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.

두시 하태독법의 IL-4 활성 조절이 D. farinae 유도 아토피유사피부염 발병 조절에 미치는 효과

안상현,김재규,천진홍,김기봉,Ahn, Sang Hyun,Kim, Jae Kyu,Cheon, Jin Hong,Kim, Ki Bong 대한한방소아과학회 2017 대한한방소아과학회지 Vol.31 No.1

Objectives Hataedock method is a Korean medical therapy which removes fetal toxin by orally administering herbal decoction to neonates. This study was to observe skin damage and anti-inflammatory effect via regulating IL-4 activity in NC/Nga mice which were induced atopic dermatitis (AD)-like skin lesion by Dermatophagoides (D.) farinae after applying Douchi Hataedock method. Methods NC/Nga mice with 3 weeks of gestational age were used. Each 10 mice were allocated to the control group (Ctrl), the AD-induced group (AE), and the group which induced AD after administering Douchi extract (GT). After 4 weeks from administering Douchi extract to the mice, the primary AD was induced by applying D. farinae extract 6 times per week for 3 weeks and then the secondary AD was induced by the same method after 1 week from the primary AD induction. To identify the skin damage and anti-inflammatory effect, we observed LxR, IL-4, Fc ${\varepsilon}$ receptor, substance P, and $NF-{\kappa}B$. Results The GT group showed alleviation of skin injury and decrease in capillary angiogenesis. Stratum corneum damage, epithelial cell hyperplasia, lymphocyte infiltration, and capillary distribution relatively decreased in the GT group. LxR-positive reaction in the GT group were increased by 53% than that of the AE group. IL-4 production, $Fc{\varepsilon}$ receptor activity, and substance P-positive reaction in the GT group were decreased by 82%, 42%, and 82% respectively compare to those of the AE group. $NF-{\kappa}B$-positive reaction in the GT group were decreased by 15% compare to that of the AE group. Conclusions Hataedock method with Douchi extract alleviated AD via reducing inflammatory cytokines secreted at the early stage of AD. Thus, Douchi Hataedock method has a beneficial effect for the prevention and treatment of AD.

백호탕 추출물의 지방장벽 손상 개선을 통한 상피 내 Th2 분화 조절 효과

안상현,김기봉,정아람,Ahn, Sang Hyun,Kim, Ki Bong,Jeong, Aram 대한한방소아과학회 2021 대한한방소아과학회지 Vol.35 No.4

Objectives The purpose of this study is to confirm the regulate effect of T helper (Th) 2 differentiation that Baekho-tang extract may produce to improves skin lipid barrier damages. Methods Four-weeks-old NC/Nga mice were divided into four groups: control group (Ctrl, n=10), lipid barrier eliminated group (LBE, n=10), Dexamethasone treatment after lipid barrier elimination group (DxT, n=10), and Baekho-tang extract treatment group after lipid barrier elimination group (BHTT, n=10). Baeko-tang extract was administered for 3 days after removal of the skin fat barrier in BHTT group. Then, we identified changes in external symptoms of the skin, factors affecting skin barrier such as potential of hydrogen (pH), filaggrin (FLG), transepidermal water loss (TEWL) and Th2 differentiation factors like Interleukin (IL)-4, Kallikrein Related Peptidase 7 (KLK7) and protease activated receptor 2 (PAR-2) through our immunohistochemistry. Results After lipid barrier elimination, the reduction of morphological skin inflammations was less in BHTT group than in LBE group and DxT group. Also, pH and TEWL were significantly decreased with BHTT group. However, FLG was significantly increased in BHTT group compared to LBE, DxT, and Ctrl group. All kinds of Th2 differentiation factors (IL-4, KLK7 and PAR-2) were also decreased in BHTT compared to the LBE and DxT. Conclusions As a result of this study, BHT administration decreased pH, TEWL, and increased FLG, thus participating in recovering damaged skin barrier. Since Th2 differentiation factors were decreased as well, BHT's regulatory effect in sequential immune reactions may be a possible explanation of how it enhances recovery of the damaged lipid barrier.

MANET 환경에서 주소 영역기반 주소할당 분산기법

안상현,임유진,유현,Ahn, Sang-Hyun,Lim, Yu-Jin,Yu, Hyun 한국정보처리학회 2009 정보처리학회논문지 C : 정보통신,정보보안 Vol.16 No.6

시간과 장소에 상관없이 인터넷 서비스를 제공 받고자 하는 인터넷 사용자들의 요구가 증가함에 따라 MANET(Mobile Ad-Hoc Network) 환경에서도 인터넷 연결성을 제공하기 위한 연구들이 주목을 받고 있다. 기존 DHCP(Dynamic Host Configuration Protocol) 기반 방식의 경우는 망 내 노드들에게 주소를 할당하기 위하여 다중 홉 거리에 있는 DHCP 서버와 메시지를 교환해야 하기 때문에 메시지 손실이 쉽게 발생할 수 있으며, 이로 인해 주소 설정의 안정성이 감소하고 주소 설정 시간이 증가하는 문제점이 있다. 따라서 본 논문에서는 노드가 DHCP 서버로부터 하나의 주소만을 할당 받는 것이 아니라 일정 크기의 주소 영역을 할당 받을 수 있게 하였다. 또한 주소 영역을 할당 받은 노드가 이웃의 주소 요청 노드들에게 자신의 주소 영역 중 일부를 할당할 수 있도록 하는 새로운 주소 설정 기법을 제안하였다. 모의 실험을 통하여 제안 기법이 기존 DHCP 기법에 비하여 주소 설정 시간과 제어 메시지 수 측면에서 각기 77%와 61%의 성능을 향상시킬 수 있음을 보였다. As it becomes increasingly important that Internet access is available anywhere at any time, providing MANET (Mobile Ad-Hoc Network) with the Internet access attracts more attention. The existing DHCP (Dynamic Host Configuration Protocol) address configuration schemes require message exchanges between MANET nodes and the DHCP server through multi-hop routes. Messages can be easily dropped in the wireless multi-hop communication environment and the address configuration may be instable and need long delay. In this paper, we propose a new address configuration scheme using the concept of address pool allocation. In the proposed scheme, the DHCP server assigns a part of its address pool to a node instead of a single address and the node can assign a part of its own address pool to its neighbor nodes. Through simulation studies, we show that our scheme yields about 77% of the address configuration delay and 61% of the control message overhead of the existing DHCP based mechanism.

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

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.

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.

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.

황련감초 하태독법과 프로바이오틱스의 대장점막 내 면역조절 효과 비교연구

안상현,차호열,김기봉,Ahn, Sang Hyun,Cha, Ho Yeol,Kim, Ki Bong 대한한방소아과학회 2017 대한한방소아과학회지 Vol.31 No.2

Objectives Hataedock is a treatment that dispels toxic heat and meconium which has been accumulated to the fetus from a pregnant mother via orally administering herbal extracts to a newborn baby. This study was conducted to compare the efficacy of Hataedock, with using the extract of Coptis japonica & Glycyrrhiza uralensis, to the early administration of probiotics for immunomodulation in the intestinal mucosa. Methods NC/Nga mice were divided into three groups; Control group (no treatment), CGT group (3-week-old mice given the extract of Coptis japonica & Glycyrrhiza uralensis), and MBT group (3-week-old mice given a Bifidobacterium). After 2 weeks, the intestinal mucosa tissues of each group of mice were observed. Immunohistochemical staining for IL-4, IL-13, CD40, $Fc{\varepsilon}RI$, $p-I{\kappa}B$, EGF, and VEGF in the intestinal mucosa was performed. Results CGT group showed 65% decrease in IL-4, 67% decrease in IL-13, 58% decrease in CD40, 72% decrease in $Fc{\varepsilon}RI$, 76% decrease in $p-I{\kappa}B$, 41% increase in EGF and 100% increase in VEGF compared to the control group. MBT group also showed 50% decrease in IL-4, 63% decrease in IL-13, 33% decrease in CD40, 53% decrease in $Fc{\varepsilon}RI$, 46% decrease in $p-I{\kappa}B$, 23% increase in EGF and 151% increase in VEGF compared to the control group. Conclusions These results suggest that both Hataedock, with using the extract of Coptis japonica & Glycyrrhiza uralensis, and early administration of probiotics were effective in regulating Th2, relieving inflammation and developing intestinal mucosal tissues. Hataedock with extract of Coptis japonica & Glycyrrhiza uralensis may be more effective for immunomodulation in intestinal mucosa than probiotics.