질소 가스 내에서의 전자 수송계수에 대한 몬테칼로 해석

심재학,정운관 조선대학교 에너지.자원신기술연구소 2003 에너지·자원신기술연구소 논문지 Vol.25 No.1

In this paper, electron swarm parameter is calculated by Monte-Carlo method in nitrogen gas. Under the uniform electric field, the motion of electron which depends on the electric field is calculated by time of flight(TOF) method, and the type of collision between electron and nitrogen molecule are determined by the comparison between collision cross section of nitrogen gas and random number. On the assumption that nitrogen pressure is 200[Torr] and 50≤E/p≤700[Vcm^(-1)Torr^(-1)], we calculate the ionization coefficients, drift velocity, energy distribution and diffusion phenomena, and compare these values with experimental values.

종골 골절 치료에 있어서의 전산화 단층 촬영의 유용성

김학준,하권익,윤정로,심재익,김택선,김영배,이우승,최재혁 대한골절학회 2003 대한골절학회지 Vol.16 No.4

NMR에 依한 trans-2-Butene-dial dioxime의 立體構造에 關한 硏究

李學沂,沈相喆,嚴在國 慶北大學校 1976 論文集 Vol.21 No.-

The structure of trans-2-butene-dial dioxime was investigated by means of NMR spectroscopy. Its conformer was found to have the planar structure conjugated with the double-bonds from the vicinal spin-spin coupling constants. The configurations of two oxime group were investigated from the solvent effects and assigned as the perfect symmetric structures, mixture of "syn-syn" and "anti-anti" forms.

신경회로망을 이용한 이면비드 폭 예측에 관한 연구

정재원,김일수,박창언,김학형,서주환,김인주,심지연 한국공작기계학회 2008 한국공작기계학회 춘계학술대회논문집 Vol.2008 No.-

The development of robotic welding process is a very complex assignment because the system is affected by a number of process parameters which are very difficult to determine or predict in practice. The full automation welding has not yet been achieved partly because the mathematical model for the process parameters of a given welding task is not fully understood and quantified. Several mathematical models to control welding quality, Productivity, micro structure and weld properties in arc welding processed have been studied. However, it is not an easy task to apply them to the various practical situations because the relationship between the process parameters and the bead geometry is non-linear and also they are usually dependent on specific experimental result. Practically, it is difficult, but important to know how to establish a mathematical model that can predict the result of the actual welding process and how to select the optimum welding condition under a certain constraint. In this paper, an attempt has been made to develop an neural network model to predict the back-bead width as a function of key process parameters in the GMA (Gas Metal Arc) welding and to compare the developed models with the experimental results

개인피폭선량 알고리즘의 평가

정운관,심재학,김영진 조선대학교 에너지.자원신기술연구소 2004 에너지·자원신기술연구소 논문지 Vol.26 No.2

This paper describes experimental evaluation of exposure dose algorithm for film badge and the results of the personnel dosimetry performance test. Reference radiations irradiate seven categories, except the neutron category prescribed in the ANSI N13.11-1993. The performance criterion in a given category, sum of the absolute value of the bias and the standard deviation of the performance quotient, was estimated by the use of film badge algorithm and dose equivalents according to the standard method. As a result, the performance index in a given category showed a good agreement less than tolerance level, for the deep and shallow dose equivalents or absorbed dose, and this study is satisfied with quality decision cnterion of the film badge personnel dosimeter and intercomparison results.

슬관절 내측부 인대 손상의 보존적 치료

임홍철,심재학,남혁우,왕준호,노영진 대한스포츠의학회 2000 대한스포츠의학회지 Vol.18 No.2

Purpose : The medial collateral ligament injury is the most common injury of the knee. Recently Non-operative treatment has been preferred than operative treatment and most of patients have satisfactory clinical results after non-operative treatment. But a few patients have continuous instability after non-operative treatment, so the purpose of this study is to fine out the cause of persistent symptom. Methods and Materlals : We performed a retrospective study of one hundred thirty seven patients with medial collateral ligament injury treated non-operative from January 1990 to December 1997. W divided patients into two groups: isolated medial collateral ligament injury (groupⅠ): medial collateral ligament injury with concomitant anterior cruciate ligament injury (groupⅡ) and we analysed MRI finding, valgus instability, and Lysholm knee score. Result : At the follow up, three of group Ⅰ, five of group Ⅱ had persistent grade Ⅲ valgus instability. In group Ⅰ, we could find two case of rupture of the proper of medial collateral ligament with inward inversion and one case of concomitant posteromedial compartment injury. We could find the proper rupture of medial collateral ligament with inversion inward in two patients, the injury of posteromedial compartment in one patient. Two patients of group Ⅱ with grade Ⅲ valgus instability had anterior instability with laxity of grafted tendon after anterior cruciate ligament reconstruction. Conclusion : Most of isolated injury of the medial collateral ligament heals wthout operative intervention. But in case of rupture of the proper portion of medial collateral ligament with inversion inward or concomitant injury of posteromedial compartment, we should consider the operative treatment of medial collateral ligament. In case of medial collateral ligament injury with anterior cruciate ligament, it would better to consider the delicate reconstruction of anterior cruciate ligament.

Shp2 is Involved in Neuronal Differentiation of Hippocampal Precursor Cells

Hak-Jae Kim,Ah Mi Han,Jae Hwan Shim,Hye Hyun Yoon,권혁만,Yunhee Kim Kwon 대한약학회 2007 Archives of Pharmacal Research Vol.30 No.6

HiB5 is a multipotent hippocampal stem cell line whose differentiation into cells of a neuronal phenotype is promoted by neurotrophic factors such as PDGF and brain-derived neurotrophic factor (BDNF). We examined the potential role of Src homology 2 (SH2)-containing protein tyrosine phosphatase (Shp2) in this differentiation process. We found that Shp2 became tyrosine phosphorylated following PDGF treatment. Wild-type Shp2 enhanced the expression of neurofilament, synapsin I and PSD95 by PDGF and BDNF, whereas their expression was attenuated by the catalytically inactive mutants Shp2C/S and Shp2∆P. Formation of dendritic spine-like structures increased with wild-type Shp2, but diminished with Shp2C/S and Shp2∆P. PSD95, localized in the post-synaptic density region of dendritic spines, PDGFRβ and TrkB were co-immunoprecipitated with Shp2 antibodies. These results suggest that Shp2 plays a positive role in mediating PDGF- and BDNF-activated signaling which promotes the formation of dendritic spines.

DISASTER IMPACT ASSESSMENT PROGRAM FOR SUSTAINABLE DEVELOPMENT IN KOREA

SHIM JAE-HYUN,KIM JI-TAE,CHUNG JAE-HAK,KIM JIN-YOUNG 한국수자원학회 2005 한국수자원학회 학술대회 Vol.2005 No.1

Facile production of biofuel via solvent-free deoxygenation of oleic acid using a CoMo catalyst

Shim, Jae-Oh,Jeon, Kyung-Won,Jang, Won-Jun,Na, Hyun-Suk,Cho, Jae-Wan,Kim, Hak-Min,Lee, Yeol-Lim,Jeong, Dae-Woon,Roh, Hyun-Seog,Ko, Chang Hyun Elsevier 2018 Applied Catalysis B Vol.239 No.-

<P><B>Abstract</B></P> <P>Support- and sulfide-free cobalt molybdenum catalysts are prepared via different synthetic procedures for catalytic deoxygenation of oleic acid under inert (N<SUB>2</SUB>) and solvent-free conditions. Among the tested catalysts, the CoMo catalyst prepared via a sol-gel method achieves the highest catalytic performance, namely, 88.9% oleic acid conversion, with 48.1% C<SUB>9</SUB>–C<SUB>17</SUB> selectivity, and 69.6% oxygen removal rate, owing to its excellent physical properties. Additionally, oxygen vacancy is formed in CoMo catalyst during sol-gel synthesis process and it also effect on the catalytic activity. Examination of the deoxygenation reaction over pre-reduced catalysts reveals that the CoMoO<SUB>4</SUB> species is the active species in the CoMo catalysts. The fuel properties of the resultant products are affected strongly by the catalytic performances of the CoMo catalysts. The biofuel produced using the CoMo catalyst prepared via the sol-gel method showed the highest calorific value (10,119 cal/g) and the lowest viscosity (31.5 cP), and, consequently, this CoMo catalyst exhibits the highest catalytic activity and has significant potential for application in biofuel production.</P> <P><B>Highlights</B></P> <P> <UL> <LI> This study describes an efficient and accessible method for biofuel production. </LI> <LI> Deoxygenation of oleic was carried out under inert, solvent-free conditions. </LI> <LI> CoMo catalysts are prepared via different synthetic procedures. </LI> <LI> CoMo catalyst prepared via sol-gel method showed the highest catalytic performance. </LI> <LI> It also exhibits calorific value that is very similar to that of commercial diesel. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Boronic acid-tethered amphiphilic hyaluronic acid derivative-based nanoassemblies for tumor targeting and penetration

Jeong, Jae Young,Hong, Eun-Hye,Lee, Song Yi,Lee, Jae-Young,Song, Jae-Hyoung,Ko, Seung-Hak,Shim, Jae-Seong,Choe, Sunghwa,Kim, Dae-Duk,Ko, Hyun-Jeong,Cho, Hyun-Jong Elsevier Science B.V. Amsterdam 2017 ACTA BIOMATERIALIA Vol. No.

<P><B>Abstract</B></P> <P>(3-Aminomethylphenyl)boronic acid (AMPB)-installed hyaluronic acid–ceramide (HACE)-based nanoparticles (NPs), including manassantin B (MB), were fabricated for tumor-targeted delivery. The amine group of AMPB was conjugated to the carboxylic acid group of hyaluronic acid (HA) <I>via</I> amide bond formation, and synthesis was confirmed by spectroscopic methods. HACE-AMPB/MB NPs with a 239-nm mean diameter, narrow size distribution, negative zeta potential, and >90% drug encapsulation efficiency were fabricated. Exposed AMPB in the outer surface of HACE-AMPB NPs (in the aqueous environment) may react with sialic acid of cancer cells. The improved cellular accumulation efficiency, <I>in vitro</I> antitumor efficacy, and tumor penetration efficiency of HACE-AMPB/MB NPs, compared with HACE/MB NPs, in MDA-MB-231 cells (CD44 receptor-positive human breast adenocarcinoma cells) may be based on the CD44 receptor-mediated endocytosis and phenylboronic acid-sialic acid interaction. Enhanced <I>in vivo</I> tumor targetability, infiltration efficiency, and antitumor efficacies of HACE-AMPB NPs, compared with HACE NPs, were observed in a MDA-MB-231 tumor-xenografted mouse model. In addition to passive tumor targeting (based on an enhanced permeability and retention effect) and active tumor targeting (interaction between HA and CD44 receptor), the phenylboronic acid-sialic acid interaction can play important roles in augmented tumor targeting and penetration of HACE-AMPB NPs.</P> <P><B>Statement of Significance</B></P> <P>(3-Aminomethylphenyl)boronic acid (AMPB)-tethered hyaluronic acid-ceramide (HACE)-based nanoparticles (NPs), including manassantin B (MB), were fabricated and their tumor targeting and penetration efficiencies were assessed in MDA-MB-231 (CD44 receptor-positive human adenocarcinoma) tumor models. MB, which exhibited antitumor efficacies <I>via</I> the inhibition of angiogenesis and hypoxia inducible factor (HIF)-1, was entrapped in HACE-AMPB NPs in this study. Phenylboronic acid located in the outer surface of HACE-AMPB/MB NPs (in the aqueous <I>milieu</I>) may react with the sialic acid over-expressed in cancer cells and intramolecular B‒O bond can be formed. This phenylboronic acid-sialic acid interaction may provide additional tumor targeting and penetration potentials together with an enhanced permeability and retention (EPR) effect (passive tumor targeting) and HA-CD44 receptor interaction (active tumor targeting). Developed HACE-AMPB NP may be one of promising nanocarriers for the imaging and therapy of CD44 receptor-expressed cancers.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>