• Proceedings of the KIEE Conference
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• 1998.11b
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• pp.445-447
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• 1998

This paper shows simulation results for stability and performance of two INS/GPS integration systems. First, the code tracking error of GPS receiver is analyzed by spectrum analysis and simulated for the tight and loose INS/GPS integrations. Next, stability of the integrated systems are simulated using root locus method. As loop filter in the GPS receiver, passive filter and active filter are used and compared.

• Proceedings of the KIPE Conference
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• 2017.07a
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• pp.98-99
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• 2017

A discrete time domain modeling for the current-mode-controlled buck LED driver is presented in this paper. Based on the modeling result, a root locus analysis for the buck LED driver with slope compensation is done to derive the stability boundaries of feedback gains.

• Journal of Drive and Control
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• v.16 no.4
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• pp.16-22
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• 2019

The electro-hydraulic training device (TP511) provided by Festo Didactic are widely used, but teaching materials do not include mathematical modeling. Thus, there is a limit for full-scale learning about the electro-hydraulic servo system by using this equipment. In this study, for the purpose of improving students' understanding of the classical control and modern control Festo's electro-hydraulic servo training device (TP511) was mathematically modeled and parameter values were calculated by examining the characteristics of each component. And P, PI, PD, and PID controllers highly used in the industrial field, were designed by using the root locus method to achieve the optimal gains and used for simulation and experiments using the Festo's electro-hydraulic servo training apparatus. The validity of the derived mathematical model and the calculated parameter values were verified through simulation and experiment. It was found that the p control can achieve the control target more effectively than the pid control for Festo's electro-hydraulic servo training system by using the root locus method.

• The Journal of the Korea institute of electronic communication sciences
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• v.12 no.1
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• pp.85-92
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• 2017

Recently, electric propulsion systems are used for unmanned surface vehicle, fish finder boat, etc. Some of these propulsion systems can be constructed of two electric motors and propellers for advanced impellent force. In this case, the speed difference generated between two propellers, namely, the synchronous error has a bad influence on the energy efficiency and course error. In this study, a synchronous control system is designed to restrain synchronous error caused by disturbance and mismatched dynamic characteristics. The control system is composed of the reference model, pre-filters, speed controllers, and synchronous controllers. The reference model is used for calculating the decoupled synchronous error and control input for each propulsion system. The pre-filters and speed controllers are designed in order that the propulsion system may follow the reference signal without overshoot and input saturation. And the synchronous controllers are designed from the viewpoint of stable and quick synchronization through root locus mothed approach. Finally, the simulation results show that the designed control system is effective for the disturbance.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.16 no.2
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• pp.45-53
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• 2002

This paper presents an algorithm for the appropriate parameter selection of a power system stabilizer and power converters in two-area power systems with a series HVDC links. The method for PSS is one of the classical techniques by allocating properly poly-zero positions to fit as closely as desired the ideal phase lead and by changing the gain to produce a necessary damping torque. Proper parameter of power converters are obtained in order to have sufficient speed and stability margin to cope with changing reference values and disturbances based on the Root-locus technique. The small signal and transient stability studies using the PSS and power converters parameters obtained from these methods show that a natural oscillation frequency of the study case system is adequately damped. The simulation used in the paper was performed by the Power System Toolbox software program based on MATLAB.

• The Transactions of the Korea Information Processing Society
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• v.6 no.4
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• pp.952-958
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• 1999

This paper presented the application of GAs as a means of finding optimal solutions over a parameter space in the controller design for a fuzzy control system. The performance can involve a weighted combination of various performance characteristics such as rise-time, settling-time, settling-time, overshoot. The results obtained here are compared with those for a traditional design obtained using the root-locus method. In contrast to traditional methods, the GA-based method does not require the usual mathematical processess or mathematical model of the system. In this paper, the Ga-based Fuzzy control system combining Fuzzy control theory with the GA, that is known to be very effective in the optimization problem, will be proposed The effectiveness of the proposed control system will be demonstrated by computer simulations using task tracking position system in stable and unstable linear systems. It is shown that the GA-based controller is better than the traditional controller used It stable and unstable linear systems.

• Journal of Acupuncture Research
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• v.18 no.2
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• pp.200-213
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• 2001

Objectives : This study was purposed to investigate the Anti-inflammatory and Analgesic Effects of Gold injection Aqua-acupuncture on the experimental model of rheumatoid arthritis. Methods : The experimental groups were divided into 4 groups : Control group (group injected with normal saline), J-NS (group injected with normal saline into bilateral Choksamni(ST36)), J-GS (group injected with Gold Injection into bilateral Choksamni(ST36)), and N-GS (injected with Gold Injection into the blank locus of the root of mouse tail). In addition, Diclofenac-Na as a comparative medicine is injected into bilateral Choksamni(ST36) and the blank locus of the root of mouse tail. So we measured the mice paw edema induced by Carrageenin and Dextran, the chronic rat paw edema induced by adjuvant, vascular permeability induced by Acetic acid in mice, the writhing syndrome induced by Acetic acid in mice, the heat-induced pain threshold in mice. Results : The following result have been obtained. 1. The mice paw edema induced by Carrageenin was significantly decreased in J-GS as compared with the control group. 2. The mice paw edema induced by Dextran was significantly decreased in J-GS and N-GS as compared with the control group. 3. The chronic rat paw edema induced by Adjuvant was significantly decreased in J-GS and N-GS as compared with the control group. Serum Iron content was significantly decreased in J-GS and N-GS as compared with the control group. But the effect on the Serum Copper contents has no significance statistically. 4. Vascular permeability induced by Acetic acid in mice was significantly decreased in J-GS and N-GS as compared with the control group. 5. The level of Acetic acid-induced Writhing syndrome and Heat-induced Pain Threshold in mice were all significantly decreased in J-GS and N-GS as compared with the control group. Conclusion : According to the result, gold injection aqua-acupuncture has significant anti-inflammatory and analgesic effects on the experimental model of rheumatiod arthiritis.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.5
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• pp.843-850
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• 2016

In this paper, we propose a digital controller design process for the interleaved type of a boost PFC (Power Factor Correction) converter which can disperse the heat of the switching devices due to the interleaved topology. We establish a mathematical model of a boost PFC converter and propose a controller design method based on the root locus. The performance of the designed controller is verified by simulations. The measurement of the input voltage, inductor currents, and the converter output link voltage are needed for the control of the converter system which consists of a power unit and a control unit where a high-performance 32-bit microcontroller is used. The adjustment of A/D conversion timing is also needed to avoid high frequency noise generated when the switches on/off. It is illustrated by the real experiments that the designed control system with the properly adjusted ADC timing satisfies the given performance specifications of the interleaved boost PFC converter in the on-board slow battery charger.

• Molecules and Cells
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• v.41 no.12
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• pp.1033-1044
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• 2018

As sessile organisms, plants have evolved to adjust their growth and development to environmental changes. It has been well documented that the crosstalk between different plant hormones plays important roles in the coordination of growth and development of the plant. Here, we describe a novel recessive mutant, mildly insensitive to ethylene (mine), which displayed insensitivity to the ethylene precursor, ACC (1-aminocyclopropane-1-carboxylic acid), in the root under the dark-grown conditions. By contrast, mine roots exhibited a normal growth response to exogenous IAA (indole-3-acetic acid). Thus, it appears that the growth responses of mine to ACC and IAA resemble those of weak ethylene insensitive (wei) mutants. To understand the molecular events underlying the crosstalk between ethylene and auxin in the root, we identified the MINE locus and found that the MINE gene encodes the pyridoxine 5′-phosphate (PNP)/pyridoxamine 5′-phosphate (PMP) oxidase, PDX3. Our results revealed that MINE/PDX3 likely plays a role in the conversion of the auxin precursor tryptophan to indole-3-pyruvic acid in the auxin biosynthesis pathway, in which TAA1 (TRYPTOPHAN AMINOTRANSFERASE OF ARABIDOPSIS 1) and its related genes (TRYPTOPHAN AMINOTRANSFERASE RELATED 1 and 2; TAR1 and TAR2) are involved. Considering that TAA1 and TARs belong to a subgroup of PLP (pyridoxal-5′-phosphate)-dependent enzymes, we propose that PLP produced by MINE/PDX3 acts as a cofactor in TAA1/TAR-dependent auxin biosynthesis induced by ethylene, which in turn influences the crosstalk between ethylene and auxin in the Arabidopsis root.

• Communications for Statistical Applications and Methods
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• v.16 no.6
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• pp.1037-1046
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• 2009

Copy number variations(CNVs) are known as one of the most important factors in susceptibility to genetic disorders because they affect expression levels of genes. In previous studies, pyrosequencing, mini-sequencing real-time polymerase chain reaction(PCR), invader assays and other techniques have been used to detect CNVs. However, the higher the copy number in a genome, the more difficult it is to resolve the copies, so a more accurate method for measuring CNVs and assigning genotype is needed. PCR followed by a quantitative oligonucleotide ligation assay(qOLA) was developed for quantifying CNVs. The aim of this study was to compare the two methods for detecting and quantifying the CNVs of duplicated gene: the published pyrosequencing assay(pyro_CNV) and the newly developed qOLA_CNV. The accuracy and precision of the assay were evaluated for porcine KIT, which was selected as a model locus. Overall, the root mean squares(RMSs) of bias and standard deviation of qOLA_CNV were 2.09 and 0.45, respectively. These values are less than half of those of pyro CNV.