• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부 B
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• pp.499-501
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• 1998

In this paper, we present a self-compensating PID controller which consists of a conventional PID controller that controls the linear components and a neural controller that controls the higher order and nonlinear components. This controller is based on the Harris's concept where he explained that the adaptive controller consists of the PID control term and the disturbance compensating term. The resulting controller's architecture is also found to be very similar to that of Wang's controller. This controller adds a self-tuning ability to the existing PID controller without replacing it by compensating the control errors through the neuro-controller. When applied to an actual magnetic levitation system which is known to be very nonlinear, it has also produced an excellent results.

• Journal of Ginseng Research
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• 제19권3호
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• pp.254-259
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• 1995

The content and composition of saponin compounds of Panax species were analyzed according to their species, region and processing type of red and white ginseng. The species employed were Korean-, Chinese-, Japanese red ginsengs, and Korean white ginseng of Panax ginseng, American- and Canadian ginsengs of Panax quinquefolium, and Panax notoinseng. Twelve main saponin components in the ginseng were identified and quantified using TLC and HPLC. All three species had remarkably different content and composition. However, within each species they were similar. Twelve major ginsenosides were determined in P. ginseng, eight in p. quinquefolium, and six in P. notoginseng. Of the components of P ginseng Rf, $Rh_1$, $Rh_2$ and Ra were not detected in P quinquefolium, and $Rb_2$, Rc, Rf, $Rh_2$, Ra and Ro not detected in P. notoinseam. Crude saponin content and protopanaxadiol/protopanaxatriol saponin ratio were compared. They were 4.81~5.24% and 1.27~ 1.45 in p. ginsengs, 7.01~7.25% and 2.12~ 2.15 in p. quinquefolium, 9.80% and 0.99 in P. notoineng. The prosapogenin and sapogenin content were different among the Panax species.

• 설비공학논문집
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• 제13권12호
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• pp.1184-1195
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• 2001

Analysis of fluid flow in rectangular ducts has been conducted since it has a wide application. The purpose is to provide experimental data for the comparison with computational results. Velocity distributions inside a rectangular duct with $90^{\circ}$ mitered elbow are measured by 5W laser doppler velocity meter for Reynolds numbers of 4,049, 8,104, and 12,186. Flow rates obtained by the integration of measured velocity profile at three cross-sections, which are inlet, middle section after the elbow, and outlet, have errors less than 0.9% among them. Turbulent fluctuation components in two directions are found to have almost similar magnitude each other at a certain location due to the isotropic characteristic of turbulence.

• 한국식품영양과학회지
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• 제19권3호
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• pp.229-233
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• 1990

The compositions of hydroperoxy fatty acid components of lipid in raw adlay powder(RAP) and processed adlay powder(PAP) stored at 35$^{\circ}C$ and PAP lipid and triglyceride(TG) autoxi야-zed 35$^{\circ}C$ were studied. During autoxidation the time taken to reach 100 of peroxide and 13-hydroperoxide isomers were the major hydroperoxy fatty acids found in oxidized adlay lipid. Lower levels of 8-. 10-, 11-, 12- and 16-hydroperoxide isomer were also observed. The composi-tions of hydroperoxy fatty acid componets obtained from sutoxidized RAP lipid and TG were similar to those of hydroperoxy fatty acid components is lipid extracted from stored RAP and PAP.

• Bulletin of the Korean Chemical Society
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• 제16권5호
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• pp.392-397
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• 1995

o-Phenylenediamine (o-PD) was electropolymerized on glassy carbon electrodes under a potential cycling condition. The resulting polymer films mediated electrons for the reduction of molecular oxygen at pH=1.0. It was found from the RDE, RRDE, and cyclic voltammetry experiments that the modified electrodes reduce oxygen to hydrogen peroxide at about 300 mV lower potential than the bare glassy carbon electrode. The polymer film consisted of more than two components. Among those, only one component was active in oxygen reduction, which was formed mainly in the earlier stage of the electropolymerization. 2,3-Diaminophenazine, a cyclic dimer of o-PD, was also active in the oxygen reduction reaction, from which it was suggested that the active polymeric component has a structural unit similar to the cyclic dimer. Finally, the electropolymerization mechanism for the formation of the active and inactive components has been proposed.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.221-222
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• 2006

This paper describes a Plasma Assisted Debinding and Sintering (PADS) equipment, which has been designed to process Metal Injection Molded (MIM) components. The use of a hybrid system combining a glow discharge with a conventional heating system makes debinding and sintering of MIM components, in the same heating cycle, a feasible industrial process. Characteristics as density, carbon content and mechanical properties are similar to traditionally processed MIM materials. The reduction of energy and gas consumption and shorter lead-times are economic advantages of PADS system. The clean environment of PADS is also an ecological advantage.

• 한국환경과학회지
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• 제32권12호
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• pp.987-990
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• 2023

This study exploded the correlation between feed and livestock manure characteristics across different livestock species. The selected farms included laying hen, fattening pig, and Hanwoo farms, with visits conducted to each farm at 1-day intervals. In the experiment, feed was provided to each livestock species every day at the same scheduled time, and samples of both feed and livestock manure were collected from each farm after 1 month. The correlation analysis revealed no significant effect on the crude protein content of the feed for each livestock species and the respective livestock manure characteristics. This could be attributed to the fact that the difference in nitrogen content of each feed did not have a substantial effect on the content of the livestock manure components or the differences in individual components were similar. Based on these results, it is crucial to conduct environmental impact assessments on farms using diverse feeding management approaches for each farm.

• Journal of Ginseng Research
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• 제4권2호
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• pp.121-132
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• 1980

In order to study the effect of Korean ginseng (Panax ginseng C. A. Meyer) components on acetic acid fermentation, ginseng extracts, sucrose, total can de saponins were added to the basal niedium respectively and surface culture was carried out at 30$^{\circ}C$. Lag ime, total acidity of the fermentation broth inhibitors and the degrees of inhibition were determined in tile course of fermentation . 1. Acetic acid fermentation was not inhibited by the addition of less than 1.93% of sucrose but the degree of inhibition was increased slightly by the addition of sucrose more than that. 2. Ginseng extract inhibited acetic acid fermentation slightly, and the degree of inhibition was similar to that of sucrose. Lag time was about 72 hours when a 20% of ginseng extract was added to the basal medium while that of the control was 22hours. 3. The free saponins inhibited acetic acid fermentation considerably, and the degree of inhibition of the saponins was about 400 folds of that of ginseng extracts. An increase of total acidity of the broth which contained 2.905% of the saponins was not observed even after one month. 4. It was presumed that some other components except saponins and sucrose in ginseng extracts counter the inbition effect of saponins on acetic acid fermentation

• 한국환경과학회지
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• 제23권9호
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• pp.1593-1600
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• 2014

Adsorption and desorption characteristics of the representative 10 kinds components consisting of gasoline vapor on activated carbon were investigated at the temperature range of $-30^{\circ}C{\sim}25^{\circ}C$. The breakthrough curves of each vapors obtained by the Thomas model were well described the breakthrough experimental results of this study. The breakthrough times of each vapors were correlated with the molecular weight, density, and vapor pressure. The breakthrough times had greater correlation with boiling point than molecular weight and density. The slope of the breakthrough curve was a proportional relationship with the rate constant (k) of Thomas model expression. The higher the slope of the breakthrough curve, the rate constant was larger. The biggest slope vapor had the smallest adsorption capacity ($q_e$). Adsorption and desorption characteristics of mixed vapor similar to the gasoline vapor were studied at room temperature ($25^{\circ}C$). The mixed vapor consisting of 9 components; group A (pentane, hexene, hexane), group B (benzene, toluene), group C (octane, ethylbenzene, xylene, nonane) was examined. Group A was not nearly adsorbed because of substitution by group C, and the desorption capacity of group A was smaller than group C. The adsorbed substances were confirmed to be Group C.

• 한국자동차공학회논문집
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• 제6권1호
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• pp.108-121
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• 1998

Using gas chromatography, the light hydrocarbon emissions were analyzed from SI engine fueled with methane and liquified petroleum gas(LPG), and the effects of fuel and engine operating condition were discussed. For this purpose, 14 species of light hydrocarbon including 1, 3-butadiene were separated, calibrated with standard gas, and measured from undiluted emissions. The brake specific hydrocarbon emission(BSHC) and ozone forming potential(BSO)3 were calculated and discussed with the changes of fuel, engine speed, load, fuel/air equivalence ratio, coolant temperature, and spark timing. As a result, exhaust emission was composed of mainly fuel composed of mainly fuel comp- onent and other olefin components of similar carbon number. The olefin components such as ethylene and propylene determine most of the ozone forming potential. The fraction of fuel component in total hydrocarbon emission was bigger with methane fuel than with LPG fuel. Also fuel fraction increased at high speed or high speed or high temperature of exhaust gas, and to lesser extent with high coolant temperature and retarded spark. However, the effect of equivalence ratio had different tendency according to fuels.