• Natural Product Sciences
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• v.12 no.1
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• pp.55-61
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• 2006

A description of simple, isocratic and precise reversed phase HPLC methods is given for simultaneous quantification of pholcodine and ephedrine hydrochloride together with either carbinoxamine maleate or terfenadine in antitussive-antihistaminic oral pharmaceutical formulations. Separations were carried out on X-Terra and symmetry shield C18 column $(250\;{\times}\;4.6\;mm,\;5\;{\mu}m)$. The used isocratic elution systems were either $0.02\;M\;KH_2PO_4-acetonitrile$ in the ratio of 75 : 25 and pH adjusted to 7.70 with orthophosphoric acid or sodium hydroxide, for syrup (method A), or 0.02 octanesulphonic acid sodium salt solution-acetonitrile-acetic acid in the ratio of 75 : 25 : 0.5 for suspension (method B). The elution of both mixtures was achieved with a flow rate of 1 ml/min. Detection was carried out by UV absorbance at wavelengths of 220 and 250 nm for syrup and suspension, respectively. The quantification of the components in synthetic mixtures and actual syrup and suspension were calculated using the internal standard technique with metoclopramide HCl and codeine phosphate as internal standards (IS), respectively. The methods, for both mixtures, were validated and met all the requirements for the quality control analysis recommended by FDA and ICH.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.1
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• pp.116-123
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• 2004

The demand for the stable and comfortable cabin of a high speed passenger ship is increasing. The study on shipboard comfort has been mainly concentrated on the motion control of a whole hull body. In this study, however, a new control system operated by two parallel robots (3RPS, 3SPR) such as the active suspension system of motor vehicle is proposed. The goal of this control is keeping zero velocity of the upper robot (cabin) although the lower robot (ship) is moving by the waves. Jacobian matrix was used to design the controller, From the simulation results, the remarkable reduction of motion of the cabin (upper platform) was observed. The 3SPR parallel robot shows better performance compared to the 3RPS robot.

• Journal of Power System Engineering
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• v.8 no.2
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• pp.53-58
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• 2004

In this paper, the semi active mount featuring Magneto rheological fluid(MR Fluid) is proposed. MR fluid is suspension of micro sized magnetizable particles in a fluid medium, and its apparent viscosity can be varied by the applied strength of magnetic field. When the controllable MR fluid is applied to mechanical devices, the devices provide simple, rapid response interfaces between electronic controls and mechanical systems. The MR fluid is applied in the conventional fluid mount for improving its performance of the mount's isolation effect. A appropriate size of the MR mount is designed and manufactured on the basis of Bingham model of MR fluid. In addition, the field dependent damping forces of MR mount are evaluated with respect to the input frequency variation.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.7
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• pp.91-98
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• 2003

In the field of precision manufacturing demanding high positioning performance, the mechanical friction in positioning device deteriorates the quality of the product and increases the cost of production for positioning devices. Therefore, we propose a contract-free linear actuator using active magnetic bearing. The structure and operating principle of the proposed system are explained, and the magnetic forces are analyzed by magnetic circuit theory to design magnetic bearings and linear actuator. With the derived equation of motion, the stability is identified. Experimental results are presented to show the feasibility.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.5
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• pp.593-600
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• 1999

This paper suggests a suboptimal control scheme of an active suspension system with an asymmetric hydraulic cylinder. In this paper a quarter car model including a nonlinear actuator dynamics is used. A feedback linearization technique is applied to obtain a linear model. An LQ regulator is designed with the linear model to keep robustness against sprung mass variation. The gain of the LQ regulator which depends on the damping coefficient of the damper is calculated by using an RBF neural network for real time application. The improvement achieved with our design is illustrated through comparative simulations.

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.2
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• pp.102-109
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• 2000

This paper deals with an observer-based preview control for semi-active suspensions. An Observer has been designed such that all the state variables and road inputs can be estimated from accelerations. Since the road input to the rear wheels is a delayed version of that to the front wheels, it can be obtained by estimating the road input to the front wheels without preview the estimated values of state and the estimated road input has been investigated. The results show that the observer-based control can provide good performance. The observer-based preview control improves the dynamic behavior of the rear axle and that of pitch motion compared to the LQ optimal control.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.268.1-268.1
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• 2013

Immobilization of conducting nanoparticles on a nanogap comprising two electrodes spaced at a distance comparable to the particle size can be used as a simple and sensitive method of detecting the particles. In this work, we have examined the performance of the nanogap devices in the measurement of metallic nanoparticles, particularly gold nanoparticles (Au NPs). Detection of pM-level Au NPs in an aqueous suspension was quite straightforward irrespective of the existence of non-conducting materials. Speed of detection or the time necessary for the completion of the measurement, however, was strongly dependent upon the immobilization process. Active trapping process was found to be much more efficient and also effective in the detection of nanoparticles than its passive counterpart.

• The Korean Journal of Rheology
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• v.11 no.2
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• pp.112-121
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• 1999

An MR(Magneto-Rheological) fluids damper is designed and applied to vibration suppression of a 1/4 car model. The damping constant of MR damper changes according to input current which is controlled in a semi-active way. Several control algorithms are compared in simulations and experiments. The advantage of the proposed Frequency shaped LQ control is that passenger comfort is emphasized in the range of 4~8Hz and driving safety is emphasized around the resonance frequency of unsprung mass.

• Korean Journal of Pharmacognosy
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• v.46 no.3
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• pp.203-207
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• 2015

This study was performed to examine the antigenic potential of purified bee venom (Apis mellifera L., PBV) collected using bee venom collector. Antigenic potential of PBV was examined by active systemic anaphylaxis (ASA) in guinea pigs. PBV was subcutaneously administered at 0.025 and 0.05 mg/kg and also as a suspension with adjuvant (Freund's complete adjuvant, FCA). Ovalbumin (OVA) as a suspension with adjuvant was used to introduce positive control response. In the weight measurement and clinical observation, experimental groups didn't show any significant changes compared with control group. In the autopsy of body, the abnormalities of lung were detected only in the positive control. In the ASA test, experimental groups didn't show any symptoms of anaphylaxis like piloerection, hyperpnea and staggering gait. These results suggested that PBV didn't have antigenic potential in guinea pig.

• Toxicological Research
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• v.21 no.3
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• pp.241-247
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• 2005

HM10760 is a recombinant human erythropoietin that has beer developed as a drug for anemia. In this study, antigenic potential of HM10760 was examined by active systemic anaphylaxis in guinea pigs and passive cutaneous anaphylaxis in a guinea pig-guinea pig system. HM10760 was subcutaneously administered at 0, 2, and $20{\mu}g/kg$ and also as a suspension with adjuvant ($20{\mu}g/kg$ + FCA). Ovalbumin as a suspension with adjuvant was administered to induce positive control responses. In the active systemic anaphylaxis test, no symptoms except rubbing or licking nose and urination that were considered as physiological phenomena were observed at $0{\mu}g/kg$. Four of 5 animals at $2{\mu}g/kg$ and all the 5 animals at $20{\mu}g/kg$ showed cyanosis and lying on side. All animals in the adjuvant mixture group showed relatively mild symptoms such as rubbing or licking nose, urination, and evacuation. In the passive cutaneous anaphylaxis test, 0/5, 3/5, and 5/5 serum samples from the animals immunized with 0, 2, and $20{\mu}g/kg$, respectively, showed positive reactions against HM10760. All 5 sera collected from the animals immunized with an adjuvant mixture contained HM10760-specific antibodies. These results suggest HM10760 have antigenicity in guinea pigs.