• Journal of Institute of Control, Robotics and Systems
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• v.5 no.6
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• pp.667-675
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• 1999

In this paper, we propose a robust controller design of RTP(Rapid Thermal Processing) system using structured uncertainty approach. Using the weighted mixed sensitivity function, we solve the robust stability problem against disturbance and temperature variation, and design a $\mu$ controller using curve fitting method against structured uncertainty. Also the reduction method should be requried because of the difficulty of implementaion with the obtained high order controller. We dal with robust stability and performance of RTP system by the design of $\mu$ controller for original model and Schur balanced reduced model. Finally the simulation results are proposed to show the validity of the proposed method.

• Journal of Power System Engineering
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• v.18 no.5
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• pp.55-59
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• 2014

This study performed experimental research to visualize the moisture content absorbed in R-22, refrigerant of refrigerator. Sulfuric acids were mixed with bromothylmol blue solution to make indicating solutions, and humidity papers were prepared by impregnation of the indicating solutions into solid supporters. Prior to the impregnation, small amount of lithium chloride was added into indicating solution. Moisture measuring cell was composed to test sensitivity of the humidity papers. Color changing characteristics of the humidity papers were also examined at various moisture contents in R-22. Color of the humidity paper varied linearly with the moisture content in R-22 in the range from 150 ppm to 300 ppm. The humidity papers showed complete color change to yellow at the moisture content of 300 ppm within 8 hours.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.458-461
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• 2003

Solid-phase microextraction (SPME) and gas chromatography/headspace techniques(HS) and flame ionization detection (GC/FID) have been combined for determination of very polar compounds in water, including the widely used gasoline oxygenates and by-products. A relatively simple extraction method using a CAR/PDMS(75${\mu}{\textrm}{m}$) SPME fiber was optimized for the routine analysis of gasoline oxygenates and by-products in groundwater and reagent water. A sodium chloride concentration of 25%(w/w) combined with an extraction time of 20 min provided the greatest sensitivity while maintaining analytical efficiency Replicate analyses in fortified reagent and groundwater spiked with microgram per liter concentrations of gasoline oxygenates and by-products indicate quantitative and reproducible recovery of these and related oxygenate compounds. Method dynamic range was 50$\mu\textrm{g}$ L-1 to 3000$\mu\textrm{g}$ L-1 for gasoline oxygenates and by-products.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1979.10a
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• pp.248.1-248
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• 1979

Sixteen temperature-sensitive mutants of Autographa californica nuclear polyhedrosis virus were isolated. Several interesting phenotypes were observed. A large proportion of the mutants were un-able to form polyhedral occlusion bodies at the nonpermissive temperature (32.5C). At 32.5C, one mutant formed plaques in which the cells lacked polyhedra. Another mutant type was defective in the production of progeny extracellular nonoccluded virus and produced a plaque consisting of only a single cell containing polyhedra at 32.5C. One mutant was defective in plaque formation, progeny nonocluded virus formation, and polyhedra formation at 32.5C. Several mutants produced nonocluded virus but failed to produce plaques or polyhedra at 32.5C. Other phenotypes were also distinguished. Complementation analyses, performed by either measuring the increase in extracellular non-ocludedvirus formation or by oberving polyhedra formation in mixed infections at 32.5C, indicated the presence of 15 complementation groups. A high frequency of recombination was observed. Four of the mutants were found to be host dependent in their temperature sensitivity for polyhedra formation.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.10
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• pp.1501-1513
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• 2001

Disturbance observer, adaptive robust control, and enhanced internal model control are model based disturbance attenuation methods famous for robust motion controller which can satisfy desired performance and robustness of high-speed/high-accuracy positioning systems. In this paper, these are shown to be the same scheme with different parameterizations. To do this, a generalized framework, called as RIC(robust internal-loop compensator) is proposed and the conventional schemes are analyzed in the RIC framework. Through this analysis, it can be shown that there are inherent similarities between the schemes and advantages of the RIC in the viewpoint of controller design. This is verified through simulations and experiments.

• Journal of Biosystems Engineering
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• v.17 no.4
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• pp.404-409
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• 1992

It is important to measure the somatic informations for stockbreeding automatization. This study was carried out for the development of wireless measurement system of sphygmus in living animals. In meauring sphygmus counting with the single-channel telemety system, a LED-photo transistor sensor showed more sensitivity to the change of blood pressure than a piezo-electric sensor based pressure sensor. The LED-photo transistor sensor resulted ${\pm}1.29%$ of measurement error of sphygmus counting. In the process of transmitting and receiving the blood pressure signal for counting sphygmus, noises were mixed with, and the noises made the counting almost impossible. Auto-correlation analysis technique was applied to the signal data to extract the sphygmus information, and the technique was proved to be very effective.

• Korean Management Science Review
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• v.18 no.2
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• pp.61-72
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• 2001

This paper presents a decision support system (DSS) for selecting the best delivery policy at an internet general shopping mall with its own distribution center and many outside enterprises linked up with the mall. The DSS provides the decision maker with the performance information of three delivery policies (individual delivery, collective delivery, mixed delivery) for the given service level, customer order pattern, direct/indirect delivery ratio, unit costs of various delivery modes, upper level of goods characteristic index for collective delivery poller, etc. Furthermore, the DSS allows the decision maker to perform the sensitivity analyses of three delivery policies for their major parameters and unit costs of delivery modes. The DSS is developed with AweSim simulation 1anguage and Visual Basic programming 1anguage.

• Korean Journal of Veterinary Research
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• v.20 no.2
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• pp.119-122
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• 1980

The udders of 28 culled dairy cows were removed at slaughter and bacteria isolated. Isolations of major known mammary pathogens comparised Staphylococcus sp. (40.7%), non-identified Gram's negative rods (33.2%) and E. coli (7.4%). In the mixed infection, Staphylococcus sp. was most frequently involved. Drug sensitivity tests were performed on several bacterial species by disc method. These tests indicated that the microorganisms isolated from clinical mastitis of dairy cows were more resistant to antimicrobial agents than the organisrms isolated from milk samples.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.55 no.12
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• pp.570-575
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• 2006

This paper develops methodology in order to consider CHP(Combined Heat and Power) capacity in the Basic Plan of Long Term Electricity Supply & Demand. We develop generating cost of CHP considering electric and heat. Also we develop mixed load duration curve which includes the electric load and heat load and then apply CHP capacity to SCM(Screening Curve Method) considering CHP feature. Accordingly, it decide the optimal CHP capacity in the Basic Plan of Long Term Electricity Supply & Demand. Also, We perform the sensitivity analysis according to cost variation.

• The Journal of the Acoustical Society of Korea
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• v.17 no.1E
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• pp.3-9
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• 1998

In this paper, a robust active noise controller is designed to reduce noise in al small cavity. Noise characteristics in the small cavity are nonlinear and we could get its model with considerable modelling errors. The objective of this paper is to minimize the effects of these modelling errors and maximize the noise reduction performance. The solution could be obtained by the H∞ robust control theory. The resulting feedback controller minimizes the H∞ norm of the mixed sensitivity function, which means the effects of uncertainties of the model are suppressed in the sense of stability and the performance is enhanced as a given specification. The designed controller is realized with analog devices such as Op. Amps and experimental results show that the controller reduces noise signal sufficiently.