간단한 인증키 동의 프로토콜인 Kim-Kim-Hwang 방법의 안전성 고찰

김윤정;김영신;황준 서울여자대학교 컴퓨터과학연구소 2004 정보기술논문지 Vol.2 No.-

The Diffie-Hellman Key Exchange scheme can produce a common session key between the two communicators, but its problem is that it makes a man-in-the middle attack possible. To solve problems like these, several protocols have been put forward, and the Simple Authenticated Key Agreement (SAKA) Protocol is among them. Seo-Sweeney suggested a SAKA protocol initially and the protocol has weakness that a malicious 3rd party can masquerade a valid user. Tseng suggested another protocol that advances this problem but this protocol can still be attacked when the messages in key verification phase are identical. Ku-Wang suggested a new protocol that advances this problem. Kim-Kim-Hwang also suggested a new SAKA protocol and confirmed that their protocol has same safeness and better performance compared to the other SAKA protocols. In this paper, we reanalyze the safeness of SAKA protocols and find out that Kim-Kim-Hwang protocol has not only better performance but also better safeness. Diffie-Hellman의 키 인증 기법에 대한 제 3자 공격 (man-in-the middle attack)에 강한 간단한 인증키 동의 프로토콜인 SAKA (Simple Authenticated Key Agreement Protocol)가 제안된 바 있다. SAKA는 초기에 Seo-Sweeney에 의해 제안되었으며 이 방법은 침입자가 중간에 메시지를 가로채서 정당한 사용자임을 가장할 수 있는 단점이 있다. Tseng은 이 단점을 개선한 방안을 제안하였는데 이것도 키 확인 메시지 두 개의 값이 같을 경우 공격을 받을 수 있음이 밝혀졌다. Ku-Wang은 Tseng 방법의 문제점을 개선한 알고리즘을 제안하였다 그리고 Kim-Kim-Hwang은 새로운 SAKA 알고리즘을 제안하고 이것이 기존 SAKA 프로토콜들과 안전성은 동일하면서도 성능이 개선된 것임을 밝힌바 있다. 본 논문에서는 안전성 분석의 재고찰을 통하여, Kim-Kim-Hwang의 방법이 기존 SAKA 프로토콜들보다 성능면에서뿐만 아니라, 안전성 면에서도 우수함을 밝힌다.

섬유보강 다공성 옥상녹화 황토콘크리트의 물리·역학적 및 온도변화 특성 평가

오리온,김춘수,김황희,전지홍,권완식,박찬기,Oh, Ri On,Kim, Chun Soo,Kim, Hwang Hee,Jeon, Ji Hong,Kwon, Wan Sig,Park, Chan Gi 한국농공학회 2013 한국농공학회논문집 Vol.55 No.4

The physical, mechanical, water purification and temperature properties of fiber reinforced porous hwang-toh green roof concrete have been evaluated in this study. The effect of the depending on replacement ratio of blast furnace slag to cement was investigated such that the replacement ratio is varied to 0 % and 30 %. Also, the replacement ratios of hwang-toh were 0, 20 and 30 %. The polyvinyl alcohol fiber was used for the reinforcing fiber. A series of pH test, unit weight, void ratio, compressive strength, after purification and variation of temperature test have been performed to evaluate the performance, water purification effect and temperature properties of the fiber reinforced porous hwang-toh green roof concrete. The test results indicate that the physical and mechanical properties of fiber reinforced porous hwang-toh green roof concrete is affected by the replacement ratio of the blast furnace slag and hwang-toh contents. Results of purifying water showed that the water purification effect of porous hwang-toh green roof concrete is about 40 %. Also, the temperature properties test results indicate the green roof blocks using fiber reinforced porous hwang-toh green roof concrete have insulation and temperature reduction effect.

고로슬래그시멘트를 사용한 다공성 황토콘크리트의 성능 평가

김황희,강수만,박종식,박상우,전지홍,이진형,차상선,박찬기,Kim, Hwang-Hee,Kang, Su-Man,Park, Jong-Sik,Park, Sang-Woo,Jeon, Ji-Hong,Lee, Jin-Hyung,Cha, Sang-Sun,Park, Chan-Gi 한국농공학회 2010 한국농공학회논문집 Vol.52 No.3

This study aims to evaluate a porous concrete using hwang-toh, blast furnace slag and blast furnace slag (BFS) cement instead of type I cement. The tests that were carried out to analysis the properties of porous hwang-toh BFS cement concrete included compressive strength, continuous void ratio, absorption rate, and pH value, repeated freezing and thawing test were conducted. Test results indicated that the performance in porous hwang-toh concrete are effective on the kaoline based binder materials. The pH value were shown in about 9.5 ~ 8.5. The compressive strength was increased and void ratio was decreased with increasing the kaoline based binder materials, respectively. The void ratio and compressive strength were in the range of about 21 ~ 30 %, 8 ~ 13 MPa, respectively. The increased in void ratio of more than 25 % is showed to reduce the resistance of repeated freezing and thawing. Also, the resistance of repeated freezing of thawing and the compressive strength of porous hwang-toh BFS cement concrete are independent with hwang-toh content and BFS cement amount. But, the void ratio was decreased with increasing the high volume hwang-toh contents (more than 15 %).

황토골재를 사용한 콘크리트의 제특성에 관한 실험적 연구

황준필(Hwang, Jun Pil),김기범(Kim, Ki Beom),안기용(Ann, Ki Yong) 한국구조물진단유지관리학회 2009 한국구조물진단학회 학술발표회논문집 Vol.2009 No.2

For the characteristics of the concrete using Hwang-Toh aggregate, thermal Insulation capacity test, absorption capacity of heavy metals several test were performed. The study found that the Hwang-Toh concrete could improved the characteristics of conventional normal concrete. The Hwang-Toh concrete shows 67.7% lower thermal conductivity than normal concrete, so it shows good thermal insulation capacity. And the leaching test results showed that 96% of heavy metals such as Pb, Zn, Mn were absorbed by the Hwang-Toh concrete.

황토골재를 사용한 콘크리트의 제특성에 관한 실험적 연구

황준필 ( Hwang Jun Pil ),김기범 ( Kim Ki Beom ),안기용 ( Ann Ki Yong ) 한국구조물진단유지관리공학회 2009 한국구조물진단유지관리공학회 학술발표대회 논문집 Vol.13 No.2

For the characteristics of the concrete using Hwang-Toh aggregate, thermal Insulation capacity test, absorption capacity of heavy metals several test were performed. The study found that the Hwang-Toh concrete could improved the characteristics of conventional normal concrete. The Hwang-Toh concrete shows 67.7% lower thermal conductivity than normal concrete, so it shows good thermal insulation capacity. And the leaching test results showed that 96% of heavy metals such as Pb, Zn, Mn were absorbed by the Hwang-Toh concrete.

The expression patterns of RANKL and OPG in murine tooth eruption

Hwang, Kyung-Mun,Kim, Eun-Jung,Kim, Hyun-Jung,,Kim, Young-Jin,Nam, Soon-Hyeun 大韓小兒齒科學會 2006 大韓小兒齒科學會誌 Vol.33 No.2

치아의 맹출은 치아기 (dental organ)와 치조골의 세포와 연관된 매우 복잡한 과정이다. 우선 치아 맹출이 일어나기 전에 파골세포가 치낭으로 집결하게 된다. 이러한 치낭의 역할은 파골세포와 조골세포의 상호작용으로 이루어 지는 골개조와 밀접한 관련이 있는데, 이는 치아 맹출과 연관된 많은 유전자들이 치낭에서 발현되기 때문이다. RANKL는 TNF ligand family로써 조골세포에 존재하며 파골세포의 형성 및 전구세포로 부터의 활성화를 유도한다. 이러한 RANKL은 OPG에 의해 그 작용이 억제되며 RANKL와 OPG의 상대적인 비율이 파골세포의 형성에 영향을 미친다. 또한 Runx2유전자의 변이는 조골세포의 분화와 활성에 차질을 가져오고 결국 RANKL/OPG pathway를 통해 파골세포 형성에 영향을 줄 수 있다. 치아의 발육 및 맹출에 미치는 RANKL 및 OPG의 영향을 알아보고 Runx2와의 연관성을 알아보기 위해 in situ hybridization 방법으로 태생 1, 3, 5, 7, 9, 11일된 쥐의 하악 및 제1대구치를 사용하여 실험을 실시한 결과 RANKL, OPG, Runx2의 mRNA가 태생 1일부터 11일까지 치낭 및 치아주위조직에 특성있게 나타났다. 이중 태생 5일에서 9일 사이에 RANKL 및 Runx2는 치아의 교합면측과 하방 치조골 부위의 발현이 강하게 나타난 반면 OPG는 약한 발현을 보였다. 이는 또한 파골세포의 활성부위를 알아보기 위해 TRAP염색을 실시하여 태생 5일에서 9일 사이에 최대의 활성화를 나타낸 결과와 연광성 있게 나타났다. RANKL, OPG, Runx2의 특성있는 발현양상들을 종합해 볼 때, 치아 맹출은 치낭, 치아기, 치조골 사이의 상호 작용을 통해 이루어 지며, 이는 치낭이 치아 맹출에 있어서 매우 중요하다는 것을 의미한다. 또한, 이러한 유전자들 (RANKL, OPG, Runx2) 이 치아의 맹출에 중요한 역할을 하는 것으로 사료된다. Tooth eruption is a complex and tightly regulated process that involves cells of the tooth organ and the surrounding alveolus. Osteoclast precursors must be recruited into the dental follicle prior to the onset of eruption. This function of dental follicle may be regarded as the ability of bone remodeling characterized by the interaction of osteoclasts and osteoblasts. This is because tooth eruption is a localized event in which many of the genes required for eruption are expressed in the dental follicle. RANKL is a membrane-bound protein that is a member of the TNF ligand family, which is present on bone marrow stromal cells and osteoblasts, and induces osteoclast formation and activation from precursor cell. The biologic effect of RANKL is inhibited by OPG and, in bone, the relative ratio of RANKL and OPG modulates osteoclastogenesis. To evaluate the roles of RANKL and OPG in tooth eruption and the relations with the expression pattern of Runx2, in situ hybridization was performed with mandibles of mice at postnatal stage 1, 3, 5, 7, 9 and 11. mRNA of RANKL, OPG, and Runx2 are expressed in dental follicle and surrounding tissue from P1 to 11. To determine the sites of osteoclastic activity duing tooth eruption, mandibles were dissected. Peak osteoclastic activity in alveolar bone along the occlusal and basal regions was observed from P5 to 9, with osteoclasts in these regions being large and strongly TRAP-positive. The specific spatic-temporal expression patterns of RANKL, OPG and Runx2 in our study suggest that tooth eruption could be progressed through the interactions of molecular signaling among dental follicle, dental organ and alveolar bone, furthermore it means that dental follicle is quite important in tooth eruption. In addition, it indicates that these genes (RANKL, OPG, and Runx2) play critical roles in tooth eruption.

Increased Urinary KIM-1 and Tubular KIM-1 Expression in IgA Nephroapathy (초)

( Mi Seon Seo ),( Soon Hyo Kwon ),( Moo Young Park ),( Soo Jung Choi ),( Jin Seok Jeon ),( Hyun Jin Noh ),( Jin Gook Kim ),( Dong Cheol Han ),( Seung Duk Hwang ) 대한내과학회 2010 대한내과학회 추계학술대회 Vol.2010 No.-

간호 지식관리시스템 개발

민효숙,문원희,김미자,김선미,황윤신,황관옥,심희숙 충남대학교 간호과학연구소 2006 충남대 간호학술지 Vol.9 No.1

The purpose of this study were to develop Knowledge Management System for the nurse and to identify its effectiveness. The program was developed in development of the contents and programing. And the system was operated to 85 nurse for three weeks. Data collection were performed during the period of May 1, 2005 to December 30, 2005. The data was collected from 85 nurses using questionnaires. In order to ascertain the validity of clinical application of the system, Prior experience of the computer mediated communication, user satisfaction and utilization were analyzed. The instruments for the study were satisfaction(Kim, 2000), utilization(Kim, 2002). The collected data were analysed by descriptive statistics, using SPSS WIN 11.0 program. The results showed average score which is the satisfaction(6.09) showed middle satisfaction scores. It is concluded that if Nursing Knowledge Management System is operated considering all the above factors, It wound be one of the best qualified continuing clinical method for nurses.

국산·수입산 동부를 이용한 모시잎송편의 영양성분비교

김영섭,김소민,오지연,황진봉,이기택,신정아,김상천,김세나,김행란,황영,최용민 忠北大學校 農業科學硏究所 2015 農業科學硏究 Vol.31 No.2

Variation in clinical usefulness of biomarkers of acute kidney injury in young children undergoing cardiac surgery

Baek, Hee Sun,Lee, Youngok,Jang, Hea Min,Cho, Joonyong,Hyun, Myung Chul,Kim, Yeo Hyang,Hwang, Su-Kyeong,Cho, Min Hyun The Korean Pediatric Society 2020 Clinical and Experimental Pediatrics (CEP) Vol.63 No.4

Background: Acute kidney injury (AKI) is one of the most significant postoperative complications of pediatric cardiac surgery. Because serum creatinine has limitations as a diagnostic marker of AKI, new biomarkers including neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (KIM-1), and interleukin-18 (IL-18) are being evaluated to overcome these limitations and detect AKI at an early stage after cardiac surgery. Purpose: This study aimed to investigate the clinical usefulness of these biomarkers in young children. Methods: Thirty patients with congenital heart diseases who underwent cardiac surgery using cardiopulmonary bypass (CPB) were selected, and their urine and blood samples were collected at baseline and 6, 24, and 48 hours after surgery. Serum creatinine and blood urea nitrogen levels as well as NGAL, KIM-1, and IL-18 levels in urine samples were measured, and clinical parameters were evaluated. Results: Of the 30 patients, 12 developed AKI within 48 hours after cardiac surgery. In the AKI group, 8 of 12 (66.6%) met AKI criteria after 24 hours, and urine KIM-1/creatinine (Cr) level (with adjustment of urine creatinine) peaked at 24 hours with significant difference from baseline level. Additionally, urine KIM-1/Cr level in the AKI group was significantly higher than in the non-AKI group at 6 hours. However, urine NGAL/Cr and IL-18/Cr levels showed no specific trend with time for 48 hours after cardiac surgery. Conclusion: It is suggested that urine KIM-1/Cr concentration could be considered a good biomarker for early AKI prediction after open cardiac surgery using CPB in young children with congenital heart diseases.