• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.5
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• pp.42-48
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• 2017

When concrete structures expose to fire, the structures were damaged accompanied with degradation of material properties of concrete. In order to determine the reuse of fire-damaged concrete structures, it is needed a careful determination considering conditions of fire damage, such as exposure temperature and exposure time, and also potential to restore fire damage. This study investigates on the evaluation of residual material properties of fire-damaged concrete under different post-fire curing regimes. An experimental study was performed on concrete samples to measure the dynamic elastic modulus by the impact resonance vibration method. Upon the experimental results, the evidence of restoration of material properties was confirmed on specific post-fire curing regimes, higher humidity conditions. Additionally, a correlation analysis was performed on the dynamic elastic modulus with the tensile strength for identifying the effects of post-fire curing regimes on both material properties of fire-damaged concrete.

• Journal of Digital Convergence
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• v.22 no.1
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• pp.23-32
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• 2024

This study selected in-depth discharge damage survey data and analyzed 92,364 patients whose main diagnosis was S00-T98 (damage, addiction, and specific other results due to external factors) based on the Korean Standard Classification of Diseases and Deaths (KCD-7th) among patients discharged from the hospital after inpatient treatment from January 2016 to December 2018. As a result of analyzing the general characteristics of injured and traumatic patients, the incidence rate of men was higher in gender, and the incidence rate of women increased as the year increased. As a result of analyzing the characteristics of injury and trauma patients other than injury, the injury intention had a high rate of unintentional damage, the damage place was the highest on the road/road, and it showed a decreasing trend as the year increased, and it showed an increasing trend in the residential area. It can be used as basic data for the establishment of a related system to prevent damage as a result of subsang.

• KEPCO Journal on Electric Power and Energy
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• v.2 no.4
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• pp.619-625
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• 2016

In this paper, we propose a new fault diagnosis monitoring system using gyro sensor-based angular velocity calculation for blades of the wind turbine system. First, the proposed system generates the angular velocity dataset for the rotation speed of the normal blade. Using the dataset, we estimate and evaluate the state of blades for the wind turbine by comparing the current state with the pre-calculated normal state. In the experimental results, the angular velocity of the normal state was higher than $360^{\circ}/s$ while that of the damaged blades was lower than $360^{\circ}/s$ and the standard deviation of the angular velocity was significantly increased.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2003.10a
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• pp.267-270
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• 2003

An intelligent performance diagnostic computer program of a gas turbine using the NN(Neural Network) was developed. Recently on-condition performance monitoring of major gas path components using the GPA(Gas Path Analysis) method has been performed in analyzing of engine faults. However because the types and severities of engine faults are various and complex, it is not easy that all fault conditions of the engine would be monitored only by the GPA approach. Therefore in order to solve this problem, application of using the NNs for learning and diagnosis would be required. Among then, a BPN (Back Propagation Neural Network) with one hidden layer, which can use an updating learning rate, was proposed for diagnostics of PT6A-62 turboprop engine in this work.

• Journal of Conservation Science
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• v.32 no.2
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• pp.235-247
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• 2016

Conventional imaging techniques such as ultraviolet, infrared, and X-ray are used mainly to diagnose the damaged parts of the painted cultural assets in Korea. These techniques, however, have limits in diagnosing damages of interlayer parts. We have performed and extensive study on the applicability of Terahertz(THz) analysis technique, introduced recently to this field of study on cultural properties in Korea, to diagnose painted cultural assets. The specimens, produced to imitate the damage types of Korean painted properties, were analyzed over their painting, supporting, and backing layers by terahertz pulse imaging technique. The analyzed results provided information about the cracks, the separated areas, and the separated distances between layers on the specimens. Our research, then, was extended to real painted cultural remains, Birojana Sam-shin Gwebul-do at Bongseon Temple in Namyang-ju, Korea National Treasure Number 1792, through which we have obtained 3D information about the extent and pattern of damages to the asset. These results demonstrate that terahertz 3D imaging technique has the capability of noncontact 3D diagnosis on painted cultural properties.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.5 no.1
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• pp.54-69
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• 1994

The purpose of present study was to develop the Korean Version of Luria-Nebraska Neuropsychological Battery for Children(LNNB-C), to examine the reliability of it, and to establish the norms for determining the probability of brain damage. The normative group used to standardize the Korean version of LNNB-C was composed of 147 children between the age of 8 and 12(body 74, girl 73). The clinical group consisted of 19 brain damaged, 16 ADHD, and 16 psychiatric controls. The inter-scorer reliability was 96.3%, indicating that the stability of the scoring system for the Korean version of LNNB-C is good. The reliability coefficients(Cronbach's ${\alpha}$) of LNNB-C scales were ranged .51 to .91, which are similar to those of original LNNB-C. To establish the norms for detecting brain damage, the means and standard deviations for normative group were used to calculate T-scores for each scale. To determine a critical level that could successfully predict a normal child's average score at a given age, first the average score of normative group was calculated, and this score was then entered a regression equation with age to predict the average(baseline) acore. Finally, some issues on constructing the Korean version of LNNB-C and the cultural differences between Korean and American children in performing LNNB-C were discussed.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.88-88
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• 2003

• Journal of the Korean Arthroscopy Society
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• v.9 no.1
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• pp.1-8
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• 2005

• Electric Engineers Magazine
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• v.189 no.5
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• pp.32-37
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• 1998

전력용변압기에는 사선상태에서 조작하는 NLTC와 LTC Changer 또는 OLTC의 두 종류가 사용된다. NLTC의 구조는 사선상태에서만 조작되도록 만들어졌기 때문에 그렇지 않을 경우 기기수명의 단축과 함께 기기에 심한 손상이 발생하며 인명의 손상이 발생한다.

• Computational Structural Engineering
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• v.23 no.5
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• pp.34-41
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• 2010