• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.5
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• pp.681-691
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• 2008

Taking into consideration both the inconveniences reported with current working uniform for the aircraft mechanics and the subjects' requirements mentioned in preceded survey, the researchers designed an ergonomic sample garments with improved motional flexibility and comfort. To improve motional flexibility, extra folds were added to the back of the garments to allow for ease of motion of limbs, so that the material would not be drawn up by the motion of the arms. Darts were added to the elbow, hip, the knee. Furthermore, by increasing the length of the waist centerline, the hip region would not be drawn up. For improved comfort, $CoolMax^{(R)}$ was used as lining material for the armpit and back region to discharge swear promptly. Subjects and panels were asked to evaluate the sample garment that followed an ergonomic design and pattern. According to the results, the sample garment was evaluated more highly than the existing working uniform in appearance and motional flexibility. The field tests by three aircraft mechanics working in the Office of Forestry were also demonstrated that the sample garment was advanced in terms of motional flexibility and comfort.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.32 no.5
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• pp.307-321
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• 2020

The design and the construction are carried out by installation of new caissons on the back or the front of old caissons to increase the stability of old caisson breakwater. In this study, we use the eigenfunction expansion method to analyze the effects of wave structure interaction when new circular caissons are installed on the back or the front of old caissons. The comparison of numerical results between present method and Williams and Li is made, and the wave force and the wave run-up acting on each circular caisson are calculated for various parameters by considering the wave structure interaction.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.53 no.4
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• pp.221-226
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• 2004

Power system has recently used Double-circuit Line and Multi-circuit Line in the industrial development. This has an advantage of system stability and reliability, but the complexity of the system has a disadvantage that makes it difficult to protect the power line. Double-circuit Line has two operation conditions in the Single-circuit operation and Double-circuit operation, so it has mutual impedance. To make it possible for the remaining single-line to operate independently while there is a fault with first line or when maintenance is needed, a trip region for the single-circuit operation should be set in order to set the relay trip region. An optimal trip region for each operation, a different operational conditions for the relay setting should be calculated. In this paper, trip regions of each operation condition have been compared by considering mutual impedance and fault resistance that led to the calculation of fault impedance. Also, as we know that one of the advantages in the distance relay is the back-up protection, we calculated the trip region(Zone-2) in consideration of the mutual impedance.

• Nuclear Engineering and Technology
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• v.38 no.4
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• pp.383-390
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• 2006

Having its roots in medical applications, industrial gamma ray CT has opened up new roads far investigating and modeling industrial processes. Using a line of research related to industrial gamma ray CT, the authors set up a system of single source and detector gamma transmission tomography for wood timber and a packed bed phantom. The hardware of the CT system consists of two servo motors, a data logger, a computer, a radiation source and a radiation detector. One motor simultaneously moves the source and the detector for a parallel beam scanning, whereas the other motor rotates the scan table at a preset projection angle. The image is reconstructed from the measured projections by the filtered back projection method. The phantom was designed to simulate a cross section of a packed bed with a void. The radiation source was 20mCi of Cs-137 and the detector was a 1 inch $\times$ 1 inch NaI (TI) scintillator shielded by a lead collimator. The experimental gamma ray CT image has sufficient resolution to reveal air holes and the density distribution inside the phantom. The system could possibly be applied to a packed bed column or a pipe flow in a petrochemical plant.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.53 no.4
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• pp.221-221
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• 2004

Power system has recently used Double-circuit Line and Multi-circuit Line in the industrial development. This has an advantage of system stability and reliability, but the complexity of the system has a disadvantage that makes it difficult to protect the power line. Double-circuit Line has two operation conditions in the Single-circuit operation and Double-circuit operation, so it has mutual impedance. To make it possible for the remaining single-line to operate independently while there is a fault with first line or when maintenance is needed, a trip region for the single-circuit operation should be set in order to set the relay trip region. An optimal trip region for each operation, a different operational conditions for the relay setting should be calculated. In this paper, trip regions of each operation condition have been compared by considering mutual impedance and fault resistance that led to the calculation of fault impedance. Also, as we know that one of the advantages in the distance relay is the back-up protection, we calculated the trip region(Zone-2) in consideration of the mutual impedance.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.12 no.4
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• pp.100-105
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• 1998

This paper proposes a new control strategy of bidirectional uninterruptible power supply (UPS) with the performance of active power filter which compensates the harmonics and reactive power. With only one power stage, it is working simultaneously as the AC/DC rectifier/battery charger and DC/AC inverter to the operation of battery charging or back-up power supplying. Therefore the operation of the proposed system can be divided into the modes, such as the active power filter mode and the battery back-up power mode. And a novel closed-loop control strategy is used to calculate the reference current. The performance of the proposed 5[kVA] system is verified by the simulation and experimental results.

• The Transactions of the Korean Institute of Power Electronics
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• v.16 no.1
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• pp.20-29
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• 2011

This paper proposes critical load following back-up system using MCFC stack. This system enables MCFC generation system to supply power to critical load without UPS and to generate rated power under grid fault state. This back-up system includes 'Load Leveler' that is connected with 3-phase inverter and is controlled by additional algorithm that includes critical load following. The proposed system and algorithm are verified by computer simulation based on 5kW system.

• Journal of the Korean Institute of Intelligent Systems
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• v.6 no.3
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• pp.51-62
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• 1996

Electro sensitive traffic system can not consider passenger car unit, so it causes start up delay time and passenger waiting time. In this paper, it antecedently creates passenger car unit at the bottom intersection using neural network. But, sometimes it can make mistakes due to changes in car weight, car speed, and passing area. Therefore, it consequently reduces the car waiting time and start-up delay time using fuzzy control of feed-back data. Moreover, to prevent spillback, it can adapt control even though upper traffic intersection has a different saturation rate, road length, road slope and road width.

• Bulletin of the Korean Chemical Society
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• v.19 no.4
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• pp.422-428
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• 1998

In the present paper, we report a molecular dynamics (MD) simulation of non-rigid zeolite-A framework only as the base case for a consistent study of the role of intraframework interaction on several zeolite-A systems using the same technique in our previous studies of rigid zeolite-A frameworks. Usual bond stretching, bond angle bending, torsional rotational, and non-bonded Lennard-Jones and electrostatic interactions are considered as intraframework interaction potentials. The comparison of experimental and calculated structural parameters confirms the validity of our MD simulation for zeolite-A framework. The radial distribution functions of non-rigid zeolite-A framework atoms characterize the vibrational motion of the framework atoms. Mean square displacements are all periodic with a short period of 0.08 ps and a slow change in the amplitude of the vibration with a long period of 0.53 ps. The displacement auto-correlation (DAC) and neighbor-correlation (DNC) functions describe the up-and-down motion of the framework atoms from the center of α-cage and the back-and-forth motion on each ring window from the center of each window. The DAC and DNC functions of the framework atoms from the center of α-cage at the 8-ring windows have the same period of the up-and-down motion, but those functions from the center of 8-ring window at the 8-ring windows are of different periods of the back-and-forth motion.

• Mycobiology
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• v.50 no.6
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• pp.429-438
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• 2022

Two fungal strains belonging to Ascomycota were discovered in Gyeonggi-do, Korea, during this investigation of soil microfungi and microbiota of insects. The strain KNUF-20-047 produced milky white on the back and a milky creamy center to white toward the margin on the front side of colonies. Conversely, the closest Xenoacremonium falcatus displayed a pale luteous to luteous center, white toward margins on the front side, and pale luteous or luteous pigment on the back side, whereas X. recifei produced white colonies. The conidiophores of KNUF-20-047 were slightly larger than those of X. falcatus, and the conidia were distinct from X. recifei. Strain KNUF-20-NI-005 produced light brown to subhyaline conidiophores up to 56.0 lm tall, whereas Rhinocladiella anceps displayed golden to dark brown conidiophores up to 350 lm. Strain KNUF-20-NI-005 also produced larger conidia than R. anceps but smaller than R. coryli and R. fasciculata. Moreover, the molecular phylogeny strongly supports the detailed description and illustration of each proposed species to be designated as Xenoacremonium minutisporum sp. nov. and Rhinocladiella terrigenum sp. nov. in Korea.