• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.10
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• pp.739-744
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• 2018

In this paper, a double split-ring resonator(DSRR) is proposed to improve the isolation between Vivaldi antenna elements. The DSRR was designed using a unit cell simulation and applied to a $1{\times}2$ Vivaldi antenna array to confirm the improvement in the isolation. The unit cell size of the proposed DSRR is $5mm{\times}5mm{\times}1.52mm$ and six unit cells are used. To verify the performance of the proposed DSRR, $1{\times}2$ Vivaldi antenna arrays with and without the DSRR were fabricated and measured. The results show an isolation improvement of 20 dB in the Vivaldi antennas with the DSRR when compared to the Vivaldi antennas without the DSRR.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.174-176
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• 2007

Because of accident or leak of electricity, high voltage electricity can be conducted to vehicle chassis and damage human. Therefore the unit for detecting ground fault is necessary to minimize loss of life or equipment damage. Isolation resistance must be monitored for detecting ground fault. GFD(Ground Fault Detection) unit continually generate the pulse voltage between high voltage network and chassis. This will be sensing the returned current, calculate the isolation resistance and make decision the ground fault. This paper describes the method detecting ground fault.

• Proceedings of the KIEE Conference
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• 1998.07b
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• pp.410-413
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• 1998

A passive approach for enhancing fault detection and isolation performance of multiple observer based fault detection isolation schemes(FDIS) is proposed. The FDIS has a hierarchical framework to perform detection and isolation of faults of interest, and diagnosis of process faults. The decision unit comprises of a rule base and fuzzy inference engine and removes some difficulties of conventional decision unit which includes crisp logic and threshold values. Emphasis is placed on the design and evaluation methods of the diagnostic rule base. The suggested scheme is applied for the FDIS design for a DC motor driven centrifugal pump system.

• Bulletin of the Korean Chemical Society
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• v.29 no.4
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• pp.863-865
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• 2008

• Bulletin of the Korean Chemical Society
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• v.28 no.5
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• pp.877-879
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• 2007

• Smart Structures and Systems
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• v.2 no.4
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• pp.329-337
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• 2006

This paper illustrates an analytical investigation of the vibration parameters of buildings on sliding seismic isolation bearings with elastic limiters of the relative displacement. The installation scheme of sliding bearings and elastic limiters for the separate unit of a 4 storey hospital building with brick walls is designed. The analysis of the vibrations of the hospital building is conducted for harmonic base excitation.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.1
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• pp.49-55
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• 2020

In this study, the surface temperature of the roof green system using ALSRBA(Artificial Lightweight Soil Recycled with Bottom Ash) was measured in each season and the thermal property of the ALSRBA was investigated. As a result, it was certified that ALSBRA has superior thermal property than the usual artificial soil. In addition, The daily temperature range in each season was measured to investigate the thermal isolation property of EUS(Existing Unit System) and DUS(Developed Unit System). The result showed that the thermal isolation effect of EUS was lower than that of SPSS(Site-Place-Soil System), but thermal isolation effect of DUS was similar to that of SPSS because DUS has continuous ALSBRA layer by removing unit barrier.

• The Korean Journal of Mycology
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• v.22 no.2
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• pp.138-144
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• 1994

Conditions for isolation of protoplasts from spores and mycelia of Rhizopus nigricans were studied. Larger amount of protoplasts was obtained from swollen spores in liquid medium contained with 5% of 2-deoxy-D-glucose for 4 hours than from mycelia. Enzyme mixture of Novozym 234(2%) and ${\beta}-glucuronidase(5000\;unit/ml)$ was most effective for the isolation of protoplasts from swollen spores and from mycelia. The solution of 0.6 M $MgSO_4$ or mannitol and pH 6.0 showed good results as the osmotic stabilizer and the optimal condition of pH of the enzyme solution for the isolation of protoplast from the swollen spores, respectively. At this condition, $8.0{\times}10^6\;cells/ml$ of protoplasts was obtained from swollen spores by digestion with lytic enzyme mixture for 2 hours.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.465-470
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• 2002

A novel phased array antenna system for space-borne polarimetric SAR is proposed and completed in this paper.The antenna system assures polarimetric and multi-mode capability of SAR. It has broadband, high polarization isolation and high port to port isolation. The antenna system is composed of broadband polarimetric microstrip antenna, T/R modules and multifunction beam controller nit. The polarimetric microstrip antenna has more than 100MHz bandwidth at L-band with -30dB polarization isolation and high port to port isolation. The microstrip element and T/R module's structure and characteristics, the subarray's performances measuring results are presented in detail in this paper. A design scheme on beam controller of the phased array antenna is also proposed and completed, which is based on Digital Signal Processing (DSP) chip -TMS320F206. This beam controller unit has small size and high reliability compared with general beam controller. In addition, the multifunction beam controller unit can acquire and then send the T/R module's working states to detection system in real time.

• Journal of The Korea Institute of Healthcare Architecture
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• v.23 no.2
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• pp.73-82
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• 2017

Purpose: Since the facility guidelines for National Designated Isolation Unit wards(NDIUs) had been edited since 2016, all hospital who want to expand or install NDIU should adapt the new guidelines. Instead of providing area requirement, by the way, only essential or optional facility requirements are suggested except patient bedroom in the guidelines. So, as analyze area and area composition of the NDIUs, it could be expected that this study has a role as an area planing reference for not only NDIU but also another airborne infection isolation room. Methods: For the area analysis, 18 sample hospitals are selected among 2016 year applicants. All rooms in NDIUs are grouped as zones whether those are negative air pressurized or not and programed room or not. At the end, area of the zones are summarized and analysed a relationship between area increase and bed number by both correlation analysis and regression analysis. In addition, department usable and gross area per bed, N/G ratio, G/N ratio, and average area ratio of each zone is calculated. Results: First of all, rooms in none negative air pressurized zone of the NDIUs haven't shown a regular installation so that only those in negative air pressurized zone are targeted for the area analysis. Second of all, patient room unit(0.92) and support area(0.79), by correlation analysis, are correlated with total net area. Patient room unit(0.94) and total net area(0.79) are also shown a correlation with bed number. Department usable area($R^2=0.63$, y=36.278x + 102) and patient room unit area($R^2=0.89$, y= 27.993x - 0.8924) has a relationship with bed number by regression analysis. Average N/G is shown as 0.85 and G/N 1.36. Average area ratio of circulation, doffing area, patient room unit, and support area are 25.4%, 9.1%, 50.9%, and 14.6% in order. Implications: This study is a basic research for exploring the NDIUs guidelines to find resonable evidence to develop it for its practical use. Still, it is possibly expected that the guideline is to be developed by post occupancy evaluation in the area of where minimum requirement or facility grade needs to be defined, and by further studies with various perspectives.