim, Hyun-Seok,Kim, Hwimun,Kim, Hyunho 대한예방한의학회 2019 대한예방한의학회지 Vol.23 No.2

Objectives : The study was aimed to analyze the College Scholastic Ability Test (CSAT) test-takers' favor of entering Korean Medicine college and their perception toward the Korean Medicine. The study will present information that can be used for university administrator and in medical education field. Methods : A questionnaire was developed, comprising categories about the favor of entering Korean Medicine college, the experience and reason of receiving Korean Medicine healthcare treatment, and the perception toward the Korean Medicine. Face validity and content validity of the developed questionnaire were tested before survey. Then the questionnaires were distributed to 168 CSAT test-takers. Results : The most positive reason of entering Korean Medicine college is the characteristic of job, while the negative one is of the characteristic of the discipline. Respondents who answered as positive toward Korean Medicine are more than those who answered as negative. The most positive reason of receiving Korean Medicine healthcare treatment and perceiving Korean Medicine positively is because of its medical effectiveness. The most negative reason is responded as et cetera in both categories. Conclusions : The results of the survey may indicate that by promoting recent research progresses in Korean Medicine and benefits from choosing a career as medical professions, more CSAT test-takers will have positive attitude toward Korean Medicine college entrance. Also by promoting the medical effectiveness of Korean medicine to CSAT test-takers, more CSAT test-takers will receive or have positive attitude toward Korean Medicine healthcare service.

정형검증을 통한 RFID 보안프로토콜 분석 및 구현

김현석,김주배,한근희,최진영,Kim, Hyun-Seok,Kim, Ju-Bae,Han, Keun-Hee,Choi, Jin-Young 한국정보과학회 2008 정보과학회논문지 : 시스템 및 이론 Vol.35 No.7

Radio Frequency Identification(RFID: 무선주파수식별) 기술은 유비쿼터스 구조 기술의 중요한 한 부분을 이루고 있다. 태그를 이용한 모든 제품들이 이러한 서비스의 대상이 되고 있지만 불행히도 다방면에 이용되는 이면에는 사용자의 사생활과 사용자 및 판매자간의 인증문제를 이용한 서비스 공격의 대상이 되고 있다. 현재 이러한 RFID 시스템의 보안 메커니즘들은 이슈화되고 있으며 본 논문에서는 여러가지 메커니즘들 중 사생활 및 인증문제 해결을 위해 정형검증을 통한 보안프로토콜 분석 및 취약성을 수정한 프로토콜을 제안하고자 한다. 또한 제안된 프로토콜의 실현가능성을 위한 구현가능성을 언급하고자 한다. Radio Frequency Identification (RFID) technology is an important part of infrastructures in ubiquitous computing. Although all products using tags is a target of these services, these products also are a target of attacking on user privacy and services using authentication problem between user and merchant, unfortunately. Presently, it is very important about security mechanism of RFID system and in this paper, we analyze the security protocol among many kinds of mechanisms to solve privacy and authentication problem using formal verification and propose a modified novel protocol. In addition, the possibility of practical implementation for proposed protocol will be discussed.

레이저 관성항법장치 초기정렬 성능 분석

김현석,김천중,이태규,Kim, Hyun-Seok,Kim, Cheon-Joong,Lee, Tae-Gyoo 한국군사과학기술학회 2009 한국군사과학기술학회지 Vol.12 No.5

Laser Inertial Navigation System(LINS) consists of Ring Laser Gyroscopes(RLG) and accelerometers. RLG has a lock-in region in which there is zero output for input angular rates less than about 0.1deg/sec. The lock-in region is generated by the imperfect mirrors in RLG. To avoid the lock-in region, a sinusoidal motion called dither motion is applied on RLG. Therefore this dither motion is measured by RLG/accelerometer even if at a stop state. In this situation, the performance on the initial alignment of LINS can be degraded. In this paper, we analyze the performance on the initial alignment of LINS theoretically and experimentally. Analysis results include how dither motion, the pre-filter and the corner frequency in alignment loop affects the performance on the initial alignment of LINS.

신재생에너지의 온실가스감축 기여도에 따른 지역별 보급전략

김현석,Kim, Hyun Seok 경북대학교 농업과학기술연구소 2014 慶北大農學誌 Vol.32 No.4

This study examines the contribution level of greenhouse gas(GHG) emission reduction and installation costs of renewable energy facilities. The GHG emission forecasts and industrial structures in the 16 regions of Korea are then analyzed to identify the proper supply of renewable energy sources for each region. The results show that water power is the most effective and efficient renewable energy source to reduce GHG emissions, followed by sunlight, wind power, geothermal heat, and solar heat, respectively. The 16 regions are then categorized into 4 groups based on their GHG emission forecast and industrial structure: high emission and manufacturing group, low emission and manufacturing group, low emission and service group, and high emission and service group. The proper supply of renewable energy sources for each group is then determined based on the contribution level and cost efficiency of GHG emission reduction.

Reactive Magnetron Sputtering 적용 CuN_x-Cu-CuN_x 적층형 Metal Mesh 터치센서 전극 특성 연구

김현석,양성주,노경재,이성의,Kim, Hyun-Seok,Yang, Seong-Ju,Noh, Kyeong-Jae,Lee, Seong-Eui 한국전기전자재료학회 2016 전기전자재료학회논문지 Vol.29 No.7

In the present study, the $CuN_x-Cu-CuN_x$ layer the partial pressure ratio Cu metal of Ar and $N_2$ gas using a DC magnetron sputtering device, was generated by the In-situ method. $CuN_x$ layer was able to obtain a surface reflectance reduction effect from the advantages of the process and the external light. $CuN_x$ layer is gas partial pressure, DC the Power, the deposition time variable transmittance in response to the thickness and partial pressure ratio, the reflectance was measured. $Ar:N_2$ gas ratio 10:10(sccm), DC power 0.35 A, was derived Deposition time 90 sec optimum conditions. Thus, according to the optimal thickness and the composition ratio was derived surface reflectance of 20.75%. In addition, to derive the value of ${\Delta}$ Ra surface roughness of 0.467. It was derived $CuN_x$ band-gap energy of about 2.2 eV. Thus, to ensure a thickness and process conditions can be absorbed to maximize the light in a wavelength band in the visible light region. As a result, the implementation of the $12k{\Omega}$ base line resistance of using the Cu metal. This is, 5 inch Metal mesh TSP(L/S: $4/270{\mu}m$) is in the range of the reference operation.

A case of childhood relapsing/remitting multiple sclerosis and interferon β-1b treatment in a Korean patient

김현석,이원덕,이준화,조경래,Kim, Hyun Seok,Lee, Won Deok,Lee, Jun Hwa,Cho, Kyung Lae The Korean Pediatric Society 2007 Clinical and Experimental Pediatrics (CEP) Vol.50 No.6

Multiple sclerosis (MS) is a demyelinating disorder that affects discrete areas of the CNS, including the optic nerves, in a quite variable relapsing-remitting fashion over a prolonged period of time. Although MS is usually considered to be a disease that affects peoples in early to middle adulthood, children do develop multiple sclerosis. The frequency of MS onset before the age of 15 years is 2.7-5% of all cases, while MS onset during infancy and early childhood was observed to be 0.2-0.7% of all cases. We report here on a Korean case of a relapsing-remitting MS female child who was treated with four rounds of intravenous methylpredinsolone pulse therapy and preventive Interferon-$\beta$-1b ($Betaferon^{(R)}$). 다발성 경화증은 중추신경계 백질의 여러 부위를 시간 간격을 두고 침범하는 만성재발성 질환이다. 주로 20세에서 40세 사이에 발병하며 15세 이하 소아에서도 3-5% 정도 발병하는 소아기에는 매우 드문 질환이다. 원인은 아직 정확히 밝혀지지 않았으나 유전적, 환경적 및 감염과 연관된 자가면역반응 등 여러요인이 복합적으로 작용하는 것으로 생각하고 있다. 임상증상은 침범된 백질 부위에 따라 다양한데 사지근력 약화나 저림, 시력장애, 감각장애, 운동실조 등 다양한 증세로 호전과 재발을 반복한다. 본 저자들은 경련, 왼쪽 편마비 등의 증상으로 6세에 첫 발병 후 메틸프레드니솔론(methylprednisolon) 치료 후 증상 완전 회복 있었으나 6개월 후 경련, 두통, 왼쪽 안와주위 통증 등으로 다시 입원하는 등 4년간 추적 관찰 중 4차례 메틸프레드니솔론 치료 실시하였으나 다른 양상의 신경학적 증상으로 재발하여 Interferon-${\beta}$-1b($Betaferon^{(R)}$, SheringAG, Germany) 예방 치료를 실시한 다발성 경화증 환자 1례를 경험 하였기에 문헌 고찰과 함께 보고하는 바이다.

온실 내 온도와 일사량이 스프레이국화의 생육과 절화품질에 미치는 영향

김현석(Hyun Seok Kim),이광용(Kwang Yong Lee),신학기(Hak Ki Shin) 한국원예학회 2003 한국원예학회 학술발표요지 Vol.2003 No.5

한국SGI의 전개 과정과 포교 현황 -문화회관의 건립·활동을 중심으로-

김현석 ( Kim Hyun Seok ) 동서대학교 일본연구센터 2021 次世代 人文社會硏究 Vol.17 No.-

오늘날 한국 사회에서 전체 종교 신자의 수는 점점 줄어드는데 반하여, 한국 창가학회(이하‘한국SGI’ 로함)만이 성장을 계속하여 공칭 150만의 신자 수를 기록하고 있다. 한국SGI는 일본에서 1960년대 초 국내로 유입되면서 전국적으로 퍼지기 시작하였는데, 오늘날까지 다양한 성장 과정을 거치면서 활동을 지속해오고 있다. 그러나 지금까지 한국SGI의 활동은 여러 우여곡절이 있었다. 일본에서 건너온 종교라는 점에서 왜색종교로서 정부·언론과 갈등을 빚기도 하였고, 그것이 종교 내부의 분열로 연결되어서 조직을 통합하기 위한 노력이 지금도 진행되고 있기도 하다. 왜색종교라는 비난을 극복하고 공칭 150만 신자를 가진 거대 종교집단으로 성장한 한국SGI의 존재는, 한국의 종교계는 물론 한국 사회 전체에 어떤 의미로 이해되어야 하는지에 대한 물음을 제기하고 있다고 하겠다. 따라서 본 연구는, 한국SGI의 발전과정과 현(現)실태에 주목하여 종교세력으로의 성장 과정을 살피고, 종교집단으로서의 조직과 활동의 거점이 되는 문화회관의 성립과 현황을 검토하여 다음과 같은 결론을 도출하였다. 첫째, 한국SGI의 활동 거점인 문화회관은 초기 회원들의 영향으로 경상도 지역에 편중되는 경향을 보인다. 둘째, 한국SGI의 성장 과정의 성공은 문화회관의 수적 성장과 비례한다고 볼 수 있다. 셋째, 문화회관의 건립이 2017년부터 그 수가 줄어들고 있는데 이러한 현상은 한국사회 전체 종교인구의 감소와 그 흐름을 같이하기 때문에 앞으로도 지속하는 현상으로 판단된다. While the total number of religious believers in today's Korean society is decreasing, only the Korea SGI continues to grow, recording a nominal 1.5 million believers. Korea's SGI began to spread throughout the country in the early 1960s when it was introduced from Japan to Korea, and has continued its activities through various indigenousization processes to this day. however, Korea SGI's activities have had many ups and downs. The existence of Korea SGI, which has overcome criticism as a Japanese religion and has grown into a large religious group with a nominal 1.5 million believers, raises the question of what it should mean not only to the Korean religious community but also to the entire Korean society. Therefore, this study focused on the indigenousization of SGI in Korea and examined the process of growth as a religious force, and reviewed the establishment and status of cultural centers that are the base of organizations and activities as religious groups to draw the following conclusions. First, the Cultural Center, an active hub of Korea SGI, tends to be concentrated in Gyeongsang-do due to the influence of early members. Second, the success of the process of indigenousization of Korea SGI can be seen as proportional to the numerical growth of the cultural center. Third, the number of cultural centers has been decreasing since 2017, and this phenomenon is believed to continue in the future as it is in line with the decrease in the total religious population in Korean society.

단일처리 및 육묘방법이 스프레이국화의 생육과 품질에 미치는 영향

김현석(Hyun Seok Kim),권민경(Min Kyung Kwon),한윤열(Youn Yol Han),정상환(Sang Hwan Chung) 한국원예학회 2002 한국원예학회 학술발표요지 Vol.2002 No.6