• Journal of the Korean Ceramic Society
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• v.46 no.4
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• pp.365-371
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• 2009

It is well known that the properties of concrete such as the compressive strength, water permeability, water tightness and durability are affected by micro-structure in hardened cement paste. Especially, for durability of concrete, watertightness of cementitious materials is the most critical property among various properties. Recently, many types of materials as organic and/or inorganic materials are used for watertightness of concrete. In this study, The effect of Stearic Acid at $0.5\;wt%{\sim}3.0\;wt%$ adding ratios on the hydration and watertightness property of cement were investigated. And we also discussed the changing of microstructure in hardened cement paste by addition of Stearic Acid. Cement paste with Stearic Acid showed improvement of watertightness by reducing of cement total pore volume and decomposition of Stearic Acid.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2003.11a
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• pp.83-87
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• 2003

In recent days, IAQ(Indoor Air Quality) is regarded as one of the most important environmental factors as well as thermal and acoustic comfort. Various architectural materials are applied and air-tightness of the building is more strengthening to save energy consumption. This is why the air quality of the newly built houses became worse. In this study, contaminants(CO, CO$_2$, Radon, TVOCs, HCHO) density was measured in a newly built house and evaluation was carried out by ASHRAE and EPA Standards. As a result, CO, CO$_2$, TSP and Radon density of the newly built house was in a range of ASHRAE and EPA Standards, but it turned out TVOCs and HCHO density exceeds almost 3${\sim}$5 times in comparison with that of ASHRAE and EPA Standards.

• Annals of Clinical Neurophysiology
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• v.7 no.1
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• pp.46-48
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• 2005

Eosinophilic fasciitis (EF), also known as Shulman syndrome, is an inflammatory disorder of unknown etiology. It usually presents with pain, swelling, and tenderness of the proximal aspect of the limbs, chest, or neck, with subsequent induration of the skin and subcutaneous tissues, in association with peripheral eosinophilia. EF is differentiated from scleroderma by the pattern of skin involvement and non-involvement of muscle. We report a case of progressive EF presented with tightness and stiffness in all limbs.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.13 no.3
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• pp.215-223
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• 2013

In this paper, we present some results on weak laws of large numbers for weighted sums of fuzzy random variables taking values in the space of normal and upper-semicontinuous fuzzy sets with compact support in a separable real Banach space. First, we give weak laws of large numbers for weighted sums of strong-compactly uniformly integrable fuzzy random variables. Then, we consider the case that the weighted averages of expectations of fuzzy random variables converge. Finally, weak laws of large numbers for weighted sums of strongly tight or identically distributed fuzzy random variables are obtained as corollaries.

• Journal of Chest Surgery
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• v.44 no.3
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• pp.247-249
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• 2011

We report a case of pseudo-pseudoaneurysm, which is a very rare complication of myocardial infarction. A 69-year-old man was admitted to our clinic with chest tightness and dyspnea. He had undergone aortic valve replacement with a pericardial bioprosthetic valve, ring mitral annuloplasty, and reconstruction of an aortic annular defect due to infective endocarditis with bovine pericardium 4 years prior. Echocardiography and computed tomography showed pericardial effusion and a 16-mm cavity at the anterolateral wall of the left ventricle. Magnetic resonance imaging suggested either pseudo-pseudoaneurysm or myocardial abscess. We successfully repaired the myocardial defect using a patch made from a vascular graft with pledgeted horizontal mattress sutures under cardiopulmonary bypass.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.25 no.6
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• pp.434-439
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• 2016

Optical fiber splice closure serves to protect connection parts from external environment. Moreover, it functions as a connection, junction, and distribution in diverse surroundings such as aerial, underground, duct, and pole. In this research, first, the optical fiber splice closure, its configuration, and the design problem were briefly investigated. Second, the design and application for in-line cable closure were studied to satisfy its construction and technical features. The injection molding conditions and optimal design were conducted to save time and cost during the manufacturing process. Third, methods to minimize loss via of optical fiber cable while strongly fixing optical fiber cable with optical cable holder to prevent fracture were researched, and tests such as perfect air tightness and mechanical and environmental performance were conducted.

• Korean Journal of Materials Research
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• v.23 no.12
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• pp.687-694
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• 2013

This study was performed with an aim to improve the early-age strength of concrete containing fly ash, which is known to increase the long-age strength of concrete, reduce drying shrinkage, and enhance water tightness. The composition was partially substituted with calcium sulfoaluminate (CSA), from which ettringite is actively produced, in the early stages of hydration to verify its effect on improving the early-age strength and to determine the optimal mixing ratio. For this purpose, up to 30 % of the cement weight was substituted with fly ash, and the amount of CSA substitution was 8% of the fly ash weight. The mixtures were then fabricated into concrete specimens for compressive strength measurement and analysis of the correlation between the hydration products and the compressive strength.

• Tunnel and Underground Space
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• v.8 no.2
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• pp.79-86
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• 1998

This study was performed to suggest to suggest suitable design conditions of water curtain system through analysis on pressure down in boreholes by hydraulic tests carried out I construction fields for underground oil storages. The influence by hydraulic conductivities of rock mass around boreholes on pressure down in boreholes was analysed. The relationship between array of boreholes and their pressure down was also analysed. Groundwater flow analysis on crude oil and LPG storages was carried out to evaluate results of field tests and to investigate distribution of hydraulic gradient in rock mass around cavern using finite difference method. As the results, hydraulic tests showed that pressure down in boreholes was inverse proportional to the hydraulic conductivity of surrounding rock mass. The rate of pressure down of boreholes was not influenced by water curtain system more than 20m over cavern and was proportional to installation interval of boreholes. The hydraulic gradient in rock mass around cavern was proportional to distance and interval of boreholes and its value was not satisfactory to oil tightness condition in case of no water curtain system.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.25 no.2
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• pp.79-81
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• 2014

Spasmodic dysphonia (SD) is a chronic, focal, speech-induced, action-specific dystonia, resulting strained voice. Muscle tension dysphonia (MTD) may also result in a strangled, strained voice quality, usually as a result of compensation for underlying laryngeal disease such as glottal insufficiency. Patients with SD and MTD were suffered from the severely limiting people's communication, especially via telephone and in noisy backgrounds. SD is usually of the adductor type characterized by glottic contractions causing tightness and voice breaks, which is difficult to distinguish from MTD. In this review article, we present the characteritics and management of SD and MTD.

• Journal of the Korean housing association
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• v.19 no.1
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• pp.49-55
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• 2008

Recently, much attention has been paid to the problem such as sick building syndrome, which caused by the indoor air pollutant. Volatile Organic Compounds $(VOC_s)$ and formaldehyde have been considered as one of the main reason that causes indoor air pollutant. This study is for introducing and designing thermal performance of super energy saving building by conducting $VOC_s$ and formaldehyde concentration in the 3Liter house. The results of the measurement for 10 months showed that $VOC_s$ and formaldehyde decreased until the guideline concentration. It took about 7 months, and it appeared right after new construction. However, their levels were showed higher concentration in comparison with the ordinary residential houses (apartment house). The main difference of between newly built 3Liter house and ordinary apartment is their air changes, which are 0.67/h for 3Liter house and 4.0/h for the apartment.