Boundary condition coupling methods and its application to BOP-integrated transient simulation of SMART

Jongin Yang,Hong Hyun Son,Yong Jae Lee,Doyoung Shin,Taejin Kim,Seong Soo Choi Korean Nuclear Society 2023 Nuclear Engineering and Technology Vol.55 No.6

The load-following operation of small modular reactors (SMRs) requires accurate prediction of transient behaviors that can occur in the balance of plants (BOP) and the nuclear steam supply system (NSSS). However, 1-D thermal-hydraulics analysis codes developed for safety and performance analysis have conventionally excluded the BOP from the simulation by assuming ideal boundary conditions for the main steam and feed water (MS/FW) systems, i.e., an open loop. In this study, we introduced a lumped model of BOP fluid system and coupled it with NSSS without any ideal boundary conditions, i.e., in a closed loop. Various methods for coupling boundary conditions at MS/FW were tested to validate their combination in terms of minimizing numerical instability, which mainly arises from the coupled boundaries. The method exhibiting the best performance was selected and applied to a transient simulation of an integrated NSSS and BOP system of a SMART. For a transient event with core power change of 100-20-100%, the simulation exhibited numerical stability throughout the system without any significant perturbation of thermal-hydraulic parameters. Thus, the introduced boundary-condition coupling method and BOP fluid system model can expectedly be employed for the transient simulation and performance analysis of SMRs requiring daily load-following operations.

순환 유동상 연소로 설계 인자 및 하부 연소율에 따른 설계 영향 평가

양종인(Jongin Yang),김태현(Taehyun Kim),최상민(Sangmin Choi) 한국연소학회 2012 KOSCOSYMPOSIUM논문집 Vol.- No.44

RDF 전용 CFB 보일러의 설계 인자 도출 및 설계 접근 방법

양종인(Jongin Yang),김태현(Taehyun Kim),최상민(Sangmin Choi) 한국연소학회 2011 KOSCOSYMPOSIUM논문집 Vol.- No.43

Circulating fludized bed boiler which can use a variety of fuel type turns out to be a very effective system. If this plant use RDF fuel, we can get a chance to save money and use heat resource. This study is aimed to derive design parameter of Circulating fludized bed boiler using RDF fuel through existing plant and represent CFB boiler design process using reverse engineering concept. However, more investigation about fuel combustion chracteristic should be performed for design of Boiler considering RDF fuel characteristic.

340MWe급 순환 유동상 보일러의 단순 성능 예측 모형

양종인(Jongin Yang),최상민(Sangmin Choi) 한국연소학회 2012 KOSCOSYMPOSIUM논문집 Vol.- No.45

Circulating fluided bed(CFB) furnace which can use a variety of low-grade fuels because of high heat capacity and good mixing characteristic in its furnace have turned out to be effective system. There is no many research to predict performance considering total boiler system with water-steam side. Most of performance prediction model have focused on hydrodynamics or chemical mechanism in furnace. so, This study is aimed to develop performance prediction model which consider water-steam side.

초임계 오일 연소 보일러의 동특성 예측 연구

양종인(Jongin Yang),김정래(Jungrae Kim) 한국연소학회 2014 KOSCOSYMPOSIUM논문집 Vol.2014 No.11

RDF 및 유ㆍ무연탄을 사용하는 순환 유동상 보일러의 열 및 물질 정산

양종인(Jongin Yang),김태현(Taehyun Kim),최상민(Sangmin Choi),김재성(Jae-Sung Kim),이종민(Jong-Min Lee),김동원(Dong-Won Kim) 한국연소학회 2011 KOSCOSYMPOSIUM논문집 Vol.- No.42

Circulating fluidized bed boiler which can use a variety of fuel type turns out to be a very effective combustion system. The 200㎿e class thermal power plant CFB boiler in Korea was installed in 1998, 1999 respectively, and it becomes the largest boiler to fire anthracite with butuminous Coal in Korea. Co-Combustion with refuse derived fuel(RDF) also has been considered as a promising fuel in a circulating fludized bed boiler. In this study, heat and mass balance is calculated for the CFB boiler using korean anthracite, bituminous and refuse derived fuel. By calculating 0-dimensional heat and mass balance, effects of Co-Combustion are discussed about required fuel flow rate, total air flow rate sorbent rate and flue gas temperature.

Association between irregular working hours and work-related musculoskeletal pain: results from the 6th Korean Working Conditions Survey

Yang Munyoung,Myong Jun-Pyo,Lee Jongin,Park Min Young,Kang Mo-Yeol 대한직업환경의학회 2023 대한직업환경의학회지 Vol.35 No.1

Background: Recently, irregular working hours have become controversial issues in Korea. The health impact of irregular working hours on the work-related musculoskeletal pain (MSP) is scarcely researched before. We sought to investigate the association between irregular working hours and work-related MSP among South Korean workers. Methods: This study used data from the sixth Korean Working Conditions Survey in 2020. The prevalence of work-related MSP was analyzed using the χ2 test. A multiple logistic regression analysis was conducted to assess the association between irregular working hours and work-related MSP. We conducted stratified analysis by gender, weekly working hours, and workers’ control over their working hours. We calculated the adjusted odds ratios (ORs) of work-related MSP for irregular working hours combined with weekly working hours. Results: The OR for work-related MSP was significantly higher in the population with irregular working hours than in the population with regular working hours (OR: 1.43, 95% confidence interval [CI]: 1.29–1.58). Irregular and long (> 52 hours/week) working hours have the highest risk of work-related MSP in both genders (in men, OR: 3.48 [95% CI: 2.53–4.78]; in women, OR: 2.41 [95% CI: 1.46–4.00]). Conclusions: Irregular working hours were associated with work-related MSP in Korea. The association was magnified with long working hours. Reform of the Korean Labor Standards Act leading to increase irregular working hours may induce adverse health outcome.

Specific DNA Markers Selection Using Miniature Inverted-Repeat Transposable Element (MITE)Families in Brassica Juncea

Kiwoung Yang,Go-eun Yi,Arif Hasan Khan Robin,Jongin Park,Ill-Sup Nou 한국원예학회 2015 한국원예학회 학술발표요지 Vol.2015 No.5

갓 (Brassica juncea) 품종구분을 위한 ITS 영역 및 MITE Family 정보를 이용한 분자표지 개발

양기웅(Kiwoung Yang),이고은(Go-eun Yi),아리프 하산 칸 로빈(Arif Hasan Khan Robin),정남희(Namhee Jeong),이용혁(Yong-Hyuk Lee),박종인(Jongin Park),김회택(Hoyteak Kim),정미영(Mi-Young Chung),노일섭(Ill-Sup Nou) 한국원예학회 2016 원예과학기술지 Vol.34 No.2

갓(Brassica juncea; 2n = 4x = 36, AABB genome, 1,068Mb)은 U’s triangle의 배추와 흑겨자 사이의 복이배체 작물로 구분한다. 본 연구는 갓 15 품종의 ribosomal DNA ITS 영역과 MITE를 이용하여 갓의 유연관계 및 품종구분 분자표지를 확인하였다. Ribosomal DNA ITS 영역은 종 및 품종의 유연관계를 알아보는 연구로 많이 사용되고 있어서, 이를 이용하여 갓 15 품종의 유연관계를 알아보았다. 또한, MITE는 매우 많은 copy 수를 가지고 있고, 유전적으로 안정적이기 때문에 유전체 및 진화연구에 매우 적합한 재료이다. MITE를 이용한 갓의 품종구분 분자표지를 확인하기 위해 MITE super-families 중 Stowaway(BraSto) 관련 70점, Tourist(BraTo) 관련 79점, hAT(BrahAT) 관련 6점, Mutator(BraMu) 관련 5점으로 품종구분 표지를 알아보았다. 총 160점의 분자표지 중 32점이 갓 15 품종에서 뚜렷한 다형성을 보였다. 특히, 흑갓은 표현형뿐만 아니라 유전자형도 매우 다르게 나타났다. 또한 8점의 MITE 분자표지를 활용하여 47점의 유전자원에서 다형성 및 품종구분 표지로의 활용 가능성을 확인하였다. 이러한 다형성 표지들은 갓의 품종구분 및 품종 보호에 매우 유용하게 사용할 수 있을 것이라 기대한다. Brassica juncea (2n = 4x = 36, AABB genome, 1,068 Mb) is a U’s triangle species and an amphidiploid derivative of B. rapa and B. nigra. Fifteen varieties were used to study the ITS (internal transcribed spacer) regions of ribosomal DNA and MITEs (miniature inverted-repeat transposable elements) with a view of developing specific molecular markers. ITSs and MITEs are an excellent resource for developing DNA markers for genomics and evolutionary studies because most of them are stably inherited and present in high copy numbers. The ITS (ITS1 and ITS2) sequence was compared with the consensus sequence of B. rapa and B. nigra. Variation in ITS1 created two separate groups among 15 varieties, with 10 varieties in one group and 5 in the other. Phylogenetic analysis revealed two major clusters for those 10 and 5 varieties. Among the 160 different MITE primers used to evaluate the selected 15 varieties of B. juncea, 70 were related to the Stowaway, 79 to the Tourist, 6 to the hAT, and 5 to the Mutator super-families of MITEs. Of 160 markers examined, 32 were found to be polymorphic when fifteen different varieties of B. juncea were evaluated. The variety ‘Blackgat’ was different from the other mustard varieties with respect to both phenotype and genotype. The diversity of 47 additional accessions could be verified using eight selected molecular markers derived from MITE family sequences. The polymorphic markers identified in this study can be used for varietal classification, variety protection, and other breeding purposes.

상사의 서번트 리더십이 조직시민행동에 미치는 영향

양지혜(Jihye Yang),김종인(Jongin Kim) 한국전략경영학회 2017 전략경영연구 Vol.20 No.1

본 연구는 물질만능주의가 팽배한 현대사회에서 자신의 일이 가지는 의미와 가치를 인식하는 것이 서번트 리더십, 조직시민행동과 어떤 관계를 갖는지를 실증하고자 하였다. 서울 및 수도권 소재 기업의 사무직 종사자 418명을 대상으로 설문조사를 실시하여 데이터를 수집한 후, SPSS 23.0과 AMOS 23.0 통계프로그램을 사용하여 가설을 검증한 결과, 상사의 서번트 리더십을 높게 지각하는 직원들이 본인의 일의 의미와 가치를 더욱 높게 인식하는 것으로 나타났으며 일의 의미는 조직시민행동에도 유의한 정(+)의 영향을 미치는 것으로 나타났다. 또 서번트 리더십이 조직시민행동에 미치는 직접적인 설명력보다 일의 의미가 투입된 경우의 설명력이 더 높은 것으로 확인되어 일의 의미는 서번트 리더십과 조직시민행동 간의 관계를 매개하는 것으로 분석되었다. 일의 의미라는 개념을 변수로 한 연구가 미흡한 상황에서 서번트 리더십, 조직시민행동 간의 관계를 확인하였으며 이를 통해 서번트 리더십과 일의 의미가 조직에 가져오는 긍정적인 영향력을 밝혀내었다. The purpose of this study is to find out the effect of meaning of work in the relation with servant leadership and organizational citizenship behavior in the age of materialism. Survey method was used to prove the study hypothesis using data collected from employees(n=418) working for companies in Seoul and some other capital area, and SPSS Statistics 23.0, AMOS 23.0 programs are used in analysis. The results are as follows; firstly, employees who perceived their leaders’ servant leadership higher thought their jobs had more meaning and value. Secondly, the meaning of work had a positive effect on employees’ organizational citizenship behavior. Thirdly, meaning of work had a mediating effect between servant leadership and organizational citizenship behavior as the direct effect of servant leadership on organizational citizenship behavior was smaller than the indirect effect when meaning of work was put in the middle. This study has some implications; firstly, meaning of work has not been considered in many studies yet. Most of the studies trying to find out the relationship between servant leadership and organizational citizenship considered trust and empowerment as mediating variables. Throughout this study, employees’ having the meaning and value of their jobs were proved that it had positive effects on organizational citizenship behavior. Secondly, as servant leadership had positive effects on both meaning of work and organizational citizenship behavior, the result could guide the direction of leadership training in domestic companies to directly and indirectly improve organizational performances.