랫드에서 Perfluorooctanoic Acid의 독성에 관한 연구

김용훈,조은상,김아영,김성환,박민식,조성환,류시윤,정주영,손화영,Kim, Yong-Hoon,Cho, Eun-Sang,Kim, A-Young,Kim, Sung-Hwan,Park, Min-Sik,Cho, Sung-Whan,Ryu, Si-Yun,Jung, Joo-Young,Son, Hwa-Young 대한수의학회 2008 大韓獸醫學會誌 Vol.48 No.3

Perfluorooctanoic acid (PFOA), a member of the perfluoroalkyl acids that have wide commercial applications, is persistent organic pollutants widely spread throughout the environment and human population. But little is known about the adverse biological effects of the PFOA. In the present study, the toxicological effects of PFOA were investigated in rats. Sprague-Dawley rats (N = 10 in each group) were orally administered with PFOA in drinking water for 4 weeks (0, 100, 200, or 400 ppm in male, and 0, 200, 400, or 800 ppm in female). Three female rats given 800 ppm died during the study. PFOA treatment decreased the body weight gain and increased the liver weights in both genders. Serum biochemical investigations revealed significant increases in the aspartate aminotransferase, alanine transaminase, alkaline phosphatase, blood urea nitrogen, total cholesterol, and total bilirubin in male but in female. Serum estradiol (E2) levels were increased in all treated rats. Histopathologically, hepatocellular hypertrophy around central vein was noted in the liver of treated rats. No significant histopathological changes were noted in other organs. In conclusion, PFOA induced toxicological changes in the liver and increased serum E2 level which was not related to histopathological changes of endocrine and reproductive system.

동행$365^+$ - 국외출장보고서 - 돼지이력제 해외사례조사

김용훈,양대용,Kim, Yong-Hun,Yang, Dae-Yong 축산물품질평가원 2012 KAPE누리 Vol.187 No.-

SGML 문서 관리 시스템의 설계 및 구현

김용훈,이원석,류은숙,이규철,이상기,김현기,이혜란,주종철,Kim Yong-Hun,Lee Won-Suk,Ryu Eun-Suk,Lee Kyu-Chul,Lee Sang-Ki,Kim Hyun-Ki,Lee Hae-Ran,Zhoo Zong-Chul 한국문헌정보학회 1998 한국문헌정보학회지 Vol.32 No.3

다가오는 21세기는 고도화된 정보화 사회가 될 것이며, 이러한 정보화 사회에서 필수적인 요소로는 기하급수적으로 발생되는 전자 문서를 관리하는 것이라 할 수 있다. 특히, 디지털 도서관(Digital Library), 인트라넷 상에서의 CSCW(Computer-Supported Cooperative Work) , CALS(Commerce At the Light Speed) 등의 최근의 응용에서는 대량의 전자 문서를 효율적으로 저장하고 관리하는 시스템이 요구되고 있다. 다양한 전자 문서의 형태 중 ISO에서 문서 교환 표준으로 제정한 SGML은 구조 정보로 사용할 수 있는 마크업(Markup)을 포함하고 있어, 문서를 구조 단위로 표현할 수 있다. 이는 대량의 전자 문서를 저장하거나 관리하는데 적합하다. 본 논문에서는 SGML 문서를 효율적으로 관리하기 위한 SGML 문서의 데이터 모델을 제시하고, 다양한 구조의 SGML 문서에 대한 스키마 동적 생성 기능과 SGML 인스턴스 저장 기능 그리고 저장된 SGML 인스턴스를 문서 혹은 문서의 구조 단위로 꺼내오는 기능을 제공하는 SGML 문서 관리 시스템을 설계하고 구현하였다. The 21st century will be the advanced Information society era. The management of very large quantity of electronic documents is important because new applications such as Digital Libraries, CSCW (Computer-Supported Cooperative Work) in Intranet, CALS (Commerce At the Light Speed) are emerging, which require the functionalities of efficient storing, searching and managing a bulk of electronic documents. SGML(Standard Generalized Markup Language) is an ISO Standard for representing structure information of electronic documents. This paper proposes an effective data model for storing and managing SGML documents. We also describe the design and implementation details of SGML document management system, which has capabilities of storing SGML instances, generating schema dynamically, and retrieving structure elements efficiently.

웨이퍼 표면의 Si₃N₄ 파티클 제거를 위한 초임계 이산화탄소 세정

김용훈,최해원,강기문,안톤커랴킨,임권택,Kim, Yong Hun,Choi, Hae Won,Kang, Ki Moon,Karakin, Anton,Lim, Kwon Teak 한국청정기술학회 2018 청정기술 Vol.24 No.3

본 연구에서는 초임계 이산화탄소와 공용매 첨가물을 이용하여 실리콘 웨이퍼 표면의 $Si_3N_4$ 파티클을 제거하는 기술을 조사하였다. 우선, 몇 가지 계면활성제와 첨가제에 관한 초임계 이산화탄소 용해도 및 파티클 분산성 평가를 통하여 초임계 공정에 대한 적합성을 확인하였다. 다양한 변수를 조정하여 파티클 세정 실험을 진행하여 최적의 제거 조건을 확립하였다. 실험에 사용된 계면활성제는 파티클 제거 효과가 떨어졌으며, 실험 후 이차 오염물이 형성됨을 확인하였다. 반면 trimethyl phosphate는 IPA공용매와 미량의 HF와 혼합된 세정 첨가제로서 초임계 이산화탄소에 5 wt%로 포함한 유체로 온도 $50^{\circ}C$, 압력 2000 psi에서 $15mL\;min^{-1}$의 유속으로 4분 간 세정한 결과, 85%의 파티클 제거 효율을 나타내었다. In this study, the removal of $Si_3N_4$ particles from the surface of a silicon wafer was investigated by using supercritical carbon dioxide, the IPA co-solvent and cleaning additive chemicals. First, the solubility of several surfactants and binders in supercritical carbon dioxide solubility and particle dispersibility in the binders were evaluated in order to confirm their suitability for the supercritical cleaning process. Particle removal experiments were carried out with adjusting various process parameters and reaction conditions. The surfactants used in the experiment showed little particle removal effect, producing secondary contamination on the surface of wafers. On the other hand, 5 wt% (with respect to $scCO_2$) of the cleaning additive mixture of trimethyl phosphate, IPA, and trace HF resulted in 85% of particle removal efficiency after $scCO_2$ flowing for 4 minutes at $50^{\circ}C$, 2000 psi, and the flow rate of $15mL\;min^{-1}$.

엄지발가락벌림을 강조한 PNF 다리패턴 시 엄지발가락벌림근을 활성화시킬 수 있는 가장 효과적인 방법은?

김용훈,박두진,Kim, Yong-Hun,Park, Du-Jin 대한고유수용성신경근촉진법학회 2020 PNF and Movement Vol.18 No.1

Purpose: This study aimed to determine the most effective way to facilitate the abductor hallucis muscle during PNF leg pattern-emphasized hallux abduction. Methods: The study recruited 18 healthy adults. All participants agreed voluntarily to take part in the study following an explanations of its purpose and procedures. They randomly performed the PNF leg pattern-emphasized hallux abduction variations in a hook-lying or sitting position. Activation of the abductor hallucis (AbH), adductor hallucis (AdH), extensor hallucis longus (EHL), and tibialis anterior (TA) muscles, and the ratio of AbH/AdH, were measured during PNF exercises using electromyography. One-way repeated ANOVA was used to compare the activation of foot intrinsic and extrinsic muscles during the four PNF exercises. Results: PNF leg pattern-emphasized hallux abduction using normal timing was significantly higher in TA compared to PNF leg pattern-emphasized hallux abduction using timing for emphasis, regardless of the starting position. The PNF leg pattern-emphasized hallux abduction using timing for emphasis in the hook-lying position was significantly higher in AbH than in other exercises. Although there was no statistically significant difference in the ratio of AbH/AdH, it was higher in the hook-lying position. Conclusion: PNF leg pattern-emphasized hallux abduction using timing for emphasis in the hook-lying position can be recommended as a method to optimize the activation of AbH and the ratio of AbH/AdH.

경제위기 대응을 위한 국가재정 건전성 유지 발전을 위한 연구

김용훈,Kim, Young-Hu 한국디지털정책학회 2014 디지털융복합연구 Vol.12 No.1

Recently economic crisis has brought world economic instability. Each country in order to stabilize the economy, fiscal rules are introduced or reinforced. Fiscal Policy in a country plays an important role in determining the economic situation in the present and future. Existing fiscal rules tend to place a rigid limit not only on the deficit ratio and thus on the scope for fiscal stabilization, but also on the extent to which fiscal policy can be used for structural purposes. But the fiscal rules are operated in many ways and adopted in various forms, with different binding of each other, according to their own fiscal situations, and political circumstances. This study shows several important factors for successful National fiscal system and continuous fiscal soundness and development. 최근 경제위기가 세계경제의 불안정을 가져왔다. 각 국가는 경기안정을 위해 재정준칙을 도입하거나 강화하고 있다. 국가재정정책은 현재와 미래의 경제상황을 결정하는 중요한 역할을 한다. 기존 회계규칙을 엄격히 제한한 재정준칙은 재정적자를 극복하고 재정안정화 범위를 확대하여 재정구조를 위한 재정정책으로 사용할 수 있다. 그러나 재정준칙은 자신의 재정상황, 정치적 상황에 따라 다양한 형태와 방법으로 운영되고 있다. 본 연구는 성공적인 국가재정시스템 및 지속적인 재정건전성과 발전에 대한 주요 요소를 제시하였다.

무지 외반증에서 Mitchell 절골술과 중족골 근위 dome 절골술의 결과 비교

김용훈,김근우,민학진,윤의성,이장호,Kim, Yong-Hoon,Kim, Keun-Woo,Min, Hak-Jin,Yoon, Eui-Sung,Lee, Jang-Ho 대한족부족관절학회 2001 대한족부족관절학회지 Vol.5 No.2

Purpose: To evaluate the clinical results of Mitchell osteotomy and proximal metatarsal dome osteotomy in hallux valgus deformity. Materials and Methods: From January 1993 to June 2000, 28 cases (17 patients) with hallux valgus deformity who underwent Mitchell osteotomy were categorized as group I, 26 cases (16 patients) who underwent proximal metatarsal dome osteotomy were categorized as group II. We analyzed clinical results according to preoperative and postoperative clinical functional analysis and objective comparison of correction angle between two groups. Results: The average hallux valgus correction in the Mitchell osteotomy group went from $36^{\circ}$ to $11^{\circ}$, and in the proximal metatarsal dome osteotomy group, the hallux valgus angle was reduced from $32^{\circ}$ to $6^{\circ}$. The intermetatarsal angle in the Mitchell osteotomy group was corrected from $13^{\circ}$ to $9^{\circ}$, and in the proximal metatarsal dome osteotomy group the intermetatarsal angle was reduced from $14^{\circ}$ to $7^{\circ}$. Although, proximal metatarsal dome osteotomy group have shown better correction angle and radiographic results in the correction of hallux valgus angle and intermetatarsal angle but, all patients in the Mitchell osteotomy and proximal metatarsal dome osteotomy groups had no statistically significant differences of clinical functional results between two groups. Conclusion: In our studies, the proximal metatarsal dome osteotomy applied to. hallux valgus deformity was found as a good radiographic results than Mitchell osteotomy, but there were no differences between the two operations in terms of functional satisfaction.

고관절에 적용한 PNF 안정화 기법과 교각운동이 요부안정화 근육에 미치는 영향

김용훈,정주현,Kim, Yong-Hun,Jung, Ju-Hyeon 대한고유수용성신경근촉진법학회 2017 PNF and Movement Vol.15 No.1

Purpose: The purpose of this study was to examine the effects of the PNF stabilization technique for the hip joint and the bridging exercise on the trunk stabilizer muscles in healthy adults. Methods: Twenty-eight healthy adults were randomly allocated to either a PNF stabilization exercise group (n = 12) or a bridging exercise group (n = 16). The outcome measures included the contraction thickness ratio in the transversus abdominis (TrA), internal oblique (IO), and external oblique (EO), and the TrA lateral slide was assessed during the abdominal drawing-in maneuver using b-mode ultrasound. The researcher measured the abdominal muscle thickness of each participant before the therapist began the intervention and at the moment that the intervention was applied. Between-group comparisons were performed using the Mann-Whitney U test. The level of statistical significance was set at 0.05. Results: The PNF intervention program showed a significant increase in the trunk stabilizer muscle. The percentage of change in the TrA thickness showed a significant interaction between intervention. However, there were no significant differences in the IO and EO between the two groups. Conclusion: The PNF stabilization technique for the hip joint can be used effectively to improve the IO and TrA muscles in healthy adults.

더블 PI:PCBM 유전체 층 기반의 초 저전력 CNT 시냅틱 트랜지스터

김용훈,조병진,Kim, Yonghun,Cho, Byungjin 한국재료학회 2017 한국재료학회지 Vol.27 No.11

We demonstrated a CNT synaptic transistor by integrating 6,6-phenyl-C61 butyric acid methyl ester(PCBM) molecules as charge storage molecules in a polyimide(PI) dielectric layer with carbon nanotubes(CNTs) for the transistor channel. Specifically, we fabricated and compared three different kinds of CNT-based synaptic transistors: a control device with $Al_2O_3/PI$, a single PCBM device with $Al_2O_3/PI:PCBM$(0.1 wt%), and a double PCBM device with $Al_2O_3/PI:PCBM$(0.1 wt%)/PI:PCBM(0.05 wt%). Statistically, essential device parameters such as Off and On currents, On/Off ratio, device yield, and long-term retention stability for the three kinds of transistor devices were extracted and compared. Notably, the double PCBM device exhibited the most excellent memory transistor behavior. Pulse response properties with postsynaptic dynamic current were also evaluated. Among all of the testing devices, double PCBM device consumed such low power for stand-by and its peak current ratio was so large that the postsynaptic current was also reliably and repeatedly generated. Postsynaptic hole currents through the CNT channel can be generated by electrons trapped in the PCBM molecules and last for a relatively short time(~ hundreds of msec). Under one certain testing configuration, the electrons trapped in the PCBM can also be preserved in a nonvolatile manner for a long-term period. Its integrated platform with extremely low stand-by power should pave a promising road toward next-generation neuromorphic systems, which would emulate the brain power of 20 W.

혼합현실기반 이러닝 기술동향

김용훈,이수웅,이준석,노경희,Kim, Y.H.,Lee, S.W.,Lee, J.S.,Noh, K.H. 한국전자통신연구원 2009 전자통신동향분석 Vol.24 No.1

메인프레임 기반 컴퓨팅에서 PC 기반 컴퓨팅에 이어 제3세대 컴퓨터 환경인 유비쿼터스 컴퓨팅 환경으로의 진화는 현실에 컴퓨터를 탑재하여 언제 어디서나 모든 곳에 존재하는 네트워크 환경을 제공하고 있고, 이러한 유비쿼터스 컴퓨팅과 이를 연동한 네트워크 패러다임은 미래교육 시스템이 나가야 할 새로운 방향을 제시한다. 양방향 의사소통을 기본으로 하는 지식기반사회의 교육패러다임의 변화는 컴퓨터의 역할 패러다임의 변화와 그 맥을 함께 하고 있으며, 이러닝 분야에서도 기존의 단순하고 일방향적인 교육 콘텐츠에서 벗어나 새로운 기술에 기반한 고품질의 양방향적 콘텐츠를 요구하고 있다. 이에 대한 하나의 대안으로 학습자에게 실재감과 몰입감을 촉진하고 마커의 직접적인 조작활동을 통해 양방향 상호작용을 극대화 할 수 있는 혼합현실(mixed reality) 기반 이러닝 시스템의 개발이 시도되고 있다. 본 고에서는 이러한 혼합현실기반 이러닝 기술의 동향에 대해 살펴보고자 한다.