• Journal of the Korean Society for Nondestructive Testing
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• v.22 no.1
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• pp.65-73
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• 2002

Artificial aging was performed to simulate the microstructural degradation in 2.25Cr-1Mo steel arising from long time exposure at $540^{\circ}C$. Microstructural analysis (mean equivalent size, number of carbides per unit area) and measurement of mechanical properties(UTS, Vickers hardness) and magnetic properties(coercivity, remanence) were performed. By comparing these results, the relationship between magnetic properties and microstructural changes with artificial aging was clarified. The carbides were classified as rod, globular and acicular type in terms of morphology. The fine acicular carbides were found to diminish drastically in the initial stage of aging. The magnetic coercivity and remanence were observed to decrease rapidly in the initial about 920 hours of aging time and then decrease slowly afterwards. Linear correlations between the mechanical properties and magnetic properties such as correlations remanence were found.

• Current Research on Agriculture and Life Sciences
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• v.4
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• pp.7-11
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• 1986

Nine Korean local cultivars and 34 PI lines of pepper were tested for resistance to anthracnose (Colletotrichum dematium). Red ripe fruits were harvested, punctured and inoculated by spraying and dropping a conidial suspension of Colletotrichum dematium. Resistance was evaluated by measuring the diameter of ripe rot lesions developed on and around the puncture. The results obtained are as follows : 1. PI 201232, PI 224451, PI 257044, PI 257119, PI 257099, PI 224433, PI 244668, PI 257102, PI 173877, Namji, Cheongryong, and Seodong were the least diseased and considered to be resistant. 2. PI 241670, PI 244670, and PI 224423 were the most diseased and considered to be susceptible. 3. Others were in between the two extremes and considered to be intermediate.

• The Journal of the Petrological Society of Korea
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• v.25 no.3
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• pp.283-298
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• 2016

Sangumburi crater, designated as Natural Monument No. 63, recognized as a maar, but precise geological mapping and geological characteristics in the field indicate that Sangumburi crater is a pit crater. Two stages of volcanic activities created Sangumburi pit crater. Lava flow (aphanitic pyroxene basalt I) and associated pyroclastic deposit (pyroclast I), composed of ash and lapilli, were formed at the stage 1. In the stage 2, lava flow (feldspar olivine basalt) was overlain by lava flow (aphanitic pyroxene basalt II) and associated pyroclastic deposit (pyroclast II), composed of agglomerate. Sangumburi pit crater formed at $0.073{\pm}0.036Ma$, determined by Ar-Ar age dating for the feldspar olivine basalt at the stage 2. It is not clear the preferred migration direction of subsurface magma after Sangumburi pit crater formed.

• Journal of Korean Clinical Nursing Research
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• v.25 no.1
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• pp.91-97
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• 2019

Purpose: The purpose of this study was to investigate hemato-oncology patients' discomfort and bleeding in relation to the bedrest time after bone marrow examination. Methods: A descriptive correlational study was conducted. The data were collected using self- report questionnaire from total of 131 patients who underwent bone marrow examination from January 2017 to September 2017. Data were analyzed with descriptive statistics, Wilcoxon Signed-rank test, McNemar's test and logistic regression. Results: The level of discomfort after 4 hours of bedrest was significantly higher when compared to 2 hours of bedrest(p<.001). The occurrence of bleeding after 2 hours of bedrest was significantly higher than 4 hours of bedrest(p<.001), however the degree of bleeding was slight. No bleeding occurred in 84% of the patients after 2 hours of bedrest. Conclusion: The results of this study demonstrated that shortening the bed rest time after bone marrow examination was helpful in improving the patient's well-being. Bedrest time could be shortened according to the site of bone marrow examination and patient's condition.

• Journal of Korean Academy of Nursing
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• v.51 no.4
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• pp.414-429
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• 2021

Purpose: This systematic review and meta-analysis analyzed the effects of 2% chlorhexidine bathing on the incidence of hospital-acquired infection (HAI) and multidrug-resistant organisms (MDRO) in adult intensive care units. Methods: PubMed, CINAHL, Cochrane library, and RISS database were systematically searched, and 12 randomized studies were included in the analysis. Comprehensive Meta-Analysis version 3.0 was used to calculate the effect size using the odds ratio (OR) and a 95% confidence interval (CI). Subgroup analysis was performed according to the specific infection and intervention types. Results: In general, 2% chlorhexidine bathing has a significant effect on the incidence of HAI (OR, 0.59; 95% CI, 0.40~0.86) and MDRO (OR, 0.52; 95% CI, 0.34~0.79). Subgroup analyses show 2% chlorhexidine bathing is effective in bloodstream infections (OR, 0.51; 95% CI, 0.39~0.66) but not for urinary tract infections, ventilator-associated pneumonia infections, and Clostridium difficile infections. Moreover, 2% chlorhexidine bathing alone or its combination with other interventions has a significant effect on the incidence of HAI and MDRO (OR, 0.59; 95% CI, 0.38~0.92). Conclusion: This meta-analysis reveals that 2% chlorhexidine bathing significantly reduces the incidence of HAI and MDRO in intensive care units. The effect of 2% chlorhexidine bathing on pediatric patients or patients at general wards should be further assessed as a cost-effective intervention for infection control.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.11
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• pp.1043-1049
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• 2005

The purpose of this study is to improve indoor air quality of the barracks which have been changed from floor-type living barracks to bed-type living barracks since 2003. Therefore, the ventilation rates of newly constructed two type barracks were simulated with the various building materials including VOCs and HCHO components. And indoor air quality of two type living barracks was measured by the field experiments. With these steps, the measures for upgrading indoor air quality depending on building material types and ventilation rate are suggested.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.8 no.4
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• pp.451-462
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• 1996

In this study, which focuses on ice storage, a fundamental study in cooling and solidification was performed, including the interesting phenomena of density inversion, supercooling and dendritic ice. A numerical study was performed for natural convection and ice formation considering existence of subcooling and dendritic ice were analyzed numerically by using finite difference method and boundary fixing method. In the mesh, the solid fraction was introduced with adding as a term to the energy conservation equation. A flow in the dendrite was modelled as a flow in a porous medium, and the momentum conservation equation was modified to incorporate resistance forces involved in flows through porous media. A numerical solution of the time dependencies of dendrite area and dense ice front was successfully obtained, and the numerical results were good agreement with experimental results. Based on this methodology, a discussion was made of phenomena and characteristics of cooling and freezing processes under various conditions.

• Research in Plant Disease
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• v.6 no.1
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• pp.15-18
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• 2000

A new bacterial disease was found on leaves of Kalanchoe blossfeldiana plant grown under vinyl-house condition in winter of 1998 in Taejeon. the first symptoms of the disease are the appearance of the water-soaked and light brown spots. Later they become soft rot with brown color. Causal bacteria were isolated from diseased tissues and the same symptoms as the natural infection were developed on Kalanchoe blossfeldiana leaves by needle-prick inoculation. The causal bacterium was identified Erwinia hervicola by its bacteriological characteristics. This is the first reported of this bacterium to occur on kalanchoe blossfeldiana plant in Korea. Therefore, we proposed to name the diseases as \"bacterial soft rot of Kalanchoe blossfeldiana\" by E. herbiocla.

• Microbiology and Biotechnology Letters
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• v.17 no.2
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• pp.121-125
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• 1989

Actinomycetes GF 155-2, which produced an extracellular pepsin inhibitor, was isolated from soil samples. Optimal conditions of inhibitor production by flask-shacking culture were 2% glucose, 0.7% polypeptone, initial pH 1.0, culture time 60 hours and temperature 30%. Effect of in-organic salts was not observed. About 5mg of colorless crystalline inhibitor was obtained from 5L culture broth in jar tormentor by means of ammonium sulfate precipitation, methanol extraction, and column chromatographies on Amberlite IR-120, XAD-2 and silicagel 60.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05c
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• pp.182-187
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• 1996

원자로 압력용기강의 품질 열처리인 ？칭과 템퍼링 중간에 페라이트와 오스테나이트가 공존하는 2상영역에서 열처리를 행함으로써 인성을 향상시키는 제조공정을 개발하였다. 710~74$0^{\circ}C$에서 4~8시간 동안 2상영역 열처리를 추가하면 기존 열처리 과정에 비하여 상온 충격인성이 크게 증가하였다. 상온 충격인성과 두께를 고려하여 결정한 최적 조건안 7$25^{\circ}C$에서 6시간 동안 2상영역 열처리를 하면 최대 흡수 에너지가 30~50% 증가하고, 천이 온도가 약 l$0^{\circ}C$ 감소하였다. 2상영역에서 형성된 침상 오스테나이트는 냉각 중에 하부 베이나이트 또는 마르텐사이트로 변태하여 템퍼드 베이나이트와 복합조직을 이루므로 균열진전을 억제하여 충격인성이 향상되었다. 2상영역 열처리 온도가 높거나 시간이 길면 오스테나이트의 체적 분율이 증가하거나 조대화가 일어나 균열진전억제 효과는 저하되었다.