• Journal of The Korean Association For Science Education
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• v.11 no.1
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• pp.117-126
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• 1991

The new movement in science education in America and Europe has been heavilly oriented into technological and soceital aspect of science since 1970. However, this spirit has not been well informed in Korea and not adapted in science education. This paper aimed to arouse Korean science educators attention to everyday situation as a science education context. In this paper, the discipline centered science education was briefly reviewed and problems related to the philosophy was pointed out. At the same time the researcher introduced STS context as a science education objective, and elaborated the three elements(physical situation, technological situation. and societal situation) of the context. In the paper, the advantages of the use of everyday context in science education were examined. THe advantages were analysed in terms of the nature of science, learning psychology, integrated science, and societal aspect of science education. The paper also suggested the criteria to select teaching materials from STS context. The suggested criteria were the degree of science concepts involvement, frequency of experience, strength of experience, and possibility of direct experience.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.214-219
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• 2008

Recently, railway has been pointed to the efficiency of transportation, rapid transit, and comfortable train ride. In the case of domestic situation, both rapid transit railway and existing railway have been operated in higher speed and the construction of railway near the city building has been increased as well. Because of the rapid transit system and heavy railway, the noise and vibration of railway has been increased so that the strong standards in terms of environmental matter should be required. Therefore, the solution to avoid environmental matters becomes one of the most important factor in constructing railway. In this study, floating slab system which is one of the solution to avoid noise and vibration in railway has been introduced, and the foreign technology and the trend of this business has been investigated. In addition, the method of conceptual design and construction of floating slab system according to the isolator has been introduced.

• Journal of the Korean Institute of Intelligent Systems
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• v.18 no.1
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• pp.145-149
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• 2008

The similarity measure is constructed for non-convex fuzzy membership function using well known Hamming distance measure. Comparison with convex fuzzy membership function is carried out, furthermore characteristic analysis for non-convex function are also illustrated. Proposed similarity measure is proved and the usefulness is verified through example. In example, usefulness of proposed similarity is pointed out.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.1057-1064
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• 2009

Since the global warming causes debris flow damage has increased in Kangwon Area, Sediment control dam have increasingly founded to protect the damage. In spite of the realities design methods are well not established to determine type of the dam, design parameters and maintenance. Through comparison for design methods to sediment control dam in Korea, it raised some points to improve to correspond with realities. In addition, it pointed that some issues for the sediment control dams in Kangwon Area. Those are shown that unclear positions of the dams, unremoval of sediment, occurrence of seepage under the dams and uninstallation of roads to remove sediment. In addition, the countermeasure for the issues are proposed.

• Structural Engineering and Mechanics
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• v.61 no.1
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• pp.31-47
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• 2017

As a relatively new type of multi-layered rubber-based seismic isolators, fiber-reinforced elastomeric isolators (FREIs) are composed of several thin rubber layers reinforced with flexible fiber sheets. Limited analytical studies in literature have pointed out that "warping" (distortion) of reinforcing sheets has significant influence on buckling behavior of FREIs. However, none of these studies, to the best knowledge of authors, has investigated their warping behavior, thoroughly. This study aims to investigate, in detail, the warping behavior of strip-shaped FREIs by deriving advanced analytical solutions without utilizing the commonly used "pressure", incompressibility, inextensibility and the "linear axial displacement variation through the thickness" assumptions. Studies show that the warping behavior of FREIs mainly depends on the (i) aspect ratio (shape factor) of the interior elastomer layers, (ii) Poisson's ratio of the elastomer and (iii) extensibility of the fiber sheets. The basic assumptions of the "pressure" method as well as the commonly used incompressibility assumption are valid only for isolators with relatively large shape factors, strictly incompressible elastomeric material and nearly inextensible fiber reinforcement.

• Journal of Applied Reliability
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• v.12 no.1
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• pp.25-33
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• 2012

As to display products are made slim, the diameter of aluminum electrolytic capacitor is smaller and the length is longer to be fitted in. These small diameter and long length are pointed as the disadvantageous design factors of the capacitor's life cycle. So, the most electronic makers want to use proven capacitors (or well-known) to secure reliability of the electric products. In this study, we carried out the comparison analysis with two domestic capacitors and one foreign made capacitor. We designated separators, rubber breather and debris as the main factors that effect on the lifetime of capacitors. From the comparison results, we suggested the improvement points of the aluminum electrolytic capacitor.

• KDI Journal of Economic Policy
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• v.24 no.2
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• pp.53-82
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• 2002

Earlier papers, regarding this topic, have shown that the optimal environmental tax rate under the second best situation typically smaller than that under the first best world, the well known Pigouvian tax. This paper casts a doubt on the generality of this result, since the conclusion was derived from the models which employed rather strict assumptions on the utility function, which is homothetic and separable. This paper, with simple-static CGE model, shows that the result of earlier studies is sensitive to the assumption on the utility function. According to the simulation results, as previous studies pointed out, if the utility function is assumed to be homothetic, the optimal environmental tax rate is smaller than the Pigouvian tax. In contrast, if certain type of non-homotheticity is allowed, the optimal environmental tax rate could be greater than the Pigouvian tax. The results of this simulation also imply that the enlargement of environmental tax base could enhance the efficiency of overall tax system. Hence, there will be a less burden to share for the tax authority from the policy change.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.2
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• pp.96-105
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• 2004

Throughout the modernization which was dominated by development theory in Korea, land use planning for housing tended to spoil the environment. Numerous studies, however, pointed out the problem of this development-led planning and there was a broader consensus that the past planning was part of the environmental problem of inner city. These observations changed the development-led planning into the environmental friendly development planning. In particular, Seoul Metropolitan Government held the international planning competition to develop 'Sangam' as an environment friendly residential area. With this plan 'Sangam' would be the sustainable residential area with the harmony of nature, human and technology. Furthermore it would be the outset of the long-term plan to develop 'Seoul' as a 'gate-city, an 'information-city' and an 'eco-city'. To do this, it needs especially the planners' and the constructors' constant concerns and efforts as well as the citizen's participation.

• Communications of the Korean Mathematical Society
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• v.16 no.2
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• pp.319-332
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• 2001

The main object of this paper is first to give tow contiguous analogues of a well-known hypergeometric summation formula for $_2$F$_1$(1/2). We then apply each of these analogues with a view to evaluating the sums of several classes of series in terms of Psi(or Digamma) and the Zeta functions. Relevant connections of the series identities presented here with those given elsewhere are also pointed out.

• Korean Journal of Poultry Science
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• v.7 no.2
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• pp.4-17
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• 1980

This is to review from the existing literatures the various methods of determination, problems involved in the determination of metabolizable energy(ME) values of poultry feedstuffs that is the most widely used energy term in poultry nutrition. An attempt will also be made to introduce the newly developed determination method of ME by Sibbald and his associates. It was found that conventional methods of ME measurements such as total collection method and indicator method require a great deal of labor and time. It should also be pointed out that these methods have some technical problems as well. Experimental evidences indicate that the ME content of feedstuffs may be affected by breed, age, substitution level of basal diet, kind of basal diet, methods of chemical analysis and chemical composition of experimental diet. Standard procedures and technical advantages of newly developed method of "True Metabolizable Energy" system are fully described.