인천음료수관리에 대한 제언

이학진 대한지방행정공제회 1970 地方行政 Vol.19 No.197

ErmSF에서 특이적으로 발견되는 N-terminal End Region의 점차적인 제거에 의한 활성에 중요한 아미노산의 규명

이학진,진형종,Lee Hak Jin,Jin Hyung Jong 한국미생물학회 2004 미생물학회지 Vol.40 No.4

ErmSF는 235 rRNA에 존재하는 $A_{2058}$에 이중메틸화(dimethylation)시킴으로써 항생제가 부착되는 것을 억제하여 미생물에게 MLS (macrolide-lincosamide-streptogramin B)항생제에 대하여 내성을 나타내게 하는 ERM계열 단백질(Erm family protein)중의 하나이다. 다른 ERM 단백질과는 달리 ErmSF는 상당히 긴 N-말단부위 (N-terminal end region, NTER)를 가지고 있고 이겻은 RNA와 잘 결합하는 것으로 알려진 arginine이 약 $25\%$를 구성 하고 있다. ErmSF로부터 점차적으로 NTER을 절단하면서 절단된 단백질의 활성을in vivo에서 검색하였다. 다른 변이단백질과는 달리 R60번째까지 제거된 변이단백질은 활성이 많이 소실된 것을 in vivo상에서 관찰하였다. 이 단백질을 대량생산하여 정제하고 in vivo상에서 그 활성을 검색한 결과 wild type 단백질에 비해 약 $98\%$의 활성이 소실된 것을 밝혔다. 이러한 사실은 R60이 메틸화되는 아데닌 (methylatable adenine)의 근처에 존재하는 RNA와 작용하여 메틸화되는 아데닌이 활성화부위에 적절히 위치하도록 하는 역할을 담당한다는 것을 암시하고 있다. ErmSF is one of the ERM proteins which transfer the methyl group to A2058 in 23S rRNA to confer the resis­tance to MLS (macrolide-lincosamide-streptogramin B) antibiotics on microorganism. Unlike other ERM pro­teins, ErmSF contains long N-terminal end region (NTER), of which $25\%$ is composed of arginine that is known to interact with RNA well. Gradual deletion of NTER leaded us to the point where mutant protein lost much of activity in vivo. Overexpressed and purified mutant protein showed much reduced activity in vitro: $2\%$ activity relative to that of wild type protein. This fact suggests that this amino acid interact with RNA close to meth­ylatable adenine to locate it at an active site properly.

MLS_B 항생제 내성인자인 ErmSF의 N-terminal 38개 아미노산 제거가 항생제 내성 효소활성에 미치는 영향

이학진,진형종,Lee, Hak Jin,Jin, Hyung Jong 한국미생물학회 2014 미생물학회지 Vol.50 No.3

ErmSF is one of the four antibiotic resistance factor proteins expressed by Streptomyces fradiae, antibiotic tylosin producer, which renders $MLS_B$ (macrolide-lincosamide-streptogramin B) antibiotic resistance through dimethylating A2058 of 23S rRNA, thereby reducing the affinity of antibiotic to ribosome. Unlike other Erm proteins, ErmSF harbors long N-terminal end region. To investigate its role in enzyme activity, mutant ErmSF deleted of 1-38 amino acids was overexpressed and activity in vivo and in vitro was observed. In vitro enzymatic assay showed that mutant protein exhibited reduced activity by 20% compared to the wild type enzyme. Due to the reduced activity of the mutant protein, cells expressing mutant protein showed weaker resistance to erythromycin than cells with wild type enzyme. Presumably, the decrease in enzyme activity was caused by the hindrance in substrate binding and (or) product release, not by defect in the methyl group transfer occurred in active site. ErmSF는 macrolide 항생물질인 tylosin을 생성하는 Streptomyces fradiae가 보유한 4개의 항생제 내성인자 단백질 중 하나로 23S rRNA의 $A_{2058}$에 dimethylation 시킴으로써 항생제가 부착되는 것을 막음으로써 그 내성을 일으킨다. ErmSF는 다른 Erm 단백질과는 달리 긴 N-terminal end region을 가지고 있어서 그 역할을 알아보기 위해 1-38번째의 아미노산을 제거한 결손변이 단백질을 고안하고 대장균에서 발현하여 그 활성을 in vivo와 in vitro에서 관찰하였다. 결손변이 단백질을 발현하는 대장균은 결손에 의한 활성저하에 기인하여 야생형 단백질을 발현하는 대장균에 비하여 항생제에 대한 내성이 손상된 것을 관찰하였다. 세포 외 in vitro에서의 활성은 야생형 ErmSF에 비하여 약 20%가 손상된 것으로 나타났다. 이렇게 관찰된 활성의 저하는 결손 변이에 의한 활성화 부위에서 일어난 결손에 의한 것이라기 보다는 기질의 부착 또는 생성물의 효소에서의 이탈 과정이 손상되어서 나타나는 것으로 사료된다.

도심 항공 모빌리티의 회전익 공력소음 해석

이학진,김시진 한국소음진동공학회 2023 소음 진동 Vol.33 No.4

A Study on the Characteristics of Media Art Based on Social Design by Daan Roosegaarde

이학진,최익서 한국공간디자인학회 2023 한국공간디자인학회논문집 Vol.18 No.6

(Background and Purpose) As a sustainable society becomes more important after COVID-19, the social role and design scope are expanding. If most of the existing designs had tangible characteristics for the purpose of economic value, now it should be expanded to non-industrial design for social value that is expressed for the public good. This study aims to suggest the future design direction for society through the influence and development potential of media art, focusing on cases in which social design is applied to media art that shares aesthetic value with technological media. (Method) As a concept analysis of design, we plan to look at changes in the scope and direction of previous designs. Next, media art's characteristics are analyzed from a media aesthetic point of view, and common elements between social design and media art's characteristics are derived. As a case study, the works of Daan Roosegaarde, a Dutch designer who realizes social design using media, are evaluated and analyzed. A case study was written by the author's evaluation based on a documentary survey. (Results) As a result of case analysis of media art based on social design, it has found that the range is expanding and interacting through characteristics of humans, environments, and media. For the expanding form, first, it is formed based on the collaboration of various experts and puts public values at the center. Second, a form of developing new materials and creating new artistic spatial through eco-friendly technology and art. Third, there is a form of conceptual art to share and apply social values through media art. (Conclusions) In this study, by analyzing media art's characteristics, the possibility of using it as a design for society and a methodology that can be continuously used were presented. First, with the rapid development of media, Intangible value is becoming important beyond visible value. Second, today, media art is applied in various forms and is used as conceptual art for public use in urban spatial, spatial creation, and social value sharing where technology development and art that affect the environment meet. Third, design has become essential if methodologies for social problems such as environment, humans, and ethics are optional. Fourth, the collaboration between the government, residents, and companies and the mutually cooperative attitude of various experts is a methodology for design sustainability in the future. So triggering in-depth study to vitalize media art based on social design is expected.

ESG 리질리언스를 기반으로 한 미디어아트 환경 조성에 관한 연구

이학진,최익서 한국공간디자인학회 2023 한국공간디자인학회논문집 Vol.18 No.3

(Background and Purpose) ESG is a concept that prioritizes non-financial outcome, such as corporation’s sustainability or social value creation, rather than prioritizing pre-existing method of financial statements by Environment, Social, Governance. We are experiencing unexpected global economic crisis from COVID-19 and as a decisive opportunity to prove that it is an era that sustainable management that is not affected by social change like ESG method, the future society will need new approach to integrate fundamental, systematic change, and various methods. So this research is based on environmental development for ESG social resilience, and put purpose on developing artistic environment through present digital era media and studying sustainable direction and method. (Method) Research range is set to be creating media art environment within cultural art range, and to examine feasibility and possibility of creating a media art environment for ESG resilience as a target sharing public value within urban space. With some cases, we will examine the applicability of ESG evaluation elements and media art characteristics, and identify the key elements and application methods which are applicable in future ESG era through creating digital media art environment. (Results) ESG’s environmental factors were applied to most of environment friendly, eco-friendly planning, environmental business, environmental management etc. Social elements were found in social responsibilities such as, community participation, community economic development, etc. Nothing except cooperation of community organization was found in the last governance element. The three functional characteristics of creating media art environment were satisfied with artistry, technology and publicity, and social characteristics were cultural role and mediating role for social development, and formation of various cooperation relationships in the process of creating media art environment. (Conclusions) The mutual cooperation, common factor of media art and ESG resilience, shows necessity of active attitude and reinforcement of method toward cooperative relationship. Based on the close relevance of environmental and social elements in ESG elements, and the necessity of activation in management structure elements, and the possibility of strengthening as activation of social cooperation method, analysis of media art characteristic is decided to be valuable method applicable in ESG society. By presenting creating media art environment for ESG resilience in this research, it is expected that contribute to the creation of a sustainable environment through environmental, social, artistic changes while wide ranges interacting in spatial planning in the future digital era.

노후수도관크리닝의 신공법

이학진,Lee, Hak-Jin 한국상하수도협회 1979 水道 Vol.17 No.-

노동이사제 등 이해관계자의 경영 참여

이학진,고희정 서울대학교 금융법센터 2021 BFL Vol.110 No.-

Wing-sails의 공력 해석과 최적 설계

이학진,조영민,최성임,권종오,안성목 한국항공우주학회 2012 한국항공우주학회 학술발표회 논문집 Vol.2012 No.11

Sailing ship은 선체 위의 wing-sails를 이용해 풍력에너지를 추력으로 얻는 친환경적인 선박이다. 본 연구에서는 고정받음각 상태에서 wing-sails 간의 상호작용 효과를 고려한 공력 해석을 수행하고, 풍향별 추력을 계산하여 최대 추력이 발생하는 풍향을 탐색한다. 공력 해석에는 3차원 압축성 N-S 지배방정식을 이용하였고, 보다 정확한 경계층 유동의 예측을 위해 혼합 격자계를 사용하였다. 공력 해석 결과, wing-sails간의 상호작용이 상대적으로 적은 풍향 90° 일 때 최대 추력이 발생하였다. 공력 해석 결과를 이용하여 wing-sails 주변의 유동특성과 상호작용의 영향을 분석한 뒤, 탈민감도 기반의 유전 알고리즘과 목적함수 계산을 대신할 크리깅 근사모델을 이용하여 주어진 환경에서 최적의 효율을 도출하는 최적 받음각을 탐색하였다. 풍향 45, 90, 135°에 대해 wing-sails 간의 상호작용 효과를 고려한 2차원 공력 최적화를 진행한 결과, wing-sails의 상호작용에 의해 풍향을 기준으로 뒤쪽 wing-sails의 받음각이 증가하는 경향성과 함께 추력이 약 7~23% 증가하였다. 이에 기인하여 3차원 wing-sails에 대한 검증을 통해 약 2~18%의 추력 증가를 도출하였다. The sailing ship is a eco-friendly vessels that using wind energy to produce the additional thrust by the hull above the wing-sails. In this study, we performed the aerodynamic analysis around wing-sails by considering the interaction of wing-sails in fixed angle of attack. The wind direction that produces the maximum thrust of wing-sails can be obtained by calculating the thrust of wing-sails with respect to the wind direction. In the aerodynamic analysis, we used three-dimensional compressible Navier-Stokes equation and hybrid grid to predict more viscous flow of boundary layer. We investigated that the maximum thrust of wing-sails at wind direction of 90 degree. After studying on the flow characteristic around wing-sails and effect of interaction, through derivative free based genetic algorithm and kriging surrogate model method to substitute a objective function evaluation we searched the optimal angle of attack that maximize the thrust of wing-sails. The result of optimization about wind direction of 45, 90 and 135 degree, we acquired about 7~23% of trust increment with trend of increasing the rear wing-sails’s angle of attack by the interaction of wing-sails. Also we confirmed the thrust enhancement of 2~18% by conducting a three-dimensional validation.

산업용 사물인터넷 기반의 재구성 가능한 제조 기술을 위한 데이터 모델

이학진,김현종,이용귀,전영애,손지연 한국정보과학회 2023 정보과학회 컴퓨팅의 실제 논문지 Vol.29 No.3

A reconfigurable production system is a manufacturing concept related to the 4th industrial revolution and can satisfy various customer needs inexpensively and flexibly. The existing production systems close an interface to the equipment included in the production line, so it is difficult to recycle existing equipment when the production line is reconfigured. To solve these problems, this study proposed a reconfigurable manufacturing technology based on the industrial internet of things architecture and data model. The reconfiguration architecture was planned and implemented in a way that can continue to use existing equipment, and the data model was based on an ISA-95 data model designed by additionally reconfiguring the fields necessary for reconfiguration. This data model and architecture solved the problem that the installer had to check the set value of the equipment directly through the data model-based equipment automatic search function and the industrial IoT-based data real-time transmission. The data model used in the reconfiguration manufacturing technique of the present study decreased lead time by 21.62%.