• Bulletin of the Korean Chemical Society
• /
• v.24 no.11
• /
• pp.1671-1674
• /
• 2003

The effects of amine donors ($a:NH_2,\;b:NMe_2,\;c:NMePh,\;d:NPh_2$) and conjugation length on the molecular hyperpolarizabilities of a series of dipolar molecules have been theoretically investigated by using CPHF/6-31G method. The first hyperpolarizabilities (${\beta}$) of p-nitrobenzene derivatives increase with the donor in the order, $NH_2\;<\;NMe_2\;<\;NMePh\;<\;NPh_2$, whereas slightly different order is observed in more conjugated derivatives, i.e., $NH_2\;<\;NPh_2\;<\;NMe_2\;<\;NMePh$. The result has been attributed to the extent of charge transfer and torsion angle. Moreover, the results show that "non-traditional" ${\pi}$-conjugation effect exists in small compounds and decreases as the conjugation length between donor and acceptor increases.

• Proceedings of the KIEE Conference
• /
• 2002.06a
• /
• pp.94-97
• /
• 2002

CdS and $CdS:Co^{2+}$ single crystals were grown by CTR method using iodine as transport material. The grown single crystals have defect chalcopyrite structure with direct band gap. The optical energy band gap was decreased according to add of Co-impurity. We can observed the Co-impurity optical absorption peaks assigned to the $Co^{2+}$ ion sited at the $T_d$ symmetry lattice and we consider that they were attributed to the electron transitions between energy levels of ions.

• Proceedings of the KIEE Conference
• /
• 2003.07b
• /
• pp.1102-1104
• /
• 2003

The human beings have increased concern about energy saving and alternative energy. The Power demand has increased the growth of industry and the improvement of lift. We have to explore alternate energy sources and utilize effectively domestic resources. The lighting equipments developed energy saving by using an electric ballast. The load installation should be promoted to rational power management according to the network, intelligent and high-function. Therefore, this paper has studied the method of energy saving and consulting.

• Proceedings of the KIEE Conference
• /
• 2003.07c
• /
• pp.1785-1787
• /
• 2003

본 논문에서는 현재 대용량 전력변환 소자인 사이리스터는 해남-제주간의 HVDC변환소에 채용되어 운전중에 있고, BTB 및 SVC등에 채용되고 있으며, 향후 FACTS, 남북 전력계통연계, 동북아 계통연계 등 전력변환용으로 사용될 부품으로 사용범위가 날로 증가하고 있는 2,208개의 사이리스터의 수명 및 신뢰성을 평가하기 위해 고온직류 blocking 가속열화시험조건에 대해서 기술하였다.

• Proceedings of the KIEE Conference
• /
• 1996.07b
• /
• pp.990-992
• /
• 1996

The design of I/O scaling factors for fuzzy controller system is proposed in this paper. The proposed method is for nonlinear input scaling factor and variable output scaling factor. The fuzzy controller is evaluated by computer simulation on the 1st order process and 2nd order process. Simulation results showed robust characteristics for variable reference signal.

• Journal of the military operations research society of Korea
• /
• v.27 no.2
• /
• pp.134-148
• /
• 2001

In this paper, air-defense simulation model, called "DADSim", will be introduced. DADSim(Distributed Air Defense Simulation Model) was developed by Modeling&Simulation Lab of K.N.D.U.(Korea National Defence Univ) Weapon Systems Department. This model is an analysis-purpose model in the engagement-level. DADSim can simulate not only the global air-defense or Korean Peninsula but also the local air-defense or a battle field. DADSim uses the DTED(digital terrain elevation data) LeveII it for the representation of peninsula terrain characteristics. The weapon systems cooperated in the model are low/medium-range missile systems such as HAWK, NIKE, SAM. DADSim was designed in the way of object-oriented development method, implemented by C++ language. The simulation view is an event-sequenced object-orientation. For the convenience of input, output analysis, GUI(Graphic User Interface) of menu, window, dialog box, etc. are provided to the user, For the execution of DADSim, Silicon Graphic IRIX 6.3 or high version is required. DADSim can be used for the effectiveness analysis of­defence systems. Some illustrative examples will be shown in this paper.

• Journal of Electrochemical Science and Technology
• /
• v.9 no.4
• /
• pp.292-300
• /
• 2018

The electrocatalytic oxidative behavior of an antiarrhythmic drug, procainamide hydrochloride (PAH) at the gold electrode surface has been examined using different voltammetric methods like cyclic, linear-sweep and differential pulse voltammetry. Voltammograms obtained in this study reveal that the electrode exhibit excellent electrocatalytic activity towards oxidation of the drug. The parameters that can affect the peak current at different pH, scan rate and concentration were evaluated. The number of electrons transferred was calculated. The current displayed a wide linear response ranging from 0.5 to $30.0{\mu}M$ with a limit of detection of 56.4 nM. The impact of potential interfering agents was also studied. The electrode displayed wide advantages such as simple sample preparation, appreciable repeatability, reproducibility and also high sensitivity. Furthermore, the feasibility of the proposed method was successfully demonstrated by determining PAH in the spiked human biological sample.

• Journal of the Korean Society for Precision Engineering
• /
• v.14 no.5
• /
• pp.100-107
• /
• 1997

A pneumatic artificial muscle type of actuator, which acts similar to human muscle, is developed recently. In this paper, an adaptive controller is presented for the trajectory tracking problem of a two-degree- of-freedom manipulator using two pairs of pneumatic artificial muscle actuators. Due to the nonlinearity and the uncertainty on the dynamics of the actuator, it is difficult to make the effective control schemes of this system. By the adaptive control law which inclueds a nonlinear "feedforward" term compensating paramet- ric uncertainties in addition to P.I.D. scheme, both golbal stability of the system and convergence of the tracking error are guaranted. The effectiveness of the proposed control method for the manipulator using this actuator is illustrated through experiments.periments.

• Journal of Nutrition and Health
• /
• v.44 no.6
• /
• pp.481-487
• /
• 2011

Obesity not only reduces bone mineral density but also increases inflammatory markers. Therefore, we examined the change in inflammatory markers and morphological microstructure of the bones using a mouse model fed a high-fat diet. C57BL/6J 4-week-old male mice were divided into a control group (n = 6) and a experimental group (n = 6); the control group was provided with 10% Kcal fat diet, and the high-fat diet group was provided with 45% Kcal fat diet for 12 weeks using the free provision method. Blood was analyzed for inflammatory markers, and micro-computed tomography was used to measure the morphological microstructure of the femoral bone. The weight increases in the control group and high-fat diet group were $5.85{\pm}1.84g$ and $16.06{\pm}5.64g$, respectively (p < 0.01), glucose was $115.00{\pm}16.88mg/dL$ and $188.33{\pm}13.29mg/dL$ (p < 0.01), and triglycerides were $65.00{\pm}6.19mg/dL$ and $103.33{\pm}8.02mg/dL$ (p < 0.05) respectively. Leptin and interleukin (IL)-6 were significantly higher in the high-fat diet group than that in the control group (p < 0.01). As a result of a biochemical index analysis of bone metabolism, osteocalcin tended to be lower in the high-fat diet group, whereas CTx was significantly higher in the high-fat diet group compared to that in the control group (p < 0.01). The thickness of the bony trabecula was significantly narrower in the high-fat diet group than that in the control group (p < 0.05), and the gap in the bony trabecula was significantly wider in the high-fat diet group than that in the control group (p < 0.05). IL-6 and the gap in the bone trabecula, which was a morphological microstructure of the bones, showed a positive correlation (p < 0.05). Taken together, inducing obesity through a high-fat diet in mice during the growth phase caused a change in bone microstructure and was correlated with the inflammation index. Accordingly, restriction of excessive fat intake may be needed to suppress the inflammatory reactions and promote normal bone formation.

• Korean Journal of Materials Research
• /
• v.13 no.8
• /
• pp.519-523
• /
• 2003

We report the synthesis of cubic spinel $ZnCo_2$$O_4$thin films and the tunability of the conduction type by control of the oxygen partial pressure ratio. Zinc cobalt oxide films were grown on$ SiO_2$(200 nm)/Si substrates by reactive magnetron sputtering method using Zn and Co metal targets in a mixed Ar/$O_2$atmosphere. We found from X-ray diffraction measurements that the crystal structure of the zinc cobalt oxide films grown under an oxygen-rich condition (the $O_2$/Ar partial pressure ratio of 9/1) changes from wurtzite-type $Zn_{1-x}$ $Co_{X}$O to spinel-type $ZnCo_2$$O_4$with the increase of the Co/Zn sputtering ratio,$ D_{co}$ $D_{zn}$ . We noted that the above structural change accompanied by the variation of the majority electrical conduction type from n-type (electrons) to p-type (holes). For a fixed $D_{co}$ $D_{zn}$ / of 2.0 yielding homogeneous spinel-type $_2$O$ZnCo_4$films, the type of the majority carriers also varied, depending on the$ O_2$/Ar partial pressure ratio: p-type for an $O_2$-rich and n-type for an Ar-rich atmosphere. The maximum electron and hole concentrations for the Zn $Co_2$ $O_4$films were found to be 1.37${\times}$10$^{20}$ c $m^{-3}$ and 2.41${\times}$10$^{20}$ c $m^{-3}$ , respectively, with a mobility of about 0.2 $\textrm{cm}^2$/Vs and a high conductivity of about 1.8 Ω/$cm^{-1}$ /.