• Journal of Energy Engineering
• /
• v.25 no.1
• /
• pp.43-47
• /
• 2016

KHNP CRI has developed APR+ nuclear power plant since 2007, which is GEN III+ model with 1500 MWe capacity. To develop safer nuclear power plant than APR1400, we investigated advanced design features of ALWR being constructed in Korea and being developed/constructed in foreign countries. We applied the advanced design features and lessons learned from Fukushima accident to develop APR+ standard design suitable for both domestic construction and overseas construction business. One economic assessments have performed during safety design improvement phase(2013.1 ~ 2015.12) of APR+. The result of the economic analysis for APR+ safety inhancement design showed that APR+ N-th plant is about 39.2% more economical than coal-fired 1,000MW power plant. Also APR+ plant is more cost advantage over foreign advanced nation ALWRs.

• Journal of Microbiology and Biotechnology
• /
• v.32 no.6
• /
• pp.800-807
• /
• 2022

Four aprE genes encoding alkaline serine proteases from B. subtilis strains were used as template genes for family gene shuffling. Shuffled genes obtained by DNase I digestion followed by consecutive primerless and regular PCR reactions were ligated with pHY300PLK, an E. coli-Bacillus shuttle vector. The ligation mixture was introduced into B. subtilis WB600 and one transformant (FSM4) showed higher fibrinolytic activity. DNA sequencing confirmed that the shuffled gene (aprEFSM4) consisted of DNA mostly originated from either aprEJS2 or aprE176 in addition to some DNA from either aprE3-5 or aprESJ4. Mature AprEFSM4 (275 amino acids) was different from mature AprEJS2 in 4 amino acids and mature AprE176 in 2 amino acids. aprEFSM4 was overexpressed in E. coli BL21 (DE3) by using pET26b(+) and recombinant AprEFSM4 was purified. The optimal temperature and pH of AprEFSM4 were similar to those of parental enzymes. However, AprEFM4 showed better thermostability and fibrinogen hydrolytic activity than the parental enzymes. The results indicated that DNA shuffling could be used to improve fibrinolytic enzymes from Bacillus sp. for industrial applications.

• Journal of Energy Engineering
• /
• v.23 no.4
• /
• pp.236-239
• /
• 2014

KHNP CRI has been developing APR+ nuclear power plant since 2007, which is GEN III+ model with 1500 MWe capacity. To develop safer and more economical nuclear power plant than APR1400, we investigated advanced design features of ALWR(advanced light water reactor) being constructed in Korea and being developed/constructed in foreign countries. We applied the advanced design features and lessons learned from Fukushima accident to develop APR+ standard design suitable for both domestic construction and overseas construction business. Three economic assessments have performed during standard design phase of APR+. The result of the 3th(final) economic analysis for APR+ standard design showed that APR+ N-th plant was about 23% more economical than coal-fired 1,000MW power plant.

• Journal of Microbiology and Biotechnology
• /
• v.24 no.7
• /
• pp.969-978
• /
• 2014

The aprE2 gene with its prosequence from Bacillus subtilis CH3-5 was overexpressed in Escherichia coli BL21(DE3) by using plasmid pET26b(+). After IPTG induction, active and mature AprE2 was produced when cells were grown at $20^{\circ}C$, whereas inactive and insoluble enzyme was produced in a large amount when cells were grown at $37^{\circ}C$. The insoluble fraction was resuspended with 6 M guanidine-HCl and dialyzed against 2 M Tris-HCl (pH 7.0) or 0.5 M sodium acetate (pH 7.0) buffer. Then active AprE2 was regenerated and purified by a Ni-NTA column. Purified AprE2 from the soluble fraction had a specific activity of $1,069.4{\pm}42.4U/mg$ protein, higher than that from the renatured insoluble fraction. However, more active AprE2 was obtained by renaturation of the insoluble fraction. AprE2 was most stable at pH 7 and $40^{\circ}C$, respectively. The fibrinolytic activity of AprE2 was inhibited by PMSF, but not by EDTA and metal ions. AprE2 degraded $A{\alpha}$ and $B{\beta}$ chains of fibrinogen quickly, but not the ${\gamma}$-chain. AprE2 exhibited the highest specificity for N-succinyl-Ala-Ala-Pro-Phe-pNA. The $K_m$ and $k_{cat}/K_m$ of AprE2 was 0.56 mM and $3.10{\times}10^4S^{-1}M^{-1}$, respectively.

• Journal of the Korean Society of Safety
• /
• v.31 no.6
• /
• pp.129-134
• /
• 2016

Standard design of APR+(advanced power reactor plus) was certified at 2014 by Korea regulatory body. Based on the experience gained from OPR1000 and APR1400, the APR1400 was being developed as a 1,500MWe class reactor using Korean technologies for design code, reactor coolant pump, and man-machine interface system. APR+ has been basically designed to have the seismic design basis of safe shutdown earthquake (SSE) 0.3g, a 4-train safety concept based on N+2 design philosophy, and a passive auxiliary feedwater system (PAFS). Also, safety issues on the Fukushima-type accidents have been extensively reviewed and applied to enhance APR+ safety. APR+ provides higher reliability and safety against tsunami and earthquake. The purpose of this paper is to implement probabilistic safety assessment considering these design features and to analyze sensitivity of core damage frequency for large loss of coolant accident of APR+.

• Nuclear industry
• /
• v.30 no.3
• /
• pp.72-78
• /
• 2010

KEPCO는 APR1000 원전을 개발 중에 있다. APR1000은 2루프 1000MWe급의 가압경수로로, 국내에 운영중이고 건설중인 검증된 OPR1000 설계를 기반으로 하고 있다. APR1000은 원전 수요자의 요구에 응하기 위해 안전성, 신뢰성 및 경제성을 설계에 고려하여 개발 중에 있다. APR1000의 대표적인 설계 특성으로는 60년 수명, 0.3g 내진 설계, MMICs, 저온 덮개 원자로(Cold Head Reactor), 안전 주입 탱크 내의 피동형 유량 조절 장치 등이 있다. 본고에서는 APR1000의 설계 요건과 안전 관련 설게 특징을 소개하고자 한다.

• Journal of Life Science
• /
• v.23 no.1
• /
• pp.15-23
• /
• 2013

AprE51 from Bacillus amyloliquefaciens CH51 is a 27 kDa subtilisin-like protease with fibrinolytic activity. AprE51-6 showing increased catalytic activity was produced previously. To enhance the thermostability of AprE51-6, 2 residues, Gly-166 and Asn-218 based on B. subtilis subtilisin E were mutated by site-directed mutagenesis. The results of the mutational analysis showed that substitution of arginine for Gly-166 (AprE51-7) increased the fibrinolytic activity 1.8-fold. An N218S mutant (AprE51-8) also increased the fibrinolytic activity up to 4.5-fold in a fibrin plate assay. Purified AprE51-7 and AprE51-8 mutants had a 1.9- and a 2.5-fold higher $k_{cat}$, respectively, and a 2.1-1.9-fold lower $K_m$, respectively. This resulted in a 3.8- and a 4.7-fold increase in catalytic efficiency ($k_{cat}/K_m$), respectively, relative to that of wild-type AprE51. AprE51-8 had a broader pH range than AprE51-6 and nattokinase, especially at an alkaline pH value. In addition, AprE51-8 showed higher thermostability than AprE51-6 at $60^{\circ}C$. The half-lives of AprE51-7 and AprE51-8 at $50^{\circ}C$ were 21.5 and 27.3 min, respectively, which are 2.0 and 2.6 times longer, respectively, than that of the wild-type AprE51.

• Journal of Acupuncture Research
• /
• v.23 no.3
• /
• pp.191-206
• /
• 2006

Objective & Methods : The purpose of this study is to observe the effects of Angelicae Pubescentis Radix herbal-acupuncture solution(APR-HAS) at Joksamni(ST36) on collagen IT induced arthritis in DBA/1J mice. The author performed several experimental items to analyze several cytokines and immune cells related with RA. Results : 1. In the APR-HA group, the incidence of arthritis and arthritis index were significantly decreased. 2. In APR-HA group, the levels of IL-6, $INF-{\gamma}$, $TNF-{\alpha}$, IgG, IgM, $IL-{\beta}$ and Anti-collagen II in serum of the CIA mouse were significantly decreased. 3. In APR-HA group, the level of $IFN-{\gamma}$, IL-4 in the CIA mouse spleen cell culture were significantly decreased. 4. In histology, the cartilage destruction and synovial cell proliferation were decreased in the APR-HA group, and the collagen fiber expressions in the APR-HA group were similar with that of the Normal group. 5. In the APR-HA group, CD3e+/CD19+ and CD4+/CD8+ were similarly maintained as Normal group in the CIA mouse lymph nodes, 6. In the APR-HA group, CD3e+/CD69+ was significantly decreased in the CIA mouse joint. 7. In the APR-HA group, CD11a+/CD19+ and CD11b+/Gr-l+ were significantly decreased in the CIA mouse lymph nodes 8. In the APR-HA group, CD4+/CD25+ was decreased in the CIA mouse spleen cell. 9. In the APR-HA group, CD4+/CD25+ was similarly maintained as Normal group in the CIA mouse lymph nodes.

• Nuclear Engineering and Technology
• /
• v.41 no.8
• /
• pp.995-1004
• /
• 2009

The Advanced Power Reactor 1400 (APR1400) is an evolutionary advanced light water reactor (ALWR) based on the Optimized Power Reactor 1000 (OPR1000), which is in operation in Korea. The APR1400 incorporates a variety of engineering improvements and operational experience to enhance safety, economics, and reliability. The advanced design features and improvements of the APR1400 design include a pilot operated safety relief valve (POSRV), a four-train safety injection system with direct vessel injection (DVI), a fluidic device (FD) in the safety injection tank, an in-containment refueling water storage tank (IRWST), an external reactor vessel cooling system, and an integrated head assembly (IHA). Development of the APR1400 started in 1992 and continued for ten years. The APR1400 design received design certification from the Korean nuclear regulatory body in May of2002. Currently, two construction projects for the APR1400 are in progress in Korea.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2014.10a
• /
• pp.399-401
• /
• 2014

The comprehensive vibration assessment program(CVAP) of APR+ nuclear power plant(NPP) is classified as non-prototype, category II with Palo Verde NPP as valid prototype. In this paper, CVAP for first plant of APR+ NPP is proposed. The Control Element Assembly(CEA) shroud of APR+ NPP is different from that of Palo Verde NPP. And the Core Support Barrel(CSB) outer diameter and the flow rate of normal operation of APR+ NPP are larger than those of Palo Verde NPP. Vibration and stress analysis program should be conducted to establish test acceptance criteria. Limited vibration measurement program should be implemented to establish the margin of safety, demonstrate the satisfaction of test acceptance criteria and confirm the similar vibratory response between the APR+ and Palo Verde NPP. Because of the change of normal operation condition, the nominal differences between APR+ and Palo Verde NPP in the structural and hydraulic analysis are studied to determine the measurement locations.