Education for a Safer World

Hosik Yoo 동아시아재단 2012 Global Asia Vol.7 No.1

Evaluation of Operational Options of Wastewater Treatment Using EQPS Models

Hosik Yoo,Seyoung Ahn 한국도시환경학회 2018 한국도시환경학회지 Vol.18 No.4

EQPS (Effluent Quality Prediction System, Dynamita, France) was applied to analyze the appropriateness of the design of a bioreactor in A sewage treatment plant. A sewage treatment plant was designed by setting the design concentration of the secondary clarifier effluent to total nitrogen and total phosphorus, 10 mg/L and 1.8 mg/L, respectively, in order to comply with the target water quality at the level of the hydrophilic water. The retention time of the 4-stage BNR reactor was 9.6 hours, which was 0.5 for the pre-anoxic tank, 1.0 for the anaerobic tank, 2.9 for the anoxic tank, and 5.2 hours for the aerobic tank. As a result of the modeling of the winter season, the retention time of the anaerobic tank was increased by 0.2 hours in order to satisfy the target water quality of the hydrophilic water level. The default coefficients of the one step nitrification denitrification model proposed by the software manufacturer were used to exclude distortion of the modeling results. Since the process modeling generally presents optimal conditions, the retention time of the 4-stage BNR should be increased to 9.8 hours considering the bioreactor margin. The accurate use of process modeling in the design stage of the sewage treatment plant is a way to ensure the stability of the treatment performance and efficiency after construction of the sewage treatment plant.

Association of AGT Polymorphisms with Benign Prostate Hyperplasia in Korean Population

Hosik Seok,Young Ock Kim,Sang Hyub Lee,Koo Han Yoo,Byung-Cheol Lee,Hye Sook Jeon,Su Kang Kim,Joo-Ho Chung 대한스트레스학회 2013 스트레스硏究 Vol.21 No.2

많은 노화-연관 질환은 세포 수준에서의 스트레스 반응과 연관되어 나타나며, 중년 이후의 남성에서 발생하는 양성 전립선 비대증이 일으키는 하부 요로 비뇨기계 증상은 환자에게 지대한 스트레스를 초래한다. 양성 전립선 비대증은 흔한 남성성 질환이며 가족력이 위험 요소로 인정되고 있다. 다양한 양성 전립선 비대증의 위험 요소에는 많은 유전자와 세포 신호 체계가 연관될 것으로 여겨진다. 그 중 안지오텐시노겐은 혈관 질환에서 연구되어 온 주요 유전자이다. 안지오텐시노겐은 한편으로 다양한 전신질환에 영향을 줄 수 있는 것으로 밝혀져 왔으며, 이 유전자의 다형성은 노화-연관 질병과의 연관성이 있었다. 안지오텐시노겐과, 그에 연관되는 다른 스트레스 연관 유전자들의 신호체계는 양성 전립선 비대증의 발병에 영향을 줄 가능성이 있을 것으로 보인다. 하지만 양성 전립선 비대증에 대한 안지오텐시노겐 유전자의 다형성의 영향에 대한 연구는 이뤄져 있지 않고 있었다. 본 연구에서는 안지오텐시노겐 유전자 내의 두 개의 단일염기다형성(rs699와 rs4762)과 양성 전립선 비대증 간의 발병 및 임상 양상에 대한 연관성을 연구하기 위해 221명의 환자와 212명의 정상인에서 연관성 분석이 시행되었다. 이중 전립선 비대증 환자군은 네 가지의 임상적 특질[전립선 크기, 최대 요속(Qmax), 혈청내 전립선 특이 항원(PSA) 수치, 그리고 국제 전립선 증상 점수(IPSS)] 각각에 따라 두 군씩으로 분류하여 분석하였다. 그 결과로, rs699는 유전형과 대립형질 빈도에서 전립선 비대증의 발병과의 연관성만이 나타났다(p<0.05). 결론적으로, 본 연구의 결과는 안지오텐시노겐 유전자의 rs699 다형성은 한국인에서 양성 전립선 비대증의 발병에 영향을 주는 요소가 될 수 있음을 의미한다. Most of aging-related disorders are related with stress responses in cellular level. In males after middle age, benign prostate hyperplasia (BPH) may cause severe stress by lower urinary tract symptoms. BPH is common androgenic disorder and family history is an etiological factor. As BPH is a multifactorial disease, many genes and cellular pathways may affect the development. Among them, Angiotensinogen (AGT) was regarded important in vascular diseases. AGT also may affect various diseases throughout whole body organs and polymorphisms of AGT may be associated with aging-related morbidities. AGT and stress genes related to AGT signaling may play a role in the pathophysiology of BPH. However, there was no study of BPH regarding the effect of AGT polymorphisms. In this study, we nvestigated the association of two AGT single nucleotide polymorphisms (SNPs) (rs699 and rs4762) to the development and clinical features of BPH. A total of 221 BPH subjects and 212 control subjects were analyzed. The BPH patient group was divided into two groups based on each of clinical features [prostate volume, peak urinary flow rate (Qmax), serum prostate specific antigen (PSA) level, and international prostate symptom scores (IPSS)] to analyze the effect of the SNPs on each of clinical parameters. In the result, a missense SNP rs699 was only associated to the development of BPH in the genotypes and allele frequencies (p<0.05). In conclusion, we suggest that a missense SNP rs699 of AGT may affect the susceptibility to BPH in the Korean population.

Association of BID SNPs (rs8190315 and rs2072392) and clinical features of benign prostate hyperplasia in Korean population

Hosik Seok,Su Kang Kim,Koo Han Yoo,Byung-Cheol Lee,Young Ock Kim,Joo-Ho Chung 한국운동재활학회 2014 JER Vol.10 No.6

Distortions of iris and anterior lens capsule OCT images by ICRS.

Hwang, Hosik,Yoo, Young Sik,Park, Chang Won,Joo, Choun-Ki Slack Inc 2013 Journal of refractive surgery Vol.29 No.3

Safeguards Distinction in Water-Cooled SMRs

Kwangho Ju,Seungho Jeong,Hosik Yoo 한국방사성폐기물학회 2023 한국방사성폐기물학회 학술논문요약집 Vol.21 No.2

Small modular reactors (SMRs) are getting attention as an alternative to fossil fuel power stations due to versatile application and carbon dioxide reduction. Although various types of advanced reactors are being developed, water-cooled SMR will be first deployed on a commercial scale. The International Atomic Energy Agency (IAEA) and regulatory bodies are trying to identify safeguards issues of water-cooled SMRs as the first priority. IAEA begins to develop a safeguards plan by asking for the facility’s specification in a given format, a design information questionnaire (DIQ). Then, IAEA periodically performs safeguards activities such as design information verification (DIV) and physical inventory verification (PIV). In this sense, we utilize research and power reactor DIQ for water-cooled SMRs (NuScale, SMART, i-SMR and KLT-40S). Most of the questions are answered with open information. For undisclosed answers, pressurized water reactor (PWR) features are described. Safeguards issues in water-cooled SMR originate from core modularization. As the nuclear material flows are diversified, the number of safeguards measure will be increased while staff are reduced in SMRs. Instrumentation for safeguards should be developed to reduce worker’s fatigue level. Intensive arrangement of fuel assemblies may also need unique devices to secure their visibility or detectability. A transparent floor with a surveillance system or advanced Cherenkov viewing device may be adopted to enhance containment and surveillance. Meanwhile, some questions could be more elaborate regarding safeguards. First, question #38 cannot confirm the time of occurrence of weapon-grade plutonium for reactor operation. Second, the answers in questions #46 and #49 are primitive to identify a place to generate an undeclared fissile material. Therefore, the current DIQ should be revised to get a detailed burnup report and spatial distribution of neutron flux.

DEVELOPMENT OF A VULNERABILITY ASSESSMENT CODE FOR A PHYSICAL PROTECTION SYSTEM:SYSTEMATIC ANALYSIS OF PHYSICAL PROTECTION EFFECTIVENESS (SAPE)

SUNG SOON JANG,SUNG-WOO KWAK,HOSIK YOO,JUNG-SOO KIM,WAN KI YOON 한국원자력학회 2009 Nuclear Engineering and Technology Vol.41 No.5

A vulnerability assessment is essential for the efficient operation of a physical protection system (PPS). Previous assessment codes have used a simple model called an adversary sequence diagram. In this study, the use of a twodimensional (2D) map of a facility as a model for a PPS is suggested as an alternative approach. The analysis of a 2D model, however, consumes a lot of time. Accordingly, a generalized heuristic algorithm has been applied to address this issue. The proposed assessment method was implemented to a computer code; Systematic Analysis of physical Protection Effectiveness (SAPE). This code was applied to a variety of facilities and evaluated for feasibility by applying it to various facilities. To help upgrade a PPS, a sensitivity analysis of all protection elements along a chosen path is proposed. SAPE will help to accurately and intuitively assess a PPS.

Oxidative dehydrogenation of n-butane over Mg3(VO4)2/MgO–ZrO2 catalysts: Effect of oxygen capacity and acidity of the catalysts

Jong Kwon Lee,Howon Lee,Ung Gi Hong,Yeonshick Yoo,Young-Jin Cho,Jinsuk Lee,Hosik Chang,송인규 한국공업화학회 2012 Journal of Industrial and Engineering Chemistry Vol.18 No.5

X-Mg3(VO4)2/MgO–ZrO2 catalysts were prepared by a wet impregnation method with a variation of vanadium content (X = 2.8, 4.2, 5.6, 9.0, and 11.2 wt%), and they were applied to the oxidative dehydrogenation of n-butane. Effect of oxygen capacity and acidity of Mg3(VO4)2/MgO–ZrO2 catalysts on the catalytic performance in the oxidative dehydrogenation of n-butane was investigated. Experimental results revealed that oxygen capacity and acidity of catalyst were closely related to the catalytic performance in the oxidative dehydrogenation of n-butane. It was found that the catalytic performance of X-Mg3(VO4)2/MgO–ZrO2 catalysts increased with increasing oxygen capacity and with increasing acidity of the catalyst.

Mg3(VO4)2-MgO-ZrO2 nano-catalysts for oxidative dehydrogenation of n-butane.

Lee, Jong Kwon,Seo, Hyun,Hong, Ung Gi,Yoo, Yeonshick,Cho, Young-Jin,Lee, Jinsuk,Park, Gle,Chang, Hosik,Song, In Kyu American Scientific Publishers 2014 Journal of Nanoscience and Nanotechnology Vol.14 No.11

<P>A series of X-Mg3(VO4)2-MgO-ZrO2 nano-catalysts with different vanadium content (X = 3.3, 5.3, 7.0, 10.2, and 13.4) were prepared by a single-step citric acid-derived sol-gel method for use in the oxidative dehydrogenation of n-butane to n-butene and 1,3-butadiene. The effect of vanadium content of X-Mg3(VO4)2-MgO-ZrO2 nano-catalysts on their physicochemical properties and catalytic activities in the oxidative dehydrogenation of n-butane was investigated. Successful formation of X-Mg3(VO4)2-MgO-ZrO2 nano-catalysts was confirmed by XRD, Raman spectroscopy, and ICP-AES analyses. The catalytic performance of X-Mg3(VO4)2-MgO-ZrO2 nano-catalysts strongly depended on vanadium content. All the X-Mg3(VO4)2-MgO-ZrO2 nano-catalysts showed a stable catalytic performance without catalyst deactivation during the reaction. Among the catalysts tested, 7.0-Mg3(VO4)2-MgO-ZrO2 nano-catalyst showed the best catalytic performance in terms of yield for total dehydrogenation products (TDP, n-butene and 1,3-butadiene). TPRO (temperature-programmed reoxidation) experiments were carried out to measure the oxygen capacity of the catalyst. Experimental results revealed that oxygen capacity of the catalyst was closely related to the catalytic performance. Yield for TDP increased with increasing oxygen capacity of the catalyst.</P>