• 제어로봇시스템학회:학술대회논문집
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• 1999.10a
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• pp.288-291
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• 1999

The PID (Proportional-Integral-Derivative) controller is widely used in the industries for more than fifty years with the well known Ziegler-Nichols tuning method and others varieties. However, most of the PID controller being used in the real practice still require trial and error adjustment for each process after the tuning method is done, which is consuming of time and needs the operator experiences to obtain the best results for the controller parameter. In order to reduce the inconvenience in the controller tuning, this paper presents a design of an automatic PID controller parameter analyzer being used as a support instrument in the industrial process control. This analyzer is designed based on the tuning formula of Dahlin to synthesize the PID controller parameter. Using this analyzer, the time to be spent in the trial and error procedures and its complexity can be neglected. Experimental results using PID controller parameter synthesized from this analyzer to the liquid level control plant model and the fluid flow control plant model show that the responses of the controlled systems can be efficiently controlled without any difficulty in mathemathical computation.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.1
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• pp.63-70
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• 2018

Objective: The aim of the study was to isolate gossypol-degrading bacteria and to assess its potential for gossypol degradation. Methods: Rumen liquid was collected from fistulated cows grazing the experimental pasture. Approximately 1 mL of the rumen liquid was spread onto basal medium plates containing 2 g/L gossypol as the only source of carbon and was then cultured at $39^{\circ}C$ to isolate gossypol-degrading bacteria. The isolated colonies were cultured for 6 h and then their size and shape observed by microscope and scanning electron microscope. The 16S rRNA gene of isolated colonies was sequenced and aligned using National Center for Biotechnology Information-Basic Local Alignment Search Tool. The various fermentation conditions, initial pH, incubation temperature, inoculum level and fermentationperiod were analyzed in cottonseed meal (CSM). The crude protein (CP), total gossypol (TG), and free gossypol (FG) were determined in CSM after fermentation with isolated strain at $39^{\circ}C$ for 72 h. Results: Screening results showed that a single bacterial isolate, named Rumen Bacillus Subtilis (RBS), could use gossypol as a carbon source. The bacterium was identified by 16S rDNA sequencing as being 98% homologous to the sequence of Bacillus subtilis strain GH38. The optimum fermentation conditions were found to be 72 h, $39^{\circ}C$, pH 6.5, moisture 50%, inoculum level $10^7cell/g$. In the optimum fermentation conditions, the FG and TG content in fermented CSM decreased 78.86% and 49% relative to the control. The content of CP and the essential amino acids of the fermented CSM increased respectively, compared with the control. Conclusion: The isolation of a gossypol-degrading bacterium from the cow rumen is of great importance for gossypol biodegradation and may be a valuable potential source for gossypol-degradation of CSM.

• Journal of Biosystems Engineering
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• v.38 no.4
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• pp.228-239
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• 2013

Purpose: The objectives of this study were to develop an automated disinfectant dilution system, and an automated data management system for spraying amount for resolving uncertainty problem. Methods: Proper diluting rate was made by a controlled volume pump for liquid disinfectant and a screw conveyer pump for solid disinfectant. The water capacity of disinfecting system of 400 L was controlled by two water level sensors. The water quantity of water tank was controlled by the signals which were produced by the water level sensors. Signals were processed by Labview Programming, and ON/OFF of solenoid valve that was used for controlling water supplying to water tank, was controlled by SSR. The operating time of pumps for disinfectant was controlled quantitatively. A turbine flowmeter was used for development of automated measurement system for spraying amount of disinfectant. In order to save the flowmeter data and to control the spraying system, a multi-function data logger was used, and it was processed and saved in Excel file by a program developed in this study. Results: Labview 2010 was used for programming to control the automated measurement system for spraying amount of disinfectant. Results showed that the relationship between flowmeter value and time had a significant linear relationship such as 0.99 of $R^2$. Generally, 6.74 L/s of diluted disinfectant is sprayed for a vehicle passing through the disinfection system (about 15 seconds). Test results showed that average error between the measured spraying amount and the flowmeter data was 50 mL, and the range of error was 1.3%. Since the amount and time of spraying could be saved in real-time by using the spreadsheet files which could not be modified arbitrarily, it made possible to judge objectively whether the disinfection spraying was performed or not. Test results of spraying liquid and solid disinfectant showed that the errors between the measured discharge rate and the theoretical one were ranged within 3-4% for various dilution rates. Conclusions: The disinfection system developed would be working accurately. The automated spraying data base management system satisfied the purpose of this study. The automated dilution process system developed in this study could discharge liquid and solid disinfectant with accurate dilution rate, relatively.

• Journal of Powder Materials
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• v.18 no.4
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• pp.359-364
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• 2011

Zr-Ti alloy powders were successfully synthesized by magnesium thermal reduction of metal chlorides. The evaporated and mixed gasses of $ZrCl_4+TiCl_4$ were injected to liquid magnesium and the chloride components were reduced by magnesium leading to the formation of $MgCl_2$. The released Zr and Ti atoms were then condensed to particle forms inside the mixture of liquid magnesium and magnesium chloride, which could be dissolved fully in post process by 1~5% HCl solution at room temperature. By the fraction-control of individually injected $ZrCl_4$ and $TiCl_4$ gasses, the final compositions of produced alloy powders were changed in the ranges of Zr-0 wt.%~20 wt.%Ti and their purity and particle size were about 99.4% and the level of several micrometers, respectively.

• Journal of Powder Materials
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• v.11 no.4
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• pp.322-327
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• 2004

Ultrafine titanium carbide particles were synthesized by the reaction of liquid-magnesium and vaporized TiCl$_{4}$+C$_{x}$Cl$_{4}$(x = 1 and 2) solution. Fine titanium carbide particles with about 50 nm were successfully produced by combining Ti and C atoms released by chloride reduction of magnesium, and vacuum was then used to remove the residual phases of MgCl$_{2}$ and excess Mg. Small amounts of impurities such as O, Fe, Mg and Cl were detected in the product, but such problem can be solved by more precise process control. The lattice parameter of the product was 0.43267 nm, near the standard value. With respect to the reaction kinetics, the activation energy for the reactions of TiCl$_{4}$+C$_{2}$Cl$_{4}$and Mg was found to 69 kJ/mole, which was about half value against the use of TiCl$_{4}$+CCl$_{4}$, and such higher reactivity of the former contributed to increase the stoichiometry until the level of TiC$_{0.96}$ and decrease the free carbon content below 0.3 wt.%.

• Mass Spectrometry Letters
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• v.11 no.3
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• pp.59-64
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• 2020

Mertansine, a thiol-containing maytansinoid, is a tubulin inhibitor used as the cytotoxic component of antibody-drug conjugates for the treatment of cancer. Liquid chromatography-tandem mass spectrometry was described for the determination of mertansine in rat plasma. 50-μL rat plasma sample was pretreated with 25 μL of 20 mM tris-(2-carboxyethyl)-phosphine, a reducing reagent, and further vortex-mixing with 50 μL of 50 mM N-ethylmaleimide for 3 min resulted in the alkylation of thiol group in mertansine. Alkylation reaction was stopped by addition of 100 μL of sildenafil in acetonitrile (200 ng/mL), and following centrifugation, aliquot of the supernatant was analyzed by the selected reaction monitoring mode. The standard curve was linear over the range of 1-1000 ng/mL in rat plasma with the lower limit of quantification level at 1 ng/mL. The intra- and inter-day accuracies and coefficient variations for mertansine at four quality control concentrations were 96.7-113.1% and 2.6-15.0%, respectively. Using this method, the pharmacokinetics of mertansine were evaluated after intravenous administration of mertansine at doses of 0.2, 0.5, and 1 mg/kg to female Sprague Dawley rats.

• Preventive Nutrition and Food Science
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• v.15 no.3
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• pp.239-243
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• 2010

The antimicrobial effects of a commercially available, buffered sodium citrate (BSC) were evaluated for the reduction of total aerobic bacteria count, Salmonella Typhimurium, Escherichia coli O157:H7, Listeria monocytogenes and Staphylococcus aureus in a liquid medium and ground beef. BSC at 0, 1, 2 and 4.8% (wt/vol) or 0, 3, and 4.8% (wt/wt) was mixed into inoculated brain heart infusion (BHI) broth and ground beef (80% lean), respectively. BSC at concentrations of 1 and 2% did not inhibit growth of the pathogens tested in BHI broth. E. coli O157:H7 in BHI broth with 4.8% BSC was significantly reduced (p<0.05) by 3～4 log CFU/mL compared with the control for up to 4 days. At 4.8%, BSC treatment of ground beef most significantly reduced (p<0.05) total aerobic count and E. coli O157:H7 by 2.1 and 2.0 log CFU/g, respectively. This study indicates that the legally allowable level of 1.3% (wt/wt) BSC is not effective for reducing the pathogens tested in ground beef stored at $7^{\circ}C$.

• Mass Spectrometry Letters
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• v.13 no.1
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• pp.20-25
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• 2022

Fargesin, a tetrahydrofurofuranoid lignan isolated from Flos Magnoliae, shows anti-inflammatory, anti-oxidative, anti-allergic, and anti-hypertensive activities. To evaluate the pharmacokinetics of fargesin in mice, a sensitive, simple, and selective liquid chromatography-high resolution mass spectrometric method using electrospray ionization and parallel reaction monitoring mode was developed and validated for the quantification of fargesin in mouse plasma. Protein precipitation of 6 µL mouse plasma with methanol was used as sample clean-up procedure. The standard curve was linear over the range of 0.2-500 ng/mL in mouse plasma with the lower limit of quantification level at 0.2 ng/mL. The intra- and inter-day coefficient variations and accuracies for fargesin at four quality control concentrations including were 3.6-11.3% and 90.0-106.6%, respectively. Intravenously injected fargesin disappeared rapidly from the plasma with high clearance values (53.2-55.5 mL/min/kg) at 1, 2, and 4 mg/kg doses. Absolute bioavailability of fargesin was 4.1-9.6% after oral administration of fargesin at doses of 1, 2, and 4 mg/kg to mice.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.3
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• pp.225-232
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• 2015

We evaluated the effect of mixed liquid fertilizer (MLF) on growth responses of plants and soil chemical properties. A pot experiment with red pepper (Capsicum annuum L.) using loam soil was conducted for 81 days in a temperature-controlled glasshouse, and four N fertilization treatments were laid out in a completely randomized design with three replicates: control (C), chemical fertilizer treatment (CF), and two rates (MLF-0.5 and MLF-1.0) of MLF treatment. Soils were periodically sampled and analyzed for pH, EC(Electrical Conductivity), total N, inorganic N and total C, and some growth characteristics of red peppers were measured. During the experimental periods, the pH of MLF soils was higher than that of CF soils. Soil EC increased right after application of CF or MLF, and the intial increase persisted in CF and MLF soils at the end of experiment. Soil total-N increased right after application of CF or MLF, and this initial increase persisted only in MLF-1.0 soils. Soil inorganic N content initially increased in CF or MLF-1.0 soils, but the initial increase disappeared in 56 days after transplanting. Soil total-C was maintained higher in MLF-1.0 soils and lower in CF soils than in control soils, and the intial increase in MLF-1.0 soils finally disappeared to the level of control soils. Plant height, dry weight of plant organs (shoots, roots and fruit), and the number, diameter and length of red pepper fruits were greatest in CF plants. On the other hand, the effect of MLF-application was different depending on the rate of application. However, no consistent effect of N treatments on some major elements of the organs of red peppers was observed. The amounts of N taken up by plants were 1.3 g for CF, 0.8 g for MLF-1.0, 0.5 g for MLF-0.5 and 0.4 g for control treatments. The results of this study showed that mixed liquid fertilizer (MLF) could appropriately serve as an alternative to chemical N fertilizer in red pepper cultivation.

• Korean Journal of Organic Agriculture
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• v.18 no.2
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• pp.209-219
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• 2010

This study was carried out to evaluate the effects of applying levels of organic liquid fertilizer (OLF) on growth and fruit quality of hot pepper. The OLF was made with compositions of chicken dung : rice bran : soybean meal (2:1:1). Hot pepper was applied with 5 treatments; control (chemical fertilize), OLF-1.0X (standard applying levels), OLF-0.7X (70% of standard applying level), and OLF-1.3X (130% of standard applying level). The plant height was reduced at 23cm in the OLF-1.0X treatment compared to control of 293cm. The number of hot pepper fruits was significantly increased. The content of capsaicin in the ripened pepper decreased by 23.6% in the OLF-1.0X treatment with $253mg{\cdot}kg^{-1}$ compared with control of $331mg{\cdot}kg^{-1}$, but the content of free sugar increased by 19.5%. The content of capsaicin and soluble solid content in OLF-1.3X treatment were significant different with other treatments. The yield of red pepper in OLF-1.0X treatments increased by 15% with $4,190kg{\cdot}10a^{-1}$ compared to control of $3,643kg{\cdot}10a^{-1}$, and OLF-1.3X and OLF-0.7X treatments showed increase by 10% and 6%, respectively.