• Journal of the Korean Ceramic Society
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• v.21 no.3
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• pp.245-252
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• 1984

Willemite phosphor is a good one having excellent luminescence efficiency that it;s emission wavelength is in the range of about 525 nm. The energy band gap of this willemite phosphor is about 4.1 eV. When the ratio of ZnO/SiO is 1.8 and Mncl in used as activator source the phosphor has the value of maximum luminescence efficiency. The characteristic of willemite phosphor is tendency of the dependence of temperature. The willemite which was fired with activator after being synthesized at initial firing without activator shows higher value of luminescence efficiency than willemite which was fired with activator in initial stage, When the concentration of activator is 1-1.5mol% it has its most favorite condition and the value of luminescence efficiency decreases according to increasement of activator concentration.

• Textile Coloration and Finishing
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• v.11 no.4
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• pp.24-30
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• 1999

Cotton fabric was dyed with indigo at different pHs, dye concentrations, and repeated dyeings. And the K/S value and dye uptake of the dyed materials at those conditions were determined. The decrease of pH during the reduction process of indigo stock solution was observed. As a result the decrease of pH of the dye stock solution depended on the dye concentration and initial pH. The highest K/S value was shown at fabric dyed at pH 11 and the relationship between K/S value and dye uptake depended on initial pH of reduction bath and the slope was lower as the pH increased to 13.

• Journal of the Korean Ceramic Society
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• v.17 no.2
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• pp.89-95
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• 1980

The effect of non-stoichimetry and sintering temperature on the magnetic properties of materials in the system $Ni_{0.39}Zn_{0.61}Fe_{2.0+x}O_4$ have been investigated. The value of x used in initial weighing of oxides were varied from -0.04 to -0.12. The value of x, however, appears to be from +0.04 to -0.04 after ferrite powder preparation due to iron pick up during ball mill mixing and grinding. The densities of specimens which were deficientinrion were higher than those with excess ion. Specimens with near stoichiometric composition showed maximum initial permeability an dminimum coercivity whereas high values of quality factor (Q) were observed in iron deficient specimens. The quality factor decreased monotonically with increasing sintering temperature, but the permeability showed maxima with increasing sintering temperature. Thus highest value of figure of merit $\mu$Q was obtained in composition $Ni_{0.39}Zn_{0.61}Fe_{1.98O4}$ sintered at 100$0^{\circ}C$ for 3 hrs. in an air atmosphere.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.29B no.3
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• pp.6-15
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• 1992

This paper proposes a method for the global optimization of redundancy over the whole task period for a kinematically redundant robot. The necessary conditions based on the calculus of variations for an integral type cost criterion result in a second-order differential equation. For a cyclic task, the periodic boundary conditions due to conservativity requirements are discussed. We refine the two-point boundary value problem to an initial value adjustment problem and suggest a numerical search method for providing the conservative global optimal solution using the gradient projection method. Since the initial joint velocity is parameterized with the number of the redundancy, we only search the parameter value in the space of as many dimensions as the number of degrees of redundancy. We show through numerical examples that multiple nonhomotopic extremal solutions and the generality of the proposed method by considering the dynamics of a robot.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.54 no.12
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• pp.629-637
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• 2005

This paper proposes a new anti-windup strategy to suppress integrator windup for PI speed controller and to be implemented on the existing system with minimal modification. When the speed control mode is changed from P controller to PI controller. an appropriate initial value for integrator is assigned. This value restricts overshoot and high settling time. Also, the proposed method guarantees the designed performance independent on operating conditions, i.e. different set-point change and load torque. Simulation and experimental results for PMSM speed controller have shown its superior performance compared with the conditional integration and tracking back calculation.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.64.5-64
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• 2001

It is a very important problem that we grasp the accurate position at car navigation system. The GPS has used for knowing position because of accumulating few errors, but it have errors that are Tropospheric error, ionospheric error and Multipath error and so on. In this paper, We estimate moving position of a vehicle by Kalman filter using initial value after deducing the line equation using initial value and target value of map data. Then, we compensate GPS errors compare estimated poing with GPS errors. The experimental results have shown that are compared position data during real travel with compensated position data which are got after applying the algorithm ...

• Journal of The Korean Society of Clinical Toxicology
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• v.2 no.2
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• pp.72-76
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• 2004

Purpose: Dealing patients with organophosphate poisoning, cholinesterase level has been used as a diagnostic and prognostic value. But there are some controversies that the cholinesterase level is significantly related to the severity or prognosis of acute organophosphate poisoning. We evaluated the correlation between initial serum level of cholinesterase and APACHE II score as an index for severity, and we assessed cholinesterase levels for predicting value of weaning from mechanical ventilation. Method: From August 1996 to March 2003, 23 patients with organophosphate poisoning who needed ventilatory care were enrolled. Retrospective review was done for the serum level of cholinesterase, APACHE II score, and the duration of ventilatory care. The percentage of measured serum cholinesterase to median normal value was used to standardize cholinesterase levels from different laboratories. Result: There were tendencies that the lower initial serum of cholinesterase, the higher the APACHE II score (r=0.297) and the longer the duration of mechanical ventilation (r=-0.204), but they were not significant (p=0.264 and p=0.351 respectively). In 9 patients whose serum cholinesterase level were checked at the time of weaning, mean of measured cholinesterase level was $10.3\pm7.60\%$ of normal value. Conclusion: There was no significant relationship between initial level of serum cholinesterase and severity or duration of mechanical ventilation. General health status of patient, amount of ingestion, toxicity of agent should be considered as important factors for severity of poisoning. And the decision of weaning should be based not solely on the cholinesterase level but on the consideration of general and respiratory state of individual patients.

• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.642-647
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• 2003

In order to investigate utilization possibility of persimmon peel as a source of vinegar, we had been examined the alcohol and acetic acid fermentations of persimmon peel. In the first stage, alcohol fermentation, alcohol content was maximum value (8.22%) in 12.43 mL/g of added water, $12.41^{\circ}Brix$ of initial sugar content and 48.05 hr of fermentation time. Acidity was minimum value (0.30%) in 12.18 mL/g of added water, $13.72^{\circ}Brix$ of initial sugar content and 46.22 hr of fermentation time. In the second stage, acetic acid fermentation, acidity was maximum value (6.40%) in 2.02% of initial acidity, 67.98 rpm of agitation rate and 6.94 day of fermentation time. Browning color was minimum value in 1.50% of initial acidity, 150.0 rpm of agitation rate and 6.0 day of fermentation time. To manufacture persimmon vinegar using persimmon peel, in the first stage, optimal alcohol fermentation conditions was 12mL/g in added water, $12^{\circ}Brix$ in initial sugar concentration and 48 hr in fermentation time. In the second stage, optimal acetic acid fermentation conditions was 1.8% in initial acidity, 70 rpm in agitation rate and 6 day in fermentation time using Acetobacter sp. PA97.

• The Korean Journal of Nuclear Medicine
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• v.6 no.1
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• pp.51-59
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• 1972

$^{86}Rb$ uptake of some organs and tissues, ego both lungs, both renal cortices. small intestine, liver and skeletal muscle were studied in the control and the rabbit subjected to pneumothorax. $^{86}Rb$ in the form of chloride mixed with physiological saline was intravenously. injected. The doses were $100{\mu}c$ for a rabbit. The rabbits were sacrificed at intervals of 10, 20, 40, and 60 seconds after the injection of $^{86}Rb$, by the injection of saturated KCI solution. After sacrification, the organ and tissue sample were quickly removed. $^{86}Rb$ uptake in gm of the organs and tissues were measured. On the basis of uptake value, administered doses and body weight, % dose/gm tissues per 200 gm body weight was calculated. Followings were the results; 1. Pneumothorax resulted in a marked elevation in $^{86}Rb$ uptake value of collapsed lung and returned to normal level lately. 2. Contralateral lung of pnemothorax also showed marked elevation in $^{86}Rb$ uptake value and recovered to normal level. 3. Initial $^{86}Rb$ uptake value of liver, small intestine of the rabbit with pneumothorax showed some elevation as compared to control, but that of late stage were similar with control. 4. Local blood flow determination by means of $^{86}Rb$ uptake were inadequate in the collapsed lung of pneumothorax. 5. It was suggested that the mechanism for the initial elevation of $^{86}Rb$ uptake value in each organs and tissue were different from each other.

• Journal of Plant Biotechnology
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• v.4 no.3
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• pp.109-115
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• 2002

Submerged cultures of Ganoderma lucidum, a valuable mushroom in traditional Chinese medicine, were used for production of bioactive Banoderic acids and Ganoderma polysaccharides. The significant effects of oxygen supply were demonstrated in both shake flasks and bioreactors. By changing the medium loading volume in a shake flask, a different value of initial volumetric oxygen transfer coefficient ($K_L$a) was obtained, and a higher $K_L$a value led to a higher biomass density and a higher productivity of both intracellular polysaccharide and ganoderic acid. In a stirred bioreactor, at an initial $K_L$a of 78.2 $h^{-1}$, a maximal cell concentration of 15.6 g/L by dry weight was obtained, as well as a maximal intracellular polysarcharide (IPS) production of 2.2 g/L and its maximal productivity of 220 mg/(L.d). An increase of initial $K_L$a led to a higher production and productivity of GA, and the GA production and productivity at an initial $K_L$a of 96.0 $h^{-1}$ was 1.8-fold those at an initial $K_L$a of 16.4 $h^{-1}$. The fundamental information obtained in this study may be useful for efficient large-scale production of these valuable bioactive products by the submerged cultures.