• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.331-335
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• 2001

This paper presents the self-commissioning for surface-mounted permanent magnet synchronous motor. The proposed strategy executes three tests with a standard inverter drive system. To do this, synchronous d-q axes currents are appropriately controlled for each test. From the three tests, armature resistance, armature inductance, equivalent iron loss resistance, and emf coefficient are identified automatically. The validity of the proposed strategy is confirmed by experimental results.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05a
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• pp.358-361
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• 2006

For giving self-diagnosing capability, a method based on monitoring the changes in the electrical resistance of carbon materials in strengthened concrete has been tested. Then after examining change in the value of electrical resistance of carbon materials used as a rib of CFGFRP or a sheet of carbon fiber before and after the occurrence of cracks and fracture in hybrid FRP or carbon fiber sheet strengthened concrete at each flexural weight-stage, the correlations of each factors were analyzed.

• 전기의세계
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• v.22 no.4
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• pp.11-16
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• 1973

This paper presents an optimum control of the field resistance for the self-excited DC shunt generator to keep a constant terminal voltage in case of the load change or the torque variation in the system. The non-linearity of the system is linearized by applying the small signal technique and the linearized equation is solved by the maximum principle with the digital computer. The optimal control value of the field resistance for the step error of the generator output voltage is obtained and the transient voltage characteristics in the system are investigated.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1197-1199
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• 2009

Self-alignment for the fabrication of printed thin film transistors has become of great interest because of the resolution and registration limits of printing technologies. In this work, self-patterning and selfregistration processes are introduced, which do not need surface energy patterning and the resulting minimum gate channel length could be down to $11.2{\mu}m$ with the sheet resistance of 2.6 ${\Omega}/{\square]$ for the source and drain electrodes.

• Journal of Advanced Marine Engineering and Technology
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• v.36 no.2
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• pp.276-285
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• 2012

The objective of this research is to develop the coating technique by a porous self-fluxing alloy for improving the mechanical properties of run-out table roller surface with the hot rolling. To enhance the durability of run-out table roller with the hot rolling, the high hardness of roller surface should be maintained at high temperatures, and the improvement of wear resistance, corrosion resistance, heat resistance, burn resistance and adhesion resistance should be maintained. In order to be able to transport reliably a hot rolled steel sheet, also, the appropriate friction coefficient on the roller surface should be maintained and the slip between roller and steel should not occur. In this study, the wear resistance of roller increases after the self-fluxing alloy is changed to a cermet by adding the tungsten carbide(WC), and the coefficient of friction increases and the ability of grip is improved because the porosities are made by coating with fine iron powder on the roller surface. As a result, it is found that the ability of grip between the steel and the roller coated by a porous self-fluxing alloy contained to 5 ~ 10 wt% of Fe in the coating layer is improved compared to the roller coated by Ni-Cr. This is because the porosities are made after Fe contained in the roller is partially alloyed by heating with a furnace in the fusing process and the rest is eliminated by oxidation and dissolution.

• Journal of the Korean Society for Nondestructive Testing
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• v.27 no.2
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• pp.115-123
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• 2007

For investigating self-diagnosis applicability, a method based on monitoring the changes in the electrical resistance of carbon fiber reinforced concrete has been tested. Then after examining change in the value of electrical resistance at each flexural weight-stage of carbon fiber in CFGFRP (carbon fiber and glass fiber reinforcing plastic) with new type rib and carbon sheet for concrete reinforcing, the correlations of electrical resistance and load as a function of strain, deflection were analyzed. As the results, it is clarified that when carbon fiber rod, rib and sheet fracture, the electrical resistance of it increase largely, and specially in case of CFGFRP, afterwards glass fiber tows can be resist the load due to the presence of the hybrid (carbon and glass) reinforced fiber. Therefore, it can be recognized that reinforcing bar and new type rib of CFGFRP and sheet of CF could be applied for self-diagnosis of fracture in reinforced FRP concrete.

• Journal of the Korea Concrete Institute
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• v.18 no.3 s.93
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• pp.439-445
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• 2006

For investigating self-diagnosis applicability, a method based on monitoring the changes in the electrical resistance of hybrid FRP(having electrical property) reinforced concrete has been tested. Then after examining change in the value of electrical resistance of carbon fiber in CFRP(non-hybrid type), CFGFRP and CFAFRP(hybrid type) before and after the occurrence of cracks and fracture in non-hybrid and hybrid FRP reinforced concrete at each flexural weight-stage, the correlations of each factors(the changes in electrical resistance and load as a function of strain, deflection) were analyzed. As the results, it is clarified that when the carbon fiber tows fracture, the electrical resistance of it increase largely, and afterwards hybrid FRP composites can be resist the load due to the presence of the reinforced fiber, for example, glass fiber or aramid fiber tows. Therefore, it can be recognized that hybrid FRP(including carbon fiber) reinforcing bar could be applied for self-diagnosis of fracture in reinforced FRP concrete fracture.

• Journal of the Society of Naval Architects of Korea
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• v.48 no.2
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• pp.147-157
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• 2011

A RANS(Reynolds averaged Navier-Stokes) based numerical method is developed for the evaluation of ship resistance and self-propulsion performances. In the usability aspect of CFD for the hull form design, the field grid around practical hull forms is generated by solving a grid Poisson equation based on the hull surface grid generated from station offsets and centerline profile. A body force technique is introduced to model the effects of the propeller in which the propeller loads are obtained from potential flow analysis using an unsteady lifting surface method. The free surface is captured by using a two-phase level-set method and the realizable $k-{\varepsilon}$ model is used for turbulence closure. The hull attitude in vertical plane, i.e., trim and sinkage, is calculated by using a quasi-steady method and then considered in the computation by translating and rotating the grid system according to the values. For the validation of the proposed method, the numerical results of resistance tests for KCS, KLNG, and KVLCC1 and of self-propulsion test for KCS are compared with experimental data.

• Journal of Korean Medicine Rehabilitation
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• v.21 no.1
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• pp.137-148
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• 2011

Objectives : This study was to investigate the visual bio-feedback training for 5 weeks on balance and postural control for patients with stroke. Methods : The 26 subjects were randomly selected from the patients of the E hospital in the S city who met the study conditions. They were divided into a visual bio-feedback training group of 13 patients and a self-resistance exercise group of 13 patients. The visual bio-feedback training group received visual bio-feedback and general physiotherapy for five weeks and the self-resistance exercise group received cycling and general physiotherapy for the same period. The subjects were measured and compared for stability index, weight distribution index, fall down index, functional reach test and timed up and go test before and after the program. Results : The visual bio-feedback training group showed significant changes after the experiment in stability index, weight distribution index, functional reach test and timed up and go test(p<0.05), and the self-resistance exercise group also showed significant differences(p<0.05). The changes between prior to and after the experiment show that the visual bio-feedback training group had more significant effects than the self-resistance exercise group(p<0.05). Conclusions : The visual bio-feedback training for five weeks had effects in the improvement of the balance and posture control of stroke patients. Based on these results, more effective training programs should be developed and propagated.

• Journal of the Society of Naval Architects of Korea
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• v.60 no.5
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• pp.320-331
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• 2023

In this study, a model test was conducted using the soft-mooring technique to evaluate the added resistance of the ship in waves. The study also examined the specific factors that should be considered during the soft-mooring test. The main purpose of soft-mooring is to prevent drifting caused by waves by providing horizontal restoring forces. However, it can also create undesired restoring forces in the vertical direction. Therefore, we examined the restoring force of the ship's 6-DOF motion based on the arrangement of the soft-mooring and the height of the mooring connection point. We also checked the corresponding resonance period and drift distance. The soft-mooring test was conducted twice, once with self-propulsion and once without self-propulsion, allowing us to review the advantages and disadvantages of each test technique. The main parameters measured in these model tests were 6DOF motion and added resistance on the ship. We compared these measurements obtained from two different techniques (with and without self-propulsion). Additionally, we also compared the measurements based on the types of measuring sensors used (2D load cells on FP, AP, and 1D load cells on each mooring line) as well as the height of the mooring connection point.