• The Transactions of the Korean Institute of Electrical Engineers D
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• v.50 no.3
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• pp.114-119
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• 2001

An automatic train operation(ATO) system executes the operation of constant speed travelling and fixed point parking by using microprocessors instead of driver's manual operation. This paper describes the mathematical model for the train considering unknown disturbances which consist of start resistance, travelling resistance, slope resistance, curve resistance, and so on. The speed controller of ATO system is designed by considering the disturbances. The simulation is executed to verify the speed control and fixed point parking performance and to compare its performance with that of a PID-type ATO control system under disturbances. Simulation results show that the control performance of gain scheduled control scheme for ATO system is better than that of the conventional PID controller.

• Proceedings of the KSR Conference
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• 1999.11a
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• pp.280-287
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• 1999

An automatic train operation(ATO) system executes the operation of constant speed travelling and fixed point parking by using microprocessors instead of drivers manual operation. This paper describes the mathematical model for the train considering unknown disturbances which consist of start resistance, travelling resistance, slope resistance, curve resistance, and so on. The speed controller of ATO system is designed by considering the disturbances. The simulation is executed to verify the speed control and fixed point parking performance and to compare its performance with that of a PID-type ATO control system under disturbances. Simulation results show that the control performance of gain scheduled control scheme fur ATO system is better than that of the conventional PID controller.

• Archives of Pharmacal Research
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• v.21 no.6
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• pp.671-676
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• 1998

Five hundred and seventy clinical strains of Pseudomonas aeruginosa were isolated from August 1993 to August 1994 in Korea and screened for their resistance to ciprofloxacin, norfloxacin, and ofloxacin. Among these, two P. aeruginosa strains (PA150 and PA300) were selected based on their strong resistance (MICs > 50mcg/ml) to all three quinolones. The susceptible strain as well as two resistant strains had proton gradient-dependent efflux system. Efflux system in PA300 showed different specificities to ofloxacin and ciprofloxacin while PA150 had less permeability for ofloxacin. Ofloxacin had a less inhibitory action on DNA synthesis in permeabilized cells of PA150 and PA300 than 1771M. When quinolone resistance determining region (QRDR) in gyrA was sequenced, PA300 had one missense mutation, Asn 116Tyr, which was newly reported in this work. The results showed that PA150 became ofloxacin resistant by reduced ofloxacin accumulation due to the existence of efflux system and low permeability, while resistance of PA300 was due to the efflux system and a mutation in QRDR of gyrA -the target site of quinolone.

• Journal of Acupuncture Research
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• v.17 no.4
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• pp.130-138
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• 2000

Objectives : When sweating factor is excluded, to know the influence of acupuncture stimulation on electrical resistance. Methods : Regional anaesthesia(Lidocane 2%, 1ml, Subcutaneous injection) is applied to measured regions, 4cm round area including left Neiguan P6. So we can make adiaphoresis. Before and after acupucnture stimulation to Laogong P8, we measured the electrical resistance of anesthetized left Neiguan P6, anesthetized non-acupoint, normal left Ximen P4, and normal right Neiguan P6. For measurment, we use the 1.2V, DC system that has 100$k{\Omega}$ internal resistance Results : Under the adiaphoresis, Acupuncture stimulation makes the significant decrease of electrical resistance. In normal regions, so does it. Conclusions : When the acupuncture stimulation is applied to human boby, the decrease of electrical resistance is due not only to sweat secretion but also to other internal resistance.

• Korean journal of applied entomology
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• v.32 no.4
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• pp.373-381
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• 1993

Resistance evolution to organophosphate-based pesticides in apple and pear inhabiting arthropods of western North America extends to many classes of pest and some beneficial species. Resistance management programs to minimize resistance in pests while exploiting it in natural enemies have met with mixed success. Among beneficials, resistances have been exploited mostly among predators of pest mites. Evolution of resistant mites, leafminers, leafhopper, aphids, leafrollers and some internal fruit feeders have led to development of new monitoring methods and means to delay or avoid resistance. But it is resistance to azinphosmethyl in codling moth (Cydia pomonella) that is changing the pest control system and moving it from chemical to biologically-based means. Newly merging IPM system will depend more on use of biological, cultural, behavior and genetic controls. But more selective pesticides also will be needed to augment pheromones, resistant host plants and genetically altered organisms. These more biologically-based tactics will be prone to resistance evolution in pests as well, if used too unilaterally and/or too extensively.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.6
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• pp.365-369
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• 2016

In this paper, we fabricated Cu/Mn alloy shunt resistor with low resistance and thermal stability for use of mobile electronic devices. We designed metal alloy composed of copper (Cu) and manganese (Mn) to embody in low resistance and low TCR which are conflict each other. Cu allows high electrical conductivity and Mn serves thermal stability in this Cu/Mn alloy system. We confirmed the elemental composition of the designed metal alloy system by using energy dispersive X-ray (EDX) analysis. We obtained low resistance below $10m{\Omega}$ and low temperature coefficient of resistance (TCR) below $100ppm/^{\circ}C$ from the designed Cu/Mn alloy resistor. And in order to minimize resistance change caused by alternative frequency on circuit, shape design of the metal alloy wire is performed by rolling process. Finally, we conclude that design of the metal alloy system was successfully done by alloying Cu and 3 wt% of Mn, and the Cu/Mn alloy resistor has low resistance and thermal stability.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.320-323
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• 2001

Nowadays, computer network has been rapidly developed. And we have made efforts to use it in wide field. So we can exchange data without spacial restriction using internet. If we develop monitoring system using internet, we have the effect of reducing time and space. Therefore, in this paper, we developed TCP/IP network and client/server system. And We applied them to resistance spot welding quality monitoring system.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2008.04a
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• pp.69-72
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• 2008

This study is designed to understand changes in fire resistance performance of intumescent coating system through follow-up tests on temperature of unexposed surface for the domestic intumescent coating system by environmental testing procedure.

• Journal of Power Electronics
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• v.18 no.4
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• pp.1268-1277
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• 2018

A relatively high operating frequency is required for efficient wireless power transfer (WPT). However, the alternating current (AC) resistance of coils increases sharply with operating frequency, which possibly degrades overall efficiency. Hence, the evaluation of coil AC resistance is critical in selecting operating frequency to achieve good efficiency. For a Litz wire coil, AC resistance is attributed to the magnetic field, which leads to the skin effect, the proximity effect, and the corresponding conductive resistance and inductive resistance in the coil. A numerical calculation method based on the Biot-Savart law is proposed to calculate magnetic field strength over strands in Litz wire planar spiral coils to evaluate their AC resistance. An optimized frequency can be found to achieve the maximum efficiency of a WPT system based on the predicted resistance. Sample coils are manufactured to verify the resistance analysis method. A prototype WPT system is set up to conduct the experiments. The experiments show that the proposed method can accurately predict the AC resistance of Litz wire planar spiral coils and the optimized operating frequency for maximum efficiency.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.1060-1064
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• 2010

Ground anchors are mostly used to improve the resistance capacity of retaining walls. The end of the anchor is connected to retaining wall through tendons and the forces in tendons are transferred to ground. In this study, we plan that the new anchor system increases the tension force in tendons and improves the pullout resistance characteristics of the system. In order to increase the pullout resistance capacity of existing anchor system, the new anchor system is made by attaching four steel sticks to the tip of anchor end. So the field test results showed that the pullout resistance capacity of the wedge-shaped ground anchor was acceptable to elastic displacement range.