• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 추계학술대회논문집
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• pp.797-801
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• 2003

This paper has the object of investigating natural frequencies of opening thick plates on Pasternak foundation by means of finite element method and providing Kinematic design data for mat of building structures. Vibration analysis that opening plate subjected to In-plane stress is presented in this paper. Finite element analysis of rectangular opening plate is done by use of rectangular finite element with 8-nodes. In order to analysis plate which is supported on Pasternak foundation, the Winkler foundation parameter is varied with 0, 10, 102, 103 and the shear foundation parameter is 0, 5, 10, 15. The ratio of In-plane force to critical load is applied as 0.2, 0.8, respectively. This paper analyzed varying opening Position and opening size.

• 한국산업정보학회논문지
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• 제3권1호
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• pp.49-65
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• 1998

The trend toward globalization and competitive advantage is increasing the importance of international data communication . The more companies attempt to be globalized and competitive, the more critical the problems of the computer networks are. To improve computer networks in the business world, it is believed that the network shoud be approached from the viewpoint of service quality : we need to understand what network quality means to network users, those who use the network. The purpose of this study is to develop a dimension that captures the aspects of network quality that are important to network users. Many articles show that speed is very important factor in network systems. But the more important thing is that speed is just one of the factors contributing to network quality. It is suggested that a quality network meet nine dimensions : (1) speed (2) accessibility (3) connectivity (4) security (5) compatibility, (6) government restrictions (7) complexity (8) sustainability and (9) sharability.

• Neonatal Medicine
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• 제16권2호
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• pp.131-136
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• 2009

Preterm infants are frequently discharged from the hospital with growth retardation. Given the potentially lifelong effects of growth impairmnet during a critical time of development, considerable effort should be focused on improving growth after discharge. Growth monitoring must be based on regular measurements of weight, length, and head circumference to identify those preterm infants with poor growth that may need additional nutritional support. Although prior studies vary in design and the intervention used, the evidence supports the use of fortified formulas in formula-fed preterm infants after discharge. The situation for infants fed human milk is much less clear, it seems prudent to concentrate our efforts on the encouragement of breast-feeding in this population. Catch up growth may have many benefits, and may lead to improved development. However, its long-term metabolic consequences are currently unclear. Understanding the optimal means of providing nutrition after discharge is an ongoing process.

• 한국소음진동공학회논문집
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• 제19권12호
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• pp.1296-1305
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• 2009

This paper has the object of investigating dynamic stability of stiffened tapered thick plate with concentrated mass on Pasternak foundation by means of finite element method and providing kinematic design data for mat of building structures. Finite element analysis of stiffened tapered thick plate is done by use of rectangular finite element with 8-nodes. In order to analysis plate which is supported on Pasternak foundation, the Winkler foundation parameter is varied with 10, 100, 1000 and the shear foundation parameter is 5, 10, concentrated mass is $0.25m_c$, $1.0m_c$, tapered ratio is 0.25, 0.5. The ratio of In-plane force to critical load is applied as $0.4\sigma_{cr},\;0.6\sigma_{cr},\;0.8\sigma_{cr}$ respectively. This paper analyzed varying tapered ratio.

• 한국문헌정보학회지
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• 제33권2호
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• pp.90-90
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• 1999

The academic journal is a very important means for science communication, and it is critical for academic development. Most of Korean academic journals are not doing their fundamental roles because of the researchers' perception about their quality. A fundamental thing for Korean academic Journals to contribute effectively to science communication would be the effective evaluation on the journal. The purpose of this study is to develop an evaluation model for Korean academic Journals. This model will be effective for quality measurement, manifestation of the strength and weakness, and for the improvement of journal qualify. It was developed through analysis on evaluation activities of two institutions, and through interviews and surveys on Korean researchers.

• 대한수학교육학회지:학교수학
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• 제1권2호
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• pp.401-415
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• 1999

In this paper, 'relations of proportion are used in the introduction of function concept' in 7-first stage of 7th mathematics curriculum is focused. Under the assumption that above statement means dependence-centered view in the teaching of function, the contents of function In 7-first stage is interpreted. Some issues are critically contemplated, And, finally, statement of using relations of proportion in the introduction of function concept is interpreted as dependence-centered view in the teaching of function. Conclusions are as follows: (1) symbol y= f(x) is not inevitable. (2) Term 'codomain' must not be used. (3) Term 'range of x' and 'range of y' must be used. (4) Term 'independent variable' and 'dependent variable' must be used.

• 열처리공학회지
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• 제12권3호
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• pp.215-220
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• 1999

Rotary bending fatigue tests were carried out to investigate the artificial defect sensitivity of fatigue limit in annealed and austempered ductile irons. Artificial defect(hole, diameter${\leq}0.4mm$) machined on specimen surface did not bring about an obvious reduction of fatigue limit in austempered ductile iron as compared with annealed. As a result of investigation on $\sqrt{area}$ c which is the critical artificial defect size. $\sqrt{area}$ c of austempered ductile iron is larger than that of annealed. This means that the crack initiation at artificial defect in austempered ductile iron is more difficult in comparison with annealed. In case that the $\sqrt{area}$ c of artificial defect and graphite nodule are same, the rate of crack initiation for graphite nodule is higher than that of artificial defect.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2006년도 춘계학술논문 발표대회 제6권1호
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• pp.97-100
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• 2006

This paper report the result of the investigation on the properties of drying shrinkage for alkali-activated slag mortar in different relative humidity Commonly we know that drying shrinkage means lost more moisture but the mechanism of drying shrinkage of alkali activated slag mortar is not entirely due to the quantity of weight loss of water from mortar. pore size distribution and the calcium silicate hydrate gel characteristics have a critical influence on the magnitude of drying shringkage to alkali activated slag mortar. For this investigation, Ca(OH)2, Na2SiO4 were as alkali activator with 5 dosages(6%, 9%, 12%, 15%, 20%) and curing condition were three different relative humidity(35%, 65%, 95%) at $20{\pm}3^{\circ}C$

• 대한가정학회지
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• 제19권4호
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• pp.9-15
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• 1981

damages of cotton cloth and characteristics of fabroid degradation were studied by Chaetomium globosum and Aspergillus niger which presupposed as powerful erosive fungi to cellulose fiber by means of tensile strength. The results obtained are as follows: 1. the growth(rate) of fungi in malt extract agar was superior to potato agar for two weeks. 2. Chaetomium globosum showed mostly severe damage t the cotton cloth in malt extract agar media at pH 4.5. 3. Tensile strength was reduced with time by Aspergillus niger-coenzyme and Chaetomium globosum-coenzyme reaction. In comparison with Chaetomium globosum and Aspergillus niger, the former weaken tensile strength about 15.8% and the latter enfeebled 10.0% after 124 hours. 4. after 30 days the breeding of fungi in pH 4.5 malt extract agar media, critical damage of cotton cloth was observe, I. e., 92.4% damage by chaetomium globosum and 74.9% lose by aspergillus nige respectively.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.171-173
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• 2001

Conventional potential concept does not allow different currents before and after the electric load. Experimental examples in case of bioloads show a lot of different currents before and after the bioload, which means that the true potential concept is not the conventional concept from Coulomb attraction energy but the new concept from Gibb's free energy. Gibb's free energy is a kind of potential heat energies and also they are rotating electromagnetic waves. We might think that electric current is not a flow of electrons but a flow of rotating electromagnetic waves, which induces electrons' vibrations. A new measuring method for integral electrical power is suggested for the new Gibb's free energy concept.