Development of Bovine Nuclear Transfer Embryos Using Life-span Extended Donor Cells Transfected with Foreign Gene

Hwang, Seongsoo,Choi, Eun Joo,You, Seungkwon,Choi, Yun-Jaie,Min, Kwan-Sik,Yoon, Jong-Taek Asian Australasian Association of Animal Productio 2006 Animal Bioscience Vol.19 No.11

This study was performed to determine the developmental potentials of nuclear transfer (NT) embryos using life-span extended cells transfected with a foreign gene as donor cells. A life-span extended bovine embryonic fibroblast cell line was transfected with an expression vector in which the human type II collagen (BOMAR) and ear fibroblasts were used as a donor cell. Cytogenetic analysis was performed to analyze the chromosomal abnormality of donor cells. The fusion rate of 1.8 kV/cm for $15{\mu}sec$ given twice was significantly higher than that of other groups (p<0.05) and the embryos lysed were significantly higher after 1.8 kV/cm for $20{\mu}sec$ given once compared to other groups (p<0.01). The blastocyst development in the ear cell group was statistically significant compared to both BOMAR groups (p<0.01). Both BOMAR groups cultured more than 40 passages (>40 passages) had a lower number of chromosomes; however, fresh granulosa cell (GC) and BOMAR groups cultured less than 20 passages had normal chromosome numbers. Both >40 passages BOMAR groups had numerous obscure debris in metaphase spreads. The transfected foreign gene was expressed in all BOMAR groups, but not in the GC group. Based on these results, the lower developmental potential of NT embryos using life-span extended donor cells transfected with a foreign gene might be a cause of chromosomal abnormality in donor cells.

COMBUSTION SYSTEM DESIGN OF A GENSET DIESEL ENGINE BY USING DFSS METHODOLOGY

Taejoong Wang,Seungkwon Hwang 한국자동차공학회 2019 International journal of automotive technology Vol.20 No.3

In this study, an optimum design for the combustion system of a genset diesel engine was conducted by using Design for Six Sigma (DFSS) methodology. As a result of this study, the best combination of design parameters to minimize the fuel consumption of the genset diesel engine was selected while meeting the requirements of NOx emission and peak firing pressure (PFP) limit. Compared to the initial design, the final design proposal has achieved 2.5 % and 1.6 % improvement in brake specific fuel consumption (BSFC) at switchable operating conditions, i.e., both 1500 and 1800 rpm. On the basis of this DFSS work, the design robustness was also enhanced. Hence, it is expected that the final design proposal would reduce the variability in fuel economy that could be caused by harsh environment and system aging. In this study, engine cycle simulation technique was employed to assess the effects of various design parameters on the performances of the genset diesel engine. The current optimum design work has considered four control factors such as turbocharger size, air temperature at charge air cooler (CAC) outlet, compression ratio, and fuel injection duration. Here, an L9 orthogonal array was used to efficiently choose the best design proposal among 81 design combinations (i.e., four independent control factors which individually have three different levels).

조현병 대상자를 위한 그룹 행동활성화 프로그램의 효과

송승권 ( Song Seungkwon ),황정하 ( Hwang Jeongha ) 한국보건사회연구원 2021 保健社會硏究 Vol.41 No.1

조현병 환자를 대상으로 하는 근거기반 정신사회적 중재프로그램에 대한 요구는 증가하고 있다. 본 연구의 목적은 조현병 대상자들에게 그룹 행동활성화(GBA) 프로그램이 정신병적 증상, 우울감, 주관적 안녕감에 효과적인지, 그리고 지역사회 중재프로그램으로 활용이 가능한지 검증하는 데 있다. 이를 위해 G정신건강복지센터 등록 조현병회원 중 연구 참여를 희망하는 회원 35명을 모집하였다. 실험집단 18명, 통제집단 17명의 참여자를 프로그램 참여 욕구에 따라 할당하였고, 10회기의 그룹 행동활성화 프로그램 진행 전·후 사전-사후검사 결과를 비교 분석하였다. 연구결과 그룹 행동활성화 프로그램은 실험집단의 정신병적 증상과 그 하위척도, 우울감, 주관적 안녕감에서 유의미한 호전을 보였다. 본 연구가 무선할당을 하지 못한 한계점이 있지만 그룹 행동활성화 프로그램이 조현병 대상자의 정신병적 증상과 음성증상을 효과적으로 호전시킬 것이라는 가설을 입증하였다. 본 연구결과를 토대로 지역사회에서 근거기반의 정신사회적 중재로서 그룹 행동활성화 프로그램이 활용 가능한지를 논의하였다. The need has increased for evidence-based psycho-social intervention for community-dwelling patients with schizophrenia. This study was conducted to confirm whether the group behavioral activation program (GBAP) is effective to psychotic symptoms, depression, subjective well-being. A total of 35 enrolled schizophrenic patients from a community mental health center in G-province participated in the study. The experimental group was divided into A and B groups for the effect of group treatment, and PANSS, CES-D, SWN-K were measured by pre-post tests. A total of 10 sessions were conducted weekly for 10 weeks, and it was conducted in group-focused program. A covariance analysis (ANCOVA) was performed to verify the effectiveness of the program in detail with the pre-score as covariates, and some paired t-tests were performed to compare pre-post scores. The results showed that the GBAP showed significant improvement in the psychotic symptoms and sub-scales such as positive symptoms, negative symptoms, general psychopathology. Based on these results, this study introduced the GBAP as an evidence-based psycho-social intervention program that can be effectively utilized in the community.

Design of combustion bowl geometry to meet final Tier 4 of 11 L non-road heavy-duty diesel engine with multi-dimensional combustion simulation

Sangyul Lee,Jongyoon Lee,Seungkwon Hwang,Taejoong Wang,Youngbok Lee 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.9

To comply with the new non-road emission standards, final Tier 4, two big strategies have been applied to the 11 L heavy-duty diesel engine. The first strategy is to apply Exhaust gas recirculation and selectivity catalytic reduction system to meet the NOx limitation. The other one is to apply low swirl ratio (for higher volumetric efficiency) and multi-hole nozzle, a high pressure direct injection, and an optimized combustion system in order to reduce PM emission. Both strategies put a focus on the optimization of combustion system. In this study, a ULPC bowl concept applied in the previous works has been successfully verified in 11 L heavy-duty diesel engine with wellvalidated 3D combustion simulation, and the ULPC bowl shape has been geometrically optimized. A rough 0D calculation is used to calculate the fuel split ratio of the various ULPC bowl shapes. In the rated-power operating condition of the final Tier 4 engine which is deduced by 1D cyclic simulation, the optimal fuel split ratio of the injected fuel has been verified. Also, additional geometric optimization has been achieved without changing the optimal fuel split ratio. From these results, soot has been reduced by about 30% with ULPC optimum bowl shape against the Tier 3 re-entrant bowl shape.

베트남 공정무역의 발전: 공정무역조직 사례연구

김선화 ( Kim Sunhwa ),황선영 ( Hwang Seonyoung ),응우엔하프엉 ( Nguyen Haphuong ),장승권 ( Jang Seungkwon ) 한국동남아학회 2018 동남아시아연구 Vol.28 No.2

본 논문은 베트남의 공정무역조직들의 발전 사례를 통해 현재 베트남 공정무역의 현황과 특수성, 그리고 시사점을 토론한다. 베트남은 사회주의 시장경제 하에 급격한 경제성장을 이뤄왔으나 동시에 빈부격차의 문제도 겪고 있다. 소수민족이나 산간지역의 농업분야 생산자들의 빈곤문제가 커져가고 있다. 초기의 공정무역은 북반구 자선단체나 개발협력단체들에 의해 도입 되었고 지금도 그들이 주도한다. 이에 비해 베트남의 경우, 1990년대 말부터 자발적 동기를 가진 베트남인들에 의해 공정무역이 도입되었다. 이런 측면에서 남반구의 다른 공정무역 생산국과 베트남 사례는 다르다. 이 과정에서 공정무역조직들은 다양한 방식으로 공정무역을 실천하고 있었다. 공정무역 생산국에 관한 연구는 주로 아프리카와 남미를 대상으로 하고 있으며, 주제 또한 생산자들에게 미치는 영향에 관한 것이었다. 생산국의 공정무역조직을 분석하고 이들이 공정무역을 시작하게 된 동기와 발전과정을 연구한 것은 많지 않다. 본 연구는 베트남 공정무역조직들을 사례연구를 통해 분석하고, 이로부터 도출되는 조직의 특수성을 통해 현재 베트남의 공정무역을 설명하고자 한다. 본 연구는 베트남에서 전개되고 있는 공정무역에 대한 이해를 돕고, 공정무역 생산국에 관한 연구에 기여할 수 있을 것이다. This research is concerned with the current state and uniqueness of Vietnam’s Fair Trade through the case study of Fair Trade Organizations (hereafter FTOs) in Vietnam. Vietnam has emerged a successful developing country with rapid economic growth under the socialist regime, while the income gap between the rich and the poor is still growing. Especially the poverty is becoming a serious issue for ethnic minorities and smallholder farmers in the mountainous areas. Fair Trade in the early stage has been initiated, and still is led by the charities and international development agencies of the Global North. But Vietnam’s Fair Trade has been introduced by local Vietnamese who have been motivated to solve their own problems voluntarily. This is different from other Fair Trade producing countries in the Global South. It’s noticeable that Vietnam’s FTOs are playing a significant role of adopting and applying Fair Trade practices. Concerning Fair Trade producing countries the researchers are mostly focusing on Africa and Latin America and the themes are mainly to do with the impact of Fair Trade producers. There are very few research outcomes on the analysis of producing countries’ FTOs and their motives and developing processes. The research findings can contribute to understand not only Vietnam’s challenges and issues, but also Fair Trade producing countries in general.

섹터커플링 기술동향과 전력분야 추진 방안

이학주(Hakju Lee),황성욱(Sungwook Hwang),진윤선(Yunsun Jin),양승권(Seungkwon Yang) 대한전기학회 2022 전기의 세계 Vol.71 No.2