양막을 이용한 각막 간질세포의 배양과 중배엽 줄기세포의 분화유도

박수현,전연숙,김재찬.Soo Hyun Park. MS. Yeoun Sook Chun. MD. PhD. Jae Chan Kim. MD. PhD 대한안과학회 2010 대한안과학회지 Vol.51 No.12

Purpose: To investigate the characteristics of cultured rabbit corneal keratocytes in vitro and evaluate the possibility of differentiation of mesenchymal stem cells to keratocytes using the keratocyte conditioned medium (KCM). Methods: Isolated keratocytes were seeded on the stromal side of amniotic membranes (AM) or plastic dishes, and morphologic changes were evaluated. Rabbit mesenchymal stem cells were cultured on AM with α-MEM (minimum essential medium alpha) and KCM. The gene expression patterns of specific keratocyte markers (keratocan, lumican, and aldehyde dehydrogenase family, member A1 (ALDH1A1)) of cultured cells were evaluated by RT-PCR. Results: Keratocytes on AM showed dendritic morphology with slow proliferation in contrast, cells on dishes were stellate in shape with fast proliferation. Cultured keratocytes on AM maintained the expression of keratocan, lumican and ALDH1A1 while keratocytes on plastic dishes steadily lost their keratocyte marker gene expression. Additionally, mesenchymal stem cells cultured with KCM on AM induced expression of keratocan and ALDH1A1. Conclusions: Keratocytes cultured on AM stromal matrix maintained their characteristic morphology and marker gene expression. Morphology changes and marker gene expressions of mesenchymal stem cells suggest an ability to differentiate into keratocytes when grown on AM with KCM. J Korean Ophthalmol Soc 2010;51(12):1652-1658

무차별 공격에 효과적인 다중 Address Space Randomization 방어 기법

박수현,김선일,Park, Soo-Hyun,Kim, Sun-Il 한국정보처리학회 2011 정보처리학회논문지 C : 정보통신,정보보안 Vol.18 No.2

Address Space Randomization(ASR)은 성능 부하가 없고 광범위한 데이터 메모리 영역의 보호가 가능한 우수한 방어 기법이다. ASR은 사용 가능한 데이터 메모리 영역 내에서 변수를 재배치 함으로써 공격자에게 변수의 주소를 숨기는데, 데이터 메모리 영역의 크기가 한정되어서 무차별 공격에 취약한 단점이 있다. 본 논문은 기존 ASR의 단점을 제거하기 위한 다중 ASR 기법을 제시한다. 다중 ASR 기법은 데이터 메모리 영역을 원본 및 복사 영역으로 나누고 각 메모리 영역의 변수 값을 비교함으로써 공격을 탐지하고 방어한다. 다중 ASR에서 각 데이터 메모리 영역의 변수는 서로 다른 순서로 배치되므로 한 번의 공격을 통해 동시에 동일한 변수 값을 조작하는 것은 불가능하다. 다중 ASR이 적용된 프로그램은 중복 수행으로 인해 비교적 높은 성능 부하를 보이나, 실제 공격 대상이 되는 웹서버 등 I/O 처리가 많이 요구되는 프로그램의 경우 40%~50% 정도의 성능 부하를 보인다. 아울러 본 논문에서는 프로그램에 다중 ASR을 적용하기 위한 변환프로그램을 개발하였다. ASR is an excellent program security technique that protects various data memory areas without run-time overhead. ASR hides the addresses of variables from attackers by reordering variables within a data memory area; however, it can be broken by brute force attacks because of a limited data memory space. In this paper, we propose Multiple ASR to overcome the limitation of previous ASR approaches. Multiple ASR separates a data memory area into original and duplicated areas, and compares variables in each memory area to detect an attack. In original and duplicated data memory areas variables are arranged in the opposite order. This makes it impossible to overwrite the same variables in the different data areas in a single attack. Although programs with Multiple ASR show a relatively high run-time overhead due to duplicated execution, programs with many I/O operations such as web servers, a favorite attack target, show 40~50% overhead. In this paper we develop and test a tool that transforms a program into one with Multiple ASR applied.

2단계 동적 축소법을 적용한 구조물의 위상 최적 설계

박수현,김현기,조맹효,Park Soo-Hyun,Kim Hyun-Gi,Cho Maeng-Hyo 한국전산구조공학회 2006 한국전산구조공학회논문집 Vol.19 No.2

Topology optimization problem requires numerous repeated evaluations of objective function and design sensitivity for elements within design domain with various density distributions. The recently proposed two-level condensation scheme(TLCS) is very promising for the construction of reduced system and for an accurate and efficient analysis concerned about eigenvalue and dynamic problems. We used the two-level dynamic condensation scheme for the analysis and sensitivity computation part in the structural topology optimization problem. The results of the topology optimization for the reduced system show the TLCS provides high accuracy and computation efficiency compared to the full scale system within engineering accuracy.

MANET에서의 Reactive Routing Keyword 기반 라우팅 프로시듀어

박수현,신수영,Park Soo-Hyun,Shin Soo-Young 한국시뮬레이션학회 2004 한국시뮬레이션학회 논문지 Vol.13 No.4

In MANET(Mobile Ad-hoc Network), unlike in wired networks, a path configuration should be in advance of data transmission along a routing path. Frequent movement of mobile nodes, however, makes it difficult to maintain the configured path and requires re-configuration of the path very often. It may also leads to serious problems such as deterioration of QoS in mobile ad-hoc networks. In this paper, we proposed a Reactive Routing Keyword (RRK) routing procedure to solve those problems. Firstly, we noticed it is possible in RRK routing to assign multiple routing paths to the destination node. We applied this feature into active networks and SNMP information based routing by storing unique keywords in cache of mobile nodes corresponding to present and candidate routings in a path configuration procedure. It was shown that the deterioration of QoS which may observed in Dynamic Source Routing(DSR) protocol was greatly mitigated by using the proposed routing technique.

페로니켈 슬래그를 이용(利用)한 수산화(水酸化)마그네슘 제조방법(製造方法)

박수현,추용식,송훈,이종규,서성관,Park, Soo Hyun,Chu, Yong Sik,Song, Hun,Lee, Jong Kyu,Seo, Sung Kwan 한국자원리싸이클링학회 2013 자원리싸이클링 Vol.22 No.1

Ferro-Nickel slag is a byproduct of Ferro-Nickel manufacturing process. Ferro-Nickel slag mostly discarded or used as aggregates despite having useful ingredients such as magnesium oxide and silicon oxide. This study tried to extract process for Mg ion using $H_2SO_4$ solution. And remove impurities and get high purity $Mg(OH)_2$ using NaOH. Mg ion was extracted with the Fe ion and other Ferro-Nickel slag composition by $H_2SO_4$ solution. It is important to control the pH because remove impurities and obtain high-purity $Mg(OH)_2$. The impurities were removed by precipitation of the hydroxides. After this process, we added NaOH and high-purity $Mg(OH)_2$ was obtained.

5개국 바이오헬스 산업의 기술융합과 트렌드 분석 : 특허 동시분류분석과 텍스트마이닝을 활용하여

박수현,윤영미,김호용,김재수,Park, Soo-Hyun,Yun, Young-Mi,Kim, Ho-Yong,Kim, Jae-Soo 한국융합학회 2021 한국융합학회논문지 Vol.12 No.4

The study aims to identify convergence and trends in technology-based patent data for the biohealth sector in IP5 countries (KR, EP, JP, US, CN) and present the direction of development in that industry. We used patent co-classification analysis-based network analysis and TF-IDF-based text mining as the principal methodology to understand the current state of technology convergence. As a result, the technology convergence cluster in the biohealth industry was derived in three forms: (A) Medical device for treatment, (B) Medical data processing, and (C) Medical device for biometrics. Besides, as a result of trend analysis based on technology convergence results, it is analyzed that Korea is likely to dominate the market with patents with high commercial value in the future as it is derived as a market leader in (B) medical data processing. In particular, the field is expected to require technology convergence activation policies and R&D support strategies for the technology as the possibility of medical data utilization by domestic bio-health companies expands, along with the policy conversion of the "Data 3 Act" passed by the National Assembly in January 2019.

C₁₂A₇계(系) 슬래그를 사용(使用)한 수축저감제(收縮低減劑)의 혼합재(混合材) 함량(含量)에 따른 특성(特性)

박수현,추용식,서성관,박재완,Park, Soo Hyun,Chu, Yong Sik,Seo, Sung Kwan,Park, Jae Wan 한국자원리싸이클링학회 2013 자원리싸이클링 Vol.22 No.6

In this Study, it was fabricated that shrinkage reducing agent and mortar used $C_{12}A_7$-based slag enhanced the shrinkage reduction and compressive strength. To reduce cement content, setting time, flow and compressive strength of mortar with varying content of fly ash and blast furnace slag were experimented. The flow increased and setting time delayed as the increase of fly ash and blast furnace slag content. And early strength was lower and long age strength was higher than that of mortar with low content of admixture.

Interaction between norepinephrine and angiotensin II on Na⁺ uptake in primary cultured rabbit renal proximal tubule cells

박수현,고현주,한호재,Park, Soo-hyun,Koh, Hyun-ju,Han, Ho-jae The Korean Society of Veterinary Science 1998 대한수의학회지 Vol.38 No.3

신장 근위세뇨관세포들은 사구체에서 여과된 물질의 재흡수, 분비 및 대사에 관여하는 여러 호르몬들의 수용체들을 가지고 있다. 이들중에서 norepinephrine(NE)과 angiotensin II(ANG II)는 $Na^{+}/H^+$ 상호운반계를 조절함으로써 혈압조절에 관여하는 것으로 알려져 있으나 이들의 상호관계에 대해선 연구보고가 많지 않다. 본 연구는 초대배양한 토끼신장 근위세뇨관세포를 이용한 $Na^+$ uptake 실험을 통하여 NE이 어떠한 수용체를 통하여 $Na^{+}/H^+$ 상호운반계를 조절하는지 그리고 이러한 작용에 있어서 NE과 ANG II의 상호관계를 알아보고자 실시하였다. NE(>$10^{-9}M$)은 $Na^+$ uptake를 유의성 있게 증가시켰다($10^{-9}M$ NE : $27{\pm}4%$ increase vs. Control;p < 0.05). $\alpha$ 길항제(phentolamine, $10^{-10}M$)는 NE($10^{-9}M$)에 의해 유도된 $Na^+$ uptake를 유의성 있게 차단하였으나 (phentolamine+NE : $29{\pm}5%$ inhibition vs. NE ; p〈 0.05), ${\alpha}_1$ (pra-zosin, $10^{-10}M$) 및 ${\alpha}_2$ 길항제(yohimbine, $10^{-10}M$)는 부분적으로 차단하였다. ${\beta}$ 길항제(propra-nolol, $10^{-10}M$)도 역시 NE에 의해 유도된 $Na^+$ uptake를 유의성 있게 차단하였으나(propranolol+NE : $24{\pm}6%$ inhibition vs. NE ; p< 0.05), ${\beta}_1$(atenolol, $10^{-10}M$) 및 ${\beta}_2$ 길항제(butoxamine, $10^{-10}M$)는 부분적으로 차단하였다. 이러한 결과들은 NE에 의해 유도된 $Na^+$ uptake 증가작용은 ${\alpha}$(${\alpha}_1$ 및 ${\alpha}_2$ )와 ${\beta}$(${\beta}_1$ 및 ${\beta}_2$) 수용체 모두를 통하여 일어난다는 것을 시사해주고 있다. ANG II($10^{-11}M$) 또는 NE(${\alpha}_1$, ${\alpha}_2$, ${\beta}_1$, ${\beta}_2$ 작동제) 단독처리군의 $Na^+$ uptake는 대조군에 비해 유의성 있게 증가하였으나 (ANG II : $23{\pm}9%$ increase vs. Control; p < 0.05), 병합처리시 상승작용은 나타나지 않았다. ${\alpha}$ 또는 ${\beta}$ 길항제 처리시 NE 및 ANG II에 의해 유도되었던 $Na^+$ uptake 증가는 유의성 있게 차단되었다(phentolamine+NE+ANG II : $25{\pm}3%$ inhibition, propranolol+NE+ANG II : $24{\pm}6%$ inhibition vs. NE+ANG II, respectively ; p〈 0.05). 이 결과들은 $Na^+$ uptake에 있어서 ${\alpha}$(${\alpha}_1$ 및 ${\alpha}_2$)와 ${\beta}$(${\beta}_1$ 및 ${\beta}_2$) 수용체와 ANG II의 관련성을 시사해 준다. 결론적으로 토끼 신장 근위세뇨관세포에서 NE은 ${\alpha}_1$, ${\alpha}_2$, ${\beta}_1$ 및 ${\beta}_2$ 수용체를 통하여 $Na^+$+ uptake를 증가시켰으며 이들 수용체는 ANG II $Na^+$ uptake 증가작용에 관여하였다.

산업부산물을 활용한 제철·제강용 합성 칼슘 페라이트 특성 - (1)

박수현,추용식,서성관,박재완,Park, Soo Hyun,Chu, Yong Sik,Seo, Sung Kwan,Park, Jae Wan 한국자원리싸이클링학회 2014 자원리싸이클링 Vol.23 No.5

Calcium ferrite is more effective binder for making sintered ore and flux for steel making because of it's low melting temperature. In this Study, calcium ferrite was made by calcinating method in the cement manufacturing process in order to reduce manufacturing costs and increase productivity. Limestone and calcination sludge were used as CaO source, steelmaking sludge, blast furnace dust and iron ore were used as Fe-bearing raw materials. The sintering temperature of specimens is in the range of $950{\sim}1170^{\circ}C$. For Calcium ferrite can be used 'binder for making sintered ore' or 'flux for converter/electric furnace' with a low melting point properties, the raw material characteristics and sintering properties were investigated.

무수석고와 C₁₂A₇계 슬래그를 사용한 수축저감제 및 모르타르 특성

박수현,추용식,서성관,박재완,Park, Soo-Hyun,Chu, Yong-Sik,Seo, Sung-Kwan,Park, Jae-Wan 한국건설순환자원학회 2013 한국건설순환자원학회 논문집 Vol.1 No.2

In this study, shrinkage reducing agent was fabricated with $12CaO{\cdot}7Al_2O_3(C_{12}A_7)$ of CA-based slag and anhydrite. Mortars added shrinkage reducing agent were experimented for enhancement of shrinkage reduction and compressive strength. The properties of setting time, length change and compressive strength of mortar changed with mixing ratios. From 0% to 6% $C_{12}A_7$-based slag, setting times got shorter and length changes of mortars were similar to 7days. From 1day to 7days, the more mortar had $C_{12}A_7$-based slag, the higher compressive strength. At 28days, compressive strength of mortars with 6% $C_{12}A_7$-based slag was about 36MPa. After 35days, mortar with 6% $C_{12}A_7$-based slag had the lowest ratio of shrinkage reduction. So mortar with 6% $C_{12}A_7$-based slag had the excellent characteristics such as compressive strength and shrinkage reduction ratio. 본 연구에서는 CA계 슬래그와 무수석고를 사용하여 수축저감제를 제조하였으며, 모르타르의 압축강도와 건조수축 특성을 향상시키기 위해서 상기 수축저감제를 첨가하였다. 모르타르의 응결시간, 길이변화율 및 압축강도는 수축저감제의 배합비율에 따라 변화하였다. 슬래그가 0~7%까지 첨가된 모르타르는 슬래그 첨가량 증가에 따라 응결시간이 짧아졌으며, 7일까지의 길이변화율은 유사하였다. 7일 양생조건의 압축강도는 $C_{12}A_7$계 슬래그 첨가량 증가에 따라 증가되었다. $C_{12}A_7$계 슬래그가 6% 첨가된 모르타르의 28일 강도는 약 36 MPa이었으며, 35일에서의 건조수축율은 가장 낮은 값을 나타내었다. 그러므로 $C_{12}A_7$계 슬래그가 6% 첨가된 모르타르에서 우수한 물리적 특성을 발현하는 것으로 판단할 수 있었다.