• Analytical Science and Technology
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• v.5 no.1
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• pp.1-5
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• 1992

The adsorption amount of petroleum oil on XAD-4, XAD-7 and replacement adsorbents as rice bran, rice straw and sawdust were studied by using batch method measured in the optimum adsorption condition. The adsorption capacity of rice bran and rice straw of petroleum oil were excellent as well as adsorption ability about 50% of XAD resins and adsorption capacity of their replacement adsorbents were increased with optimum condition that pyrolysis time was 30 min. at $200^{\circ}C$. Adsorption ability of sawdust was very weak on the 30% MeOH aqueous medium but adsorption ability was range of about 50% of XAD resin's adsorption capacity on the 0.5M NaCl aqueous medium. Adsorption ability of rice bran and rice straw showed the same adsorption capacity even if difference external structure. Therefore, showing that rice bran and rice straw were have to good adsorption ability as replacement adsorbent for XAD resins.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.3
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• pp.356-363
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• 2017

Blast furnace slag(BFS) is a by-product generated during the manufacture of pig ion, and is divided into water-cooled slag(WS) and air-cooled slag(AS) by the coking method of BFS. In this study, concrete specimens with ternary binders were produced at the various replacement levels of cement by AS. Various mechanical properties of concrete, such as compressive and split tensile strengths, absorption and water permeable pore, were measured. In addition, the chloride ions penetration resistance and carbonation resistance were tested to evaluate the durability of concrete incorporating AS. The experimental data indicated that the use of AS up to a maximum of 10% replacement level enhanced the concrete performance. However, a higher replacement of AS exhibited poor mechanical properties and concrete durability.

• International Journal of Oral Biology
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• v.35 no.1
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• pp.1-5
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• 2010

Human fibroblasts that maintain the structural integrity of connective tissues by secreting precursors of the extracellular matrix are typically cultured with serum. However, there are potential disadvantages of the use of serum including unnatural interactions between the cells and the potential for exposure to animal pathogens. To prevent the possible influence of serum on fibroblast cultures, we devised a serum-free growth method and present in vitro data that demonstrate its suitability for growing porcine fetal fibroblasts. These cells were grown under four different culture conditions: no serum (negative control), 10% fetal bovine serum (FBS, positive control), 10% knockout serum replacement (KSR) and 20% KSR in the medium. The proliferation rates and viabilities of the cells were investigated by counting the number of cells and trypan blue staining, respectively. The 10% FBS group showed the largest increase in the total number of cells ($1.09\;{\times}\;10^5\;cells/ml$). In terms of the rate of viable cells, the results from the KSR supplementation groups (20% KSR:64.7%; 10% KSR: 80.6%) were similar to those from the 10% FBS group (68.5%). Moreover, supplementation with either 10% ($3.0\;{\times}\;10^4\;cells/ml$) or 20% KSR ($4.8\;{\times}\;10^4\;cells/ml$) produced similar cell growth rates. In conclusion, although KSR supplementation produces a lower cell proliferation rate than FBS, this growth condition is more effective for obtaining an appropriate number of viable porcine fetal fibroblasts in culture. Using KSR in fibroblast culture medium is thus a viable alternative to FBS.

• Journal of the Korea Concrete Institute
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• v.28 no.4
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• pp.427-434
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• 2016

The purpose of this study is to propose a mixture proportioning approach based on the replacement level of natural sand for reducing $CO_2$ emissions from artificial lightweight aggregate concrete(LWAC) production. To assess the effect of natural sand on the reduction of $CO_2$ emissions and compressive strength of LWAC, a total of 379 specimens compiled from different sources were analyzed. Based on the non-linear regression analysis using the database and the previous mixture proportioning method proposed by Yang et al., simple equations were derived to determine the concrete mixture proportioning and the replacement level of natural sand for achieving the targeted performances(compressive strength, initial slump, air content, and $CO_2$ reduction ratio) of concrete. Furthermore, the proposed equations are practically applicable to straightforward determination of the $CO_2$ emissions from the provided mixture proportions of LWAC.

• Journal of Korean Critical Care Nursing
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• v.9 no.1
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• pp.40-50
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• 2016

Purpose: Continuous renal replacement therapy (CRRT) has become the preferred dialysis method to support critically ill children and neonates with acute kidney injury. Using CRRT on neonates has increased, but reports about experience are limited. The aim of this study is to describe the clinical application, outcomes, and complications of CRRT in children and neonates. Methods: A retrospective review was performed in 135 children and 36 neonates who underwent CRRT at a tertiary hospital from 2008 to 2015. Results: At the initiation of CRRT, the median age of children was 72 months and the corrected age of neonates was 37.1 weeks. Median body weight of neonates was 3.2 kg. In neonates, initial degree of fluid overload [FO%], blood flow rate [BFR] and ultrafiltration rate [UFR] rate during CRRT were higher than in children. Median real time of CRRT was 90.5 and 53.5 hours in children and neonates, respectively. Downtime of CRRT was 0.7 and 1.3 hours/day. Median mortality rates (44.4% vs.47.2%) and complication rates were similar between the groups. Conclusion: CRRT can be used for a wide range of critically ill children and neonates. Different application methods of CRRT can contribute to increased survival of neonates.

• Journal of the Korean Ceramic Society
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• v.42 no.2 s.273
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• pp.99-103
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• 2005

Nowadays, large amount of waste pottery and porcelain annually are produced. It is needed that they are used as recycled materials in order to prevent environmental pollution and gain economic profits. Therefore, the purpose of this study is to present the method of utilizing the recycled aggregates that are obtained from waste pottery and porcelain as the concrete aggregate. The qualities of the recycled aggregate were compared with those of the crushed aggregate through measuring their physical properties. The test results showed that the replacement of crushed aggregate by recycled aggregate at the levels $10\%,\;20\%$, and $30\%$ had little effect on the compressive strength of the concretes, but higher levels of replacement reduced the compressive strength. Increment of the replacement of recycled aggregate caused increase in absorption ratio. As a conclusion, norman strength recycled aggregate concretes can be produced using less than $30\%$ of recycled aggregate.

• Journal of Korean Critical Care Nursing
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• v.2 no.1
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• pp.58-68
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• 2009

Purpose: The treatment effects and operation status of continuous renal replacement therapy (CRRT) for acute renal failure patients have been investigated. Method: Two expert nurses reviewed the records of 731 patients undergoing CRRT in an intensive care unit of a general hospital from Jan. 2002 to Dec. 2006 with the CRRT assessment sheet and situation sheet developed for this study. Results: The number of patients received CRRT increased from 90 in 2002 to 194 in 2006. The most common indication for CRRT was azotemia (40.0%). Before CRRT treatment, patients were 78.6 ($\pm55.5$) of BUN value and 5.0 ($\pm3.2$) of Cr. value. The standard values of BUN and Cr. were lowered. Compared the survival group with the death group, there were significant differences among the medical departments and the main diagnosis group. Their BUN and creatinine value, APACHE II score, mean blood pressure, and oliguria were significantly different (p<0.05). Conclusion: This survey demonstrates a trend that patients receiving CRRT has been increased. We suggest further studies are needed in some hospitals in order to generalize the results and to find how CRRT treatment affects patient’s survival and death rate.

• Applied Chemistry for Engineering
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• v.23 no.4
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• pp.409-415
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• 2012

To recycle the steel slag as manufactured composite materials of polymer concretes, we used the atomizing method to make round aggregates from steel slag, which is treated as industrial wastes. A round rapid-cooled steel slag was used to replace fine aggregate (river sand) or coarse aggregate (crushed aggregate), depending on the grain size. To examine general physical properties of polymer concrete composites manufactured from rapid-cooled steel slag, the polymer concrete specimen with various proportions depending on the addition ratio of polymer binder and replacement ratio of rapid-cooled steel slag were manufactured. In the result of the tests, the mechanical strength of the specimen made by replacing the optimum amount of rapid-cooled steel slag increased notably (maximum compressive strength 117.1 MPa), and the use of polymer binder, which had the most impact on the production cost of polymer concrete composites, could be remarkably reduced. However, the mechanical strength of the specimen was markedly reduced in hot water resistance test of polymer concrete composite.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.3
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• pp.1-9
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• 2015

Due to the increasing number of deteriorated bridges worldwide, the importance of maintenance and replacement of existing bridges are being emphasized. Cast-in-place concrete deck which is mainly applied to deck replacement of existing bridges have problems such as deterioration concerns by initial crack, labor cost increase, difficulties of maintenance and replacement, construction time increase, and indirect cost increase by traffic congestion. On the contrary, a precast concrete deck is considered as an effective alternative because of its quality assurance and accelerated construction. The connection method ensuring the required strength and durability is especially important, because the connection part of the precast concrete deck is vulnerable to cracks and leakage. Therefore, this study proposes precast bridge decks with ribbed connection which are more improved than existing bridge deck joints, and flexural performance is verified through various parameter tests.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.4
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• pp.456-462
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• 2014

In this paper, we develop a facility management system which provides fault effect and replacement alarm function of each component for supporting effective maintenance of facility. To do this, we use weighting method to each component, calculate importance of each component, and make them to hierarchy structure using bill of materials of facility. Also, we draw fault cause and fault effect of components based on failure modes effects and criticality analysis, and define criteria of severity, occurrence and detection to get risk priority number. To apply these concepts, we develop and test the facility management system to verify its practicality. In the future, we expect the developed system to apply many domains such as maintenance of ship and offshore plant.