인산형 연료전지의 가스확산전극의 구조개선과 전기화학적 특성평가

안상현,심재철,유덕영,김인,이주성 ( Sang Hyun Ahn,Jae Cheol Shim,Duck Young Yoo,In Kim,Ju Seong Lee ) 한국공업화학회 1997 한국공업화학회 연구논문 초록집 Vol.1997 No.0

차량 애드혹 네트워크에서 차량 자체 정보를 기반으로 한 클러스터링 기법

안상현,임유진,Ahn, Sang-Hyun,Lim, Yu-Jin 한국정보처리학회 2011 정보처리학회논문지 C : 정보통신,정보보안 Vol.18 No.6

차량 애드혹 네트워크 환경에서 브로드캐스트 메시지 전송을 위한 효율적인 기법으로 클러스터링 기법이 있다. 대부분의 클러스터링 기법들은 안정적인 클러스터 구성을 위해 차량들 간에 정보를 교환하거나 이동성 정보를 계산하는 오버헤드를 야기한다. 이러한 오버헤드를 줄이기 위해 차량의 절대 속도를 기반으로 클러스터를 구축하는 CF-IVC[1]가 제안되었으나, CF-IVC의 경우 도로 혼잡 상황이나 운전자의 운전 행태를 고려하지 않음으로써 클러스터를 비효율적으로 구성하는 문제가 있다. 따라서 본 논문에서는 도로의 최고 제한 속도 및 도로 혼잡 상황을 고려한 차량 자체 정보 기반의 효율적인 클러스터 구축 기법을 제안한다. 제안 방식을 simple 플러딩 및 CF-IVC와 NS-2 시뮬레이션을 통해 비교함으로써 성능의 우수성을 입증한다. In the vehicular ad hoc network environment, the clustering mechanism is one of the efficient mechanisms to deliver broadcast messages. Most clustering mechanisms require message exchanges between vehicles to build stable clusters, which causes overhead. In order to reduce this overhead, CF-IVC [1] proposes the mechanism to construct clusters based on the vehicle speed. However, since CF-IVC does not consider the road traffic condition and the driver's behavior, it may result in inefficient clusters. Therefore, in this paper, we propose a mechanism to establish efficient clusters based on the vehicle local information with considering the road maximum speed limit and the road traffic condition. The performance of the proposed mechanism is validated by comparing with those of the simple flooding and CF-IVC through NS-2 simulations.

거대 마젤란 망원경의 논문 생산성 예측

안상현,박병곤,김영수,천무영,김호일,성현일,이동욱,김상철,Ahn, S.H.,Park, B.G.,Kim, Y.S.,Chun, M.Y.,Kim, H.I.,Sung, H.I.,Lee, D.W.,Kim, S.C. 한국천문학회 2008 天文學論叢 Vol.23 No.2

Productivity of the Giant Magellan Telescope is estimated based on the annual number of papers produced by the currently operating large telescopes such as the telescope at the ESO La Silla observatory, CFHT, AAT, the Magellan telescopes, ESO VLT, Japanese Subaru, the Gemini telescopes, and the Keck telescopes. We find that the amount of papers produced by a large telescope is roughly proportional to the diameter of its primary mirror. With this fact, we estimate the SCI-paper productivity of the Giant Magellan Telescope by extrapolating the productivity of the above-mentioned large telescopes. Moreover, according to the paper written in 2001 by Benn and Sanchez, the amount of highly-cited papers produced by a large telescope is roughly proportional to the light-gathering power of the telescope or the square of the diameter. Hence, we survey the productivity of Nature-class papers of the large telescopes and extrapolate the relationship to estimate the productivity of the Nature-class papers by using the Giant Magellan telescope of a filled aperture 21.4 meters in diameter. We expect that Korean astronomers will be able to produce annually 60 SCI-class papers and 20 Nature-class papers with high scientific impact by using the telescope-time corresponding to the 10% share of the Giant Magellan Telescope.

PKC 활성 조절을 통한 두시 하태독법의 항염증작용이 Mite 항원 유도 아토피유사피부염 발병 조절에 미치는 효과

안상현,김기봉,Ahn, Sang Hyun,Kim, Ki Bong 대한한방소아과학회 2016 대한한방소아과학회지 Vol.30 No.4

Objectives Hataedock (HTD) is an oral Korean herbal medical oral treatment that removes fetal toxic heat and meconium from new born babies. The purpose of this study is to evaluate whether Hataedock treatment of Duchi extracts has anti-inflammation effects in atopic dermatitis-like skin lesions in House Dust Mite-Induced NC/Nga Mice. Methods The mice were divided into 3 groups (n=10 per group) as follows: the control group (Ctrl group), AD-induced group (AE group), AD-induced with HTD treatment group (DT group). 3-week-old NC/Nga mice were introduced to Hataedock treatment, made of Duchi extract. After 4 weeks, House Dust Mite-Induced application was used six times per week for 3 weeks to induce the first atopic dermatitis, and second AD in 7 weeks after. To examine skin injuries and anti-inflammatory effect, PKC, MMP-9, iNOS immunohistochemistry were used. Results The alleviate effect of the skin damage and angiogenesis was observed in DT group. The damage of stratum corneum, hyperplasia, edema, infiltration of lymphocytes and distribution of capillary were decreased in DT group. Also, the study results suggested that Hataedock treatment made of Duchi extracts in DT group remarkably decreased skin damages by 51% (p < 0.001), as well as PKC by 91%, MMP-9 by 48% (p < 0.001), iNOS by 51% (p < 0.001). Conclusions Based on the study results, we observed that Hataedock treatment of Duchi extracts alleviates AD by diminishing various inflammatory cytokines, initial steps of AD development, in the skin lesions. Potential applications for prevention and treatment of atopic dermatitis are expected.

포스터 발표 - 무기재료분과 / 전기화학분과 / 촉매분과 : 인산형 연료전지의 가스확산전극의 구조개선과 전기화학적 특성평가

안상현,심재철,유덕영,김인,이주성 ( Sang Hyun Ahn,Jae Cheol Shim,Duck Young Yoo,In Kim,Ju Seong Lee ) 한국공업화학회 1997 한국공업화학회 연구논문 초록집 Vol.1990 No.3

황금 (Scutellaria baicalensis) 추출물의 ECS조절을 통한 아토피피부염 염증 완화 효과

안상현,김기봉,Ahn, Sang Hyun,Kim, Ki Bong 대한한방소아과학회 2021 대한한방소아과학회지 Vol.35 No.3

Objective The purpose of this study was to confirm the effect of Scutellaria baicalensis extract on skin damage recovery and inflammation relief in atopic dermatitis-induced mice through Endocannabinoid system (ECS) control. Methods 6-week-old Balb/C mice were divided into control group (Ctrl), atopic dermatitis induced group (ADE), palmitoylethanolamide (PEA) administered group after atopic dermatitis induced (PEAT), and Scutellaria baicalensis extract administered group after atopic dermatitis induced (SBT). Seven animals were assigned for each group. After drug administration for 3 weeks after inducing atopic dermatitis, Claudin and 8-OHdG were observed to confirm the recovery of the skin damage in each group. To confirm ECS regulation, CB1, CB2, and GPR55 were observed. To confirm the anti-inflammatory effect, Fc ε receptor, and MMP-9 was observed. Results Claudin positive reaction was significantly increased in SBT compared to ADE and PEAT. 8-OHdG positive reaction was significantly decreased in SBT compared to ADE and PEAT. CB1, CB2, and GPR55 positive responses were significantly increased in SBT compared to ADE and PEAT. Fc ε receptor and MMP-9 positivity were significantly decreased in SBT compared to ADE and PEAT. Conclusion It was confirmed that the Scutellaria baicalensis extract can reduce the inflammation of atopic dermatitis by restoring the structural damage of the skin lipid barrier through ECS activity.

강 슬리브 파단 직선 슬리브의 장력 및 열적 특성 분석 연구

안상현,김병걸,김상수,손홍관,박인표,김성규,Ahn, Sang-Hyun,Kim, Byung-Geol,Kim, Sang-Shu,Sohn, Hong-Kwan,Kim, In-Pyo,Kim, Sung-Kyu 한국전기전자재료학회 2008 전기전자재료학회논문지 Vol.21 No.11

According to previous report, aged sleeves of old transmission line showed several defaulted installation patterns, which was biased or corrosive-fractured of steel sleeve installed cases. These defects can cause serious accidents such as rapid increasing of sag or falling out of overhead conductor from sleeves. Consequently, the defects lead to the major power outage. Corrosion of steel sleeve is a typical defect by aging of sleeves. And it occupied almost 25 percent of investigated aged sleeves. This paper studied thermal properties and tension for ACSR conductor in case of fractured steel sleeve model by corrosion. The temperature distribution within overhead conductor has a specific gradient. Thermal properties of splice connectors(sleeve and clamp) showed normal behavior. However, mechanical properties were worse than normal sleeves. The detailed results were presented in the text.

다발성 용종의 형태로 발현된 위유암종(Gastric Carcinoid Tumor)의 수술적 치료 1예

안상현,김종원,이인규,이혁준,김우호,이건욱,양한광,Ahn, Sang-Hyun,Kim, Jong-Won,Lee, In-Kyu,Lee, Hyuk-Joon,Kim, Woo-Ho,Lee, Kuhn-Uk,Yang, Han-Kwang 대한위암학회 2007 대한위암학회지 Vol.7 No.2

위에 발생하는 유암종(carcinoid tumor)은 위저부에 있는 장크롬친화 유사 세포(enterochromaffine-like cell)의 증식에 의해 발생하는 종양이다. 위유암종은 모든 위 신생물의 2% 이내로 드문 질환이나 최근 발생률이 증가하고 있다고 한다. 저자들은 다발성 용종의 형태로 발현된 위유암종을 1예 경험한 바 있어 이를 보고하는 바이다. 29세 여자가 3년 전 실신을 주소로 외부병원을 방문하여 시행한 혈액검사 상 혈색소 6.0 g/dl로 측정되었다. 위내시경 상 출혈을 동반한 용종성 병변이 관찰되었고, 내시경적 결찰술로 지혈하였다. 당시 시행한 병리조직 검사 상 유암종으로 진단되었다. 추적 관찰 중 용종성 병변의 출혈로 인한 철결핍성 빈혈이 계속되어 본원으로 전원되었다. 위내시경 상 중체부에서 분문부에 걸쳐 20개 이상의 크기가 다양한 용종성 병변들이 관찰되었다. 혈색소 수치는 9.0 g/dl이었다. 출혈을 동반한 다발성 용종성 위유암종 진단 하에 위전절제술을 시행하였다. 조직검사 결과 위유암종으로 진단되었고 림프절 전이는 없었다. 수술 18개월 후 혈색소 12.8 g/dl로 측정되었고 복부 초음파 상 재발 소견은 없었다. 본 증례와 같이 위에 다발성으로 발생한 용종 형태의 유암종이 지속적인 출혈을 동반하여 만성적인 빈혈을 유발하는 경우 적극적인 수술적 치료를 고려해야 한다. Gastric carcinoid tumor is a neoplasm that arises from enterochromaffine-like (ECL) cells in the gastric fundus. It is a rare disease that comprises less than 2% of all gastric neoplasms; however its incidence has been recently increasing. We experienced one case of gastric carcinoid tumor that was revealed to be multiple polypoid lesions. A 29-year-old female patient visited a hospital three years ago due to syncope. The blood hemoglobin was measured as 6.0 g/dl. Gastroscopy revealed multiple polypoid lesions with bleeding; therefore endoscopic clipping was performed. The polyps were diagnosed as carcinoid tumor via endoscopic biopsy. She was transferred to our hospital because of persistent iron deficiency anemia that was caused by bleeding at the gastric polyps. Gastroscopy revealed more than twenty various-sized polypoid lesions from the mid-body to the antrum. The blood hemoglobin level was 9.0g/dl. Total gastrectomy was performed under the diagnosis of gastric carcinoid tumor with bleeding. All of the gastric polyps were diagnosed as carcinoid tumors, and any metastasis to the regional lymph nodes was not found. Eighteen months after operation, the blood hemoglobin was increased to 12.8g/dl with no evidence of recurrence. Surgical resection should be considered for treating gastric carcinoid tumor with continuous bleeding.

견우성의 이중적 의미에 대한 해석

안상현,김동빈,이용삼,송두종,Ahn, Sang-Hyeon,Kim, Dong-Bin,Lee, Yong-Sam,Song, Doo-Jong 한국천문학회 2010 天文學論叢 Vol.25 No.4

The Cowherd Star and the Weaving Maid Star have been famous stars in East Asian countries. Nowadays Altair is defined to be the Cowherd Star in public materials including science books, mass media, public outreach programs, and movies played in public planetariums and science museums. However, in astronomical books and star-charts in history, the Cowherd Big Star (牽牛大星) has been known to be Dabih or $\beta$ Cap in the constellation Capricorn, and the asterism Cowherd consists of six stars including Dabih. Since the same title is given to the different objects simultaneously, considerable misunderstanding and confusion among the public have occurred. In this paper we consider this problem in two aspects. One aspect is which star has been defined to be the Cowherd Star in ancient literatures; the other is which stars were regarded as the Cowherd or the Cowherd Star in the historical records of occultation or conjunction in History of Koryo, Annals of the Choson Dynasty, and Daily Records of Royal Secretariat of the Choson Dynasty. As a result, we see that Altair has been regarded as the Cowherd Star in folklore and literature, but Dabih has been defined to be the Cowherd Big Star in astronomical works. An explanation proposed by previous researchers on the reason why such double meanings have been appeared is introduced. In the explanation, the fact that the Altair was defined as the Cowherd Star in ancient times had not been handed over properly, and the name of Cowherd was later put to the Dabih and its surrounding five stars to form one of 28 lunar lodges. Based upon these facts, we suggest the following ideas: (1) Altair should be introduced to be the Cowherd Star in public-friendly programs, and Dabih should be noticed to be the Cowherd Big Star in the field of history of astronomy. Dabih should be added as the astronomical Cowherd Big Star in academic books such as a dictionary of astronomical terminology. (2) The Korean pronunciation for Altair should be al-tear instead of al-tairu in accordance with the definition in the astronomical terminology dictionary compiled by the Korean Astronomical Society.

소풍도적산의 iNOS 발현과 NO 생성 억제가 아토피 피부염에 미치는 영향

안상현,김진택,Ahn, Sang-Hyun,Kim, Jin-Taek 대한한의학방제학회 2007 大韓韓醫學方劑學會誌 Vol.15 No.1

Inducible nitric oxide synthase (iNOS) are important inflammation enzyme and severe up-nitric oxide (NO) production by this enzyme has been intricated with pathogenesis of inflammation diseases as atopy dermatitis. The present study was designed in order to determine whether Sopungdojeok-san could inhibit atopy dermatitis through modulation of iNOS mRNA expression and NO production, We found that iNOS mRNA expression and NO production in RAW 264.7 macrophages stimulated with lipopolysaccharide dose-dependantly decreased by Sopungdojeok-san extract treatment (0.4 - 1.0 mg/ml). The distribution of iNOS positive reacted cell in atopy dermatitis elicited skin of mice were remarkably decreased by Sopungdojeok-san administration (2.5 ml/kg/day). The SOD ability of Sopungdojeok-san were dose-dependantly increased from 0.6 mg/ ml than butylated hydroxyanisole. These data likely indicate that Sopungdojeok-san may act as inflammatory regulator for atopy dermatitis may be possible to develop useful agent for chemopreventation of NO-intricate inflammatory diseases.