발표 22 : Fe-C-Si-B 계 비정질 합금의 비정질 형성능에 미치는 첨가원소의 영향

임현규,이승훈,김원태,김도향 대한금속재료학회 ( 구 대한금속학회 ) 2000 대한금속재료학회 학술대회 개요집 Vol.2000 No.0

일측 흑질체 및 복측피개 파괴 백서에서 도파민 D1효현제 및 도파민 D2 효현제가 회전운동에 미치는 영향

임현규,유상은,황익근,은홍배 대한신경정신의학회 1995 신경정신의학 Vol.34 No.5

To investigate the role of dopamine D1 and D2 recepters on circling behavior, effects of SKF 38393 and LY 171555 were examined in rats with 6-OHDA-lesioned substantia nigra or in rats with 6-OHDA-lesioned ventral tegmentum. 1) In the rats with 6-OHDA-lesioned substantia nigra, SKF 38393,dopamine D1 agonist, elicited contralatral rotation in a fraction o f the lesioned animals(60%), while LY 171555, dopamine D 2 agonist, elicited contralatral rotation in the entire animals. 2) In the rats with 6-OHDA-lesioned ventral tegmentum, SKF 38393 elicited contralatral rotation in a fraction of the lesioned animals, while LY 171555 elicited contralatral rotation in the entire animals. 3) In the rats which SKF 38393 induced contralatral rotation, circling ofFects of dopamine D1 agonist and D2 agonist in rats with 6-OHDA-lesioned substantia nigra were not different from those in rats with 6-OHDA-lesioned ventral tegmentum. 4) In the rats which SKF 38393 failed to induce contralateral rotation, the influence of dopamine D i agonist and dopamine D2 agonist on the circling behavior in the rats with 6-OHDAlesioned ventral tegmentum was signiricantly lower than that in the rats with 6-OHDA-lesioned substantia nigra. 5) In the rats which SKF 38393 failed to induce contralatral rotation, there was not priming effect in rats with 6-OHDA-lesioned ventral tegmentum but in rats with 6-OHDA-lesioned substantia nigra. From the above results, it is concluded that both dopamine D1 agonist and D2 agonist can elicit contralateral ratation in rats with 6-OHDA-lesioned ventral tegmentum as well as in rats with 6-OHDA-lesioned substantia nigra and that anatomical location o f lesioned area is im portant for development of priming effect

조선소 시뮬레이션의 물류 분석을 위한 지리정보 구조 정의

임현규,이용길,이필립,우종훈 한국경영과학회 2016 한국경영과학회 학술대회논문집 Vol.2016 No.4

조선소의 생산 프로세스는 일반 제조업에 비해 복합적인 생산방식을 가지고 있기 때문에 전통적인 시뮬레이션 방법으로는 표현하기에 어려운 점이 존재한다. 이를 해결하기 위한 시뮬레이션 방법론에 대한 연구가 지속적으로 진행되고 있는데, 그 중 하나가 공정중심(Process Centric)의 DES 시뮬레이션 방법론이다. 공정중심 DES 시뮬레이션의 경우 복잡한 액티비티 네트워크로 구성되는 선박 건조 공정을 모델링하고 시뮬레이션 하는데 있어 설비중심의 시뮬레이션과 비교하여 모델링의 난이도와 시뮬레이션 수행시간에 있어 장점을 지니고 있다. 하지만 공정중심 방법론의 단점은 액티비티 네트워크 중심으로 시뮬레이션을 수행하기 때문에 설비들 간의 물류(Logistics)를 분석하는데 한계가 있다. 즉, 물류 분석을 위해서는 제품이 설비 간에 운송되는 시간과 운송설비, 이동경로와 관련된 결과가 도출이 되어야 하는데 액티비티 네트워크로 모델이 구성이 되는 공정중심 방법론에서는 그 자체만으로는 물류 거동에 대한 고려가 불가능하다. 본 연구에서는 공정중심 DES 시뮬레이션 환경에서 물류분석이 가능하게 하기 위한 방법론을 제안하고, 물류분석이 가능하게 하기 위한 지리정보 구조를 정의하였다. 본 논문에서 제안하는 지리정보 구조는 공정중심 DES 시뮬레이션 플랫폼에 탑재가 되어 공정과 물류모듈간의 정보교환을 위한 인터페이스 역할을 하게 된다.

연구를 시작한지 어느덧 10년, 그리고 앞으로의 계획

임현규 한국생물공학회 2021 BT NEWS Vol.28 No.2

특집마당 : 마그네슘 합금 개발 동향

임현규,양원석,오건영,정영길 대한금속재료학회(구 대한금속학회) 2014 재료마당 Vol.27 No.6

Efficient n-butanol production from red seaweed hydrolysate by engineered Escherichia coli

임현규,임재형,정규열 한국공업화학회 2014 한국공업화학회 연구논문 초록집 Vol.2014 No.1

Galactose and glucose can be achieved by dilute acid or enzymatic treatment of red seaweed, many bio-chemicals can be produced from these sugars through fermentation process. However, the challenging problem is that galactose is not favored by many industrial microorganisms. Slow utilization rate and carbon catabolite repression limits carbon flux and results in low productivity and titer. In this research, we introduced two synthetic modules to utilize sugars from hydrolysate of red seaweed (Gelidium amansii) and to produce n-butanol, one of advanced fuel. The modules with metabolic enzymes under synthetic promoters, rationally designed 5’UTRs (5’untranslated region), and terminators were assembled, and these modules were optimized by finding maximum productivity with various expression of specific gene. With this approach, the engineered strain showed significantly enhanced sugar utilization and n-butanol production from both red seaweed mimetic media and real hydrolysate.

n-Butanol prouction from galactose-glucose mixtures via modular design of metabolic network

임현규,임재형,정규열 한국공업화학회 2018 한국공업화학회 연구논문 초록집 Vol.2018 No.0

Refactoring microorganisms for efficient production of advanced biofuel from a mixture of sugars in the cheap feedstock is essential in biorefinery. However, its production is highly challenging due to the slower utilization of biomass-driven sugars, difficulties in amplification of biosynthetic pathways for heterologous metabolite, and redox imbalance. In this study, we engineered Escherichia coli to accomplish high production of n-butanol from galactose-glucose mixtures. Three modular pathways were assembled for galactose utilization, n-butanol production, and redox re-balancing to robustly produce n-butanol. The engineered strain showed high n-butanol production (6.2 g/L after 48-h fermentation) in galactose-supplemented medium. Moreover, fermentation with mixtures of galactose and glucose at various ratios confirmed that our engineered strain was able to robustly produce n-butanol regardless of sugar composition with simultaneous utilization of galactose and glucose.

Precise Auxotrophic Control for Stable and Tunable Maintenance of Plasmids for Antibiotic-free Cultivation

임현규,강채원,양진아,서상우,정규열 한국공업화학회 2018 한국공업화학회 연구논문 초록집 Vol.2018 No.0

Although plasmid-based expression systems have advantages in multi-copy expression of genes, heterogeneity of plasmid copy number (PCN) in individual cells is inevitable even with the addition of antibiotics. Here, we developed a synthetic auxotrophic system for stable and tunable maintenance of the PCN in Escherichia coli without addition of antibiotics. This auxotroph expresses infA, one of the essential genes encoding a translation initiation factor, on a plasmid instead of on the chromosome. With this system, the gene expression was stably maintained for 40 generations with minimized cell-to-cell variation under antibiotic-free conditions. Moreover, varying the expression level of infA enabled us to rationally tune the PCN by more than 5.6-fold. This antibiotic-free PCN control system significantly improved the production of itaconic acid (1.7-fold) and lycopene (2-fold) compared to the conventional system based on antibiotics.

Effects of Rolling Condition on the Tensile Properties of Mg-MM-Sn-Al-Zn Alloy

임현규,김도형,이주연,경준석,김원태,김도향 대한금속·재료학회 2009 METALS AND MATERIALS International Vol.15 No.2

The microstructures and mechanical properties of Mg-2MM-2Sn-1Al-1Zn (ETAZ2211) sheets fabricated under different conditions have been investigated. Two hot-rolling routes following extrusion have been carried out at 300 °C or 400 °C. One method is to roll the extruded strips parallel to the extrusion direction (ED); the other is to roll the extruded strips perpendicular to the extrusion direction (TD). The strength and the elongationto- fracture of specimens prepared by a combination of extrusion and rolling processes are increased dramatically when compared those of the simply rolled specimens. Especially, the TD alloy sheet rolled at 300 °C exhibits the best combination of strength and ductility, i.e. yield strength of 178.5 MPa, ultimate tensile strength of 239.1 MPa, uniform elongation of 24.4 % and elongation-to-fracture of 37.9 %. Observation of texture reveals that the intensity of (0002) texture is lower for the TD alloy sheets than that for the ED alloy sheets, indicating that the texture intensity is reduced by change of the rolling direction. The microstructures and mechanical properties of Mg-2MM-2Sn-1Al-1Zn (ETAZ2211) sheets fabricated under different conditions have been investigated. Two hot-rolling routes following extrusion have been carried out at 300 °C or 400 °C. One method is to roll the extruded strips parallel to the extrusion direction (ED); the other is to roll the extruded strips perpendicular to the extrusion direction (TD). The strength and the elongationto- fracture of specimens prepared by a combination of extrusion and rolling processes are increased dramatically when compared those of the simply rolled specimens. Especially, the TD alloy sheet rolled at 300 °C exhibits the best combination of strength and ductility, i.e. yield strength of 178.5 MPa, ultimate tensile strength of 239.1 MPa, uniform elongation of 24.4 % and elongation-to-fracture of 37.9 %. Observation of texture reveals that the intensity of (0002) texture is lower for the TD alloy sheets than that for the ED alloy sheets, indicating that the texture intensity is reduced by change of the rolling direction.

회전익기 요 스웨지드 로드 분할에 따른 비행 안전성에 대한 해석적 접근

임현규,최재형,김대한,장민욱,윤재휘,양필주,Lim, Hyun-Gyu,Choi, Jae-hyung,Kim, Dae-Han,Jang, Min-Wook,Yoon, Jae-Huy,Yang, Pil-Joo 한국항공운항학회 2017 한국항공운항학회지 Vol.25 No.3

As for A rotary wing aircraft, the configuration change about split yaw swaged rod was executed to improve hit treat capability for dealing with a long rod. The purpose of this study was to analyze if or not the quality of the split yaw swaged rod was obtained, and so the flight safety was ensured or not. Buckling analysis, Coupling Thread Strength Analysis, Thermal Stress analysis and Rod Natural Frequency Analysis were executed for structural analysis. The results of the analysis were presented that the split rod had the sufficient margin of safety and so there were no anomalies in the limit load and no failures in the ultimate load. And there were no resonances in result of natural frequency analysis. In conclusion, this study showed that the split yaw swaged rod had structural safety, so flight safety of rotary wing aircraft was secured and there was no problem in aircraft operation. It is certain that the technology of splitting the yaw swage rod will contribute to the operational Safety of the rotary wing aircraft in the future.