도시 소각로 시설의 고형 쓰레기 연소 후 생성된 바닥재 시료에 대한 다이옥신과 퓨란류의 분석

장윤석,홍종기,김진영,Chang, Yoon-Seok,Hong, JongKi,Kim, Jin-Young 대한화학회 1995 대한화학회지 Vol.39 No.7

다이옥신은 환경에 미량으로 존재하며 직접, 간접적인 경로를 통해 인체로 들어와 심각한 문제를 일으키는, 화학적으로 안정하고 잔류성과 독성이 강한 오염물질이다. 쓰레기 처리를 위한 소각로 시설은 다이옥신에 대한 대기오염의 주원인으로 알려져 있는데 연소시 소각로내에서와 배기가스 제어과정 중 다이옥신이 발생되는 것으로 보고되고 있다. 본 연구에서는 쓰레기 소각로에서 연소 후 생성된 바닥재 시료를 채취하여 다이옥신과 퓨란류를 조사하였다. 시료의 전처리는 EPA방법을 개선하여 불필요한 과정을 생략하면서 높은 회수율을 유지하였고 최종 정량은 고분해능 기체 크로마토그래피/고분해능 질량분석기(HRGC/HRMS)를 이용하여 분석하였다. 바닥재 시료를 분석한 전체 다이옥신의 양은 8.05 ng/g, 퓨란은 4.75 ng/g정도이었으며 2,3,7,8-TCDD는 6.93 pg/g이 검출되었고 염소원자 가 6~7개 치환된 다이옥신과 퓨란이 가장 많이 검출되는 경향을 볼 수 있었다. Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) are the most concerned toxic organic pollutants to human. Because of their extremely high toxicity and uncertain genotoxic potential, their determination in environmental and biological samples is of great interest. Municipal solid waste incinerator facilities have been reported as the major contributors of dioxins and furans to the environment, and their formation from combustion is a universal phenomenon, everywhere. In this study dioxins and furans were analyzed from the bottom ash produced during combustion in an municipal waste incinerator located in Seoul. The EPA method was modified for sample pretreatment: the soxhlet method was used for extraction and clean-up procedures were performed by using silica and basic alumina, excluding active-carbon. The extract was then analyzed by HRGC/HRMS. A general trend of increase in the amounts of 6∼7 chlorine-substituted dioxins and furans was observed. Total dioxins, furans and 2,3,7,8-TCDD were determined as 8.05 ng/g, 4.75 ng/g, and 6.93 pg/g, respectively.

원자력 배관재료의 파괴저항곡선 예측

장윤석,석창성,김영진,Chang, Yoon-Suk,Seok, Chang-Sung,Kim, Young-Jin 대한기계학회 1997 大韓機械學會論文集A Vol.21 No.11

In order to perform leak-before-break design of nuclear piping systems and integrity evaluation of reactor vessels, full stress-strain curves and fracture resistance (J-R) curves are required. However it is time-consuming and expensive to obtain J-R curves experimentally. The objective of this paper is to modify two J-R curve prediction methods previously proposed by the authors and to propose an additional J-R curve prediction method for nuclear piping materials. In the first method which is based on the elastic-plastic finite element analysis, a blunting region handling procedure is added to the existing method. In the second method which is based on the empirical equation, a revised general equation is proposed to apply to both carbon steel and stainless steel. Finally, in the third method, both full stress-strain curve and finite element analysis results are used for J-R curve prediction. A good agreement between the predicted results based on the proposed methods and the experimental ones is obtained.

시험관아기 프로그램에서 과배란유도 약제의 종류에 따른 황체기 혈청 난포호르몬 및 황체호르몬의 변동에 관한 비교연구

장윤석,신창재,김정구,문신용,이진용,김학순,Chang, Yoon-Seok,Shin, Chang-Jae,Kim, Jung-Gu,Moon, Shin-Yong,Lee, Jin-Yong,Kim, Hak-Soon 대한생식의학회 1989 Clinical and Experimental Reproductive Medicine Vol.16 No.1

Steroid hormone profiles during luteal phase of clomiphene citrate(CC)/human menopausal gonadotropin(hMG)/human chorionic gonadotropin(hCG)-stimulated in vitro fertilization (IVF) cycles and of follicle-stimulating hormone(FSH)/hMG/hCG-stimulated IVF cycles were compared. In seventy three cycles stimulated with CC/hMG/hCG regimen, follicles were aspirated during exploratory laparotomy and yielded 7 pregnancies, and in 83 cycles stimulated with FSH/hMG/hCG regimen, follicles were aspirated by laparoscope and made 13 pregnancies. Serum estradiol($E_2$) and progesterone($P_4$) levels were determined on days 2, 5, 7, and 9 after follicle aspiration. The FSH/hMG/hCG regimen was more effective than the CC/hMG/hCG regimen in folliculogenesis, ie, ovarian stimulation, follicular phase $E_2$ peak levels, oocyte maturation, and the number of retrieved oocytes. There was no significant difference between luteal serum $P_4/E_2$ ratio of the two regimens, suggesting that secretory endometrial build-up ability for implantation may not differ each other. Several significant correlations were observed between follicular phase seum $E_2$ peak levels and luteal phase serum $E_2$ and $P_4$ levels in the FSH/hMG/hCG-stimulated cycles but any correlation was not significant in the CC/hMG/hCG-stimulated cycles, suggesting that somewhat more follicles may eventually fall in atresia even after attaining dominant stage in the CC/hMG/hCG-stimulated cycles than the FSH/hMG/hCG-stimulated cycles.

입력신호 그룹화 방법에 의한 BIST의 테스트 시간 감소

장윤석,김동욱,Chang, Yoon-Seok,Kim, Dong-Wook 대한전자공학회 2000 電子工學會論文誌-SD (Semiconductor and devices) Vol.37 No.8

The representative area among the ones whose cost increases as the integration ratio increases is the test area. As the relative cost of hardware decreases, the BIST method has been focued on as the future-oriented test method. The biggest drawback of it is the increasing test time to obtain the acceptable fault coverage. This paper proposed a BIST implementation method to reduce the test times. This method uses an input grouping and test point insertion method, in which the definition of test point is different from the previous one. That is, the test points are defined on the basis of the internal nodes which are the reference points of the input grouping and are merging points of the grouped signals. The main algorithms in the proposed method were implemented with C-language, and various circuits were used to apply the proposed method for experiment. The results showed that the test time could be reduced to at most $1/2^{40}$ of the pseudo-random pattern case and the fault coverage were also increased compared with the conventional BIST method. The relative hardware overhead of the proposed method to the circuit under test decreases as th e size of the circuit to be tested increases, and the delay overhead by the BIST utility is negligible compared to that of the original circuit. That means, the proposed method can be applied efficiently to large VLSI circuits. 집적도 증가에 따라 비용이 증가하는 가장 대표적인 분야가 테스트 분야이며, 하드웨어 비용의 상대적인 감소에 따라 BIST 방법이 미래지향적 테스트 방법으로 지목받고 있다. 이 방법이 가지는 가장 큰 단점은 만족할 만한 고장검출률을 얻기 위해 필요한 테스트 시간의 증가이다. 본 논문에서는 BIST의 실현에 있어서 테스트 시간을 감소시키는 방안을 제안하였다. 이 방법은 입력의 그룹화와 테스트 포인트 삽입 방법을 사용하며, 테스트 포인트는 기존에 사용하던 것과는 다름 새로운 정의에 의해 결ㅈ어된다. 제안한 방법의 주요 알고리듬을 C-언어로 구현되었으며, 여러 가지 대상회로를 통해 실험한 결과 의사-무작위 패턴을 사용하는 경우에 비해 최대 $10^7$ 정도의 테스트 시간 감소를 가져올 수 있었으며, 고장검출률 또한 기존의 BIT방법보다 큰 것으로 확인되었다. 제안한 방법의 대상회로에 대한 상대적인 하드웨어 오버헤드는 대상회로가 커질수록 감소하고 지연시간 증가는 대형회로의 지연시간에 비해 미미한 것이어서, 대형회로를 BIST 방법에 의해 테스트할 때 제안한 방법이 매우 효과적일 것으로 사료된다.

자궁내막기질인 Type I Collagen을 이용한 생쥐 배아의 착상에 관한 연구

김정훈(Chung Hoon Kim),채희동(Hee Dong Chae),강병문(Byung Moon Kang),장윤석(Yoon Seok Chang),강은희(Eun Hee Kang),전용필(Yong Pil Cheon),박견(Kyun Park) 대한산부인과학회 2000 Obstetrics & Gynecology Science Vol.43 No.1

목적: Type I collagen을 이용하여 3차원적 배양체계와 유사한 구조적인 환경을 조성하여 생쥐 배아의 착상전후의 상태를 보기 위한 연구를 중심으로 하였다. 연구방법: 포배단계의 배를 획득하기 위해서 자궁과 수란관의 일부를 적출하고 배양액으로 관류하여 배를 획득한 후 실험에 사용하였다. 멸균된 centrifuge용 시험관에 collagen이 polymerization되게 하였다. 배아는 착상과정의 비교를 위하여 type I collagen군(실험군)과 대조군으로 나누었으며, 대조군에서는 type I collagen 없이 배양액만 사용하여 배아를 배양하였다. 배의 성장과 분화는 24시간 단위로 해부현미경하에서 관찰하였다. 결과: 배양 제 3일에 배아의 부착율은 차이가 없었으나, 배아의 크기는 대조군에 비하여 실험군에서 뚜렸하게 컸다. 배아의 성장이 대조군에서 배양용기의 표면을 따라 수평적으로 진행되는 것과는 달리 실험군에서는 구형을 이루며 입체적으로 성장하기 때문에 색깔이 훨씬 진하게 나타났다. 배아의 발달단계를 관찰한 결과 배양 제 4일과 5일에는 실험군에서 대조군에 비하여 유의하게 발달단계가 높았다. 결론: Type I collagen을 사용한 본 연구는 착상연구의 모델로서 실험적으로 원하는 환경을 설정할 수 있고 관찰이 용이한 장점을 보여주었으나, 생체의 자궁내막세포와 같은 dynamic milieu가 결여되어 있어, 실제의 자궁내막과 유사한 체계를 이루는 배양체계를 어느 정도 수준까지 완성하려면 지속적인 연구가 필요할 것으로 사료된다. Objectives: To examine the in vitro interactions of blastocyst attachment using type I collagen. Materials and methods: ICR mice were used and follicular growth was stimulated by pregnant mare serum gonadotropin and human chorionic gonadotropin. On day 4 of pregnancy, the uteri were removed and blastocysts were flushed. Mixtures of 1mL sterile water, 0.5mL DMEM, 2mL type collagen solution and 0.5mL 0.1M NaOH were prepared and transferred to an incubator where the collagen solution polymerized. Blastocysts were transferred to dishes previously coated with type I collagen. CMRL 1066 was used as the basic culture medium. It was supplemented with 1mM glutamine and 1mM sodium pyruvate plus 50 IU/ml penicillin and 50 mg/ml streptomycin. During the first 4 days the culture medium was supplemented with 20% fetal calf serum and thereafter with 20% heat inactivated human cord serum. All blastocysts were initially cultured for 2 days without media change. After 2 days, fresh medium was renewed daily. The stages of embryo growth were examined and recorded everyday under a dissecting microscope and classified according to the standard in vivo criteria set forth by Witschi. Results: By 48h, nearly all blastocysts had attached to the surface of collagen pad. Following adhesion to the collagen pad, the blastocysts maintained their 3-dimensional integrity in contrast to control. The embryos in collagen pad were not flattening and kept polarity and spherical shape during culture. The polar trophoblast invaded the type I collagen downward unlike the horizontal growth in control. In the developmental stage of mouse blastocyst, there were significant differences between control and type I collagen group during day 4 and 5 culture. Conclusion: Blastocyst development was better in type I collagen group than control. Therefore, in vitro culture study using type I collagen could provide improved model for the establishment of blastocyst implantation study.

제주도 농촌지역 소아에서 천식의 유병률과 흡입 알레르겐에 대한 감작률의 변화 - 3 년 간격의 단면조사

장윤석(Yoon Seok Chang),김상훈(Sang Hoon Kim),이명현(Myung Hyun Lee),김윤근(Yoon Keun Kim),조상헌(Sang Heon Cho),민경업(Kyung Up Mim),김유영(You Young Kim),홍성철(Sung Chul Hong),반준우(Joon Woo Bahn),김태범(Tae Bum Kim) 대한천식알레르기학회 2002 천식 및 알레르기 Vol.22 No.1

N/A N/A

알레르기질환 관련 Rhinovirus 연구의 최신 동향

장윤석 ( Yoon Seok Chang ) 대한천식알레르기학회 2010 천식 및 알레르기 Vol.30 No.2

Human rhinovirus (HRV) is a positive-sense single-stranded small RNA virus (7.2 kbp) in the Picornaviridae family and the genus Enterovirus. The complete genome sequences have recently been analyzed. Phylogeny shows 3 species: HRV-A, B and C. Another new potential species, HRV-D, has been suggested. HRV causes common cold, lower respiratory tract infection and acute virus-associated wheezing illness. HRV is the main triggering factor of asthma and COPD exacerbation. Recent epidemiologic studies suggested that HRV could initiate asthma. Host senses HRV via pattern recognition receptors such as TLR3, TLR7, TLR8, RIG-1 and MDA-5 which play important roles in HRV-induced airway epithelial cell responses. HRV had been known to infect only humans and Chimpanzees because ICAM-1, the receptor for major HRV, showed severe variations among species. Studies on HRV have been performed in vitro using human primary cells or cell-lines as well as in vivo using a human experimental model. The murine models of HRV infection has recently been developed using human ICAM-1 transgenic mice and a using minor group of HRV which uses LDL receptors for entering host epithelium. Further studies are needed to elucidate underlying mechanisms and to develop new therapeutic strategies for common cold, lower respiratory tract infection, acute virus-induced wheezing illness and asthma. (Korean J Asthma Allergy Clin Immunol 2010;30:86-90)

폐경 전후 여성에서 생화학적 골대사지표들의 폐경기간에 따른 변화 양상에 관한 연구

추형식(Hyung Sik Chu),채희동(Hee Dong Chae),김정훈(Chung Hoon Kim),장윤석(Yoon Seok Chang),목정은(Jung Eun Mok),강병문(Byung Moon Kang),조준식(Jun Sik Jo),강은희(Eun Hee Kang) 대한산부인과학회 1998 Obstetrics & Gynecology Science Vol.41 No.12

N/A Changes of bone turnover with aging are responsible for bone loss and play a major role in osteoporosis. Among the early postmenopausal women, as are known by previous study, there are about 35% fast bone losers and bone turnover is more uncoupled in osteoporotic group than in normal control. So, early detection of such fast losers and women who have high turnover rate is important to prevent postmenopausal osteoporosis and spontaneous fracture. Dual-energy X-Ray absorptiometry (DEXA), however, cannot reflect current bone loss because changes in bone mineral density (BMD) are only seen after 1 or more years of bone densities declining. In this study, we have measured a battery of new sensitive and specific markers of bone turnover which reflect current bone loss. To investigate the changing pattern of those markers, 674 healthy women including 451 postmenopausal women were classified, according to their menopausal period (less than 5 years, 5-10 years, more than 10 years). Bone formation was assessed by serum osteocalcin (OC), bone-specific alkaline phosphatase (BSAP) and bone resorption by the urinary excretion of deoxypyridinoline (DPD), cross-linked N-telopeptide of type I collagen (NTX). All Biochemical markers, except OC, significantly increased after menopause (p < 0.05). NTX and BSAP remained elevated after 10 years of menopause. These data indicated that the overall rates of both bone formation and bone tesorption increased after menopause and remained high in elderly women.

Challenges in the treatment of chronic spontaneous urticaria: switching treatment by the allergist`s view

장윤석 ( Yoon-seok Chang ) 대한피부과학회 2017 대한피부과학회 학술발표대회집 Vol.69 No.1

Chronic spontaneous urticarial is a chronic, persistent allergic disease which affects the quality of lives of the patients. To treat chronic spontaneous urticarial, physicians should evaluate and aware the aggravating factors. Aspirin or Non-steroidal anti-inflammatory drugs (NSAIDs) can aggravate a portion of the patients. Stress often induces exacerbation of urticaria. Anti-histamines, especially non-sedative, second generation antihistamines, are the mainstay of the treatment in chronic spontaneous urticaria. Physicians can increase the dose of antihistamine or combine antihistamines if an antihistamine is not enough. H2 blockers, antagonists of another histamine receptor, or leukotriene receptor antagonists could be considered if the effect of antihistamines is not sufficient. Short-term systemic steroid is a usual treatment in resistant cases but it is not recommended to use systemic steroid for long term. Dapsone could be considered especially in neutrophilic chronic spontaneous urticaria. However, cyclosporin is more preferred choice in resistant cases. Omalizumab, an anti-IgE monoclonal antibody which targets Fc region of IgE, is a game changer in the treatment of chronic spontaneous urticaria. Omalizumab has been used for the treatment of severe asthma but showed nice clinical effect in the treatment of chronic spontaneous urticaria. Omalizumab has been recommended in clinical guidelines. Cost, treatment duration, and rare but critical side effect such as anaphylaxis should be considered when physicians prescribe omalizumab.

미세수술을 이용한 난관불임복원수술

장윤석 ( Yoon Seok Chang ) 대한보건협회 1983 대한보건연구 Vol.9 No.1