• The Mathematical Education
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• v.51 no.2
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• pp.145-160
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• 2012

Prospective teachers need to have an opportunity to critically examine their initial perception with regard to effective mathematics instruction during the teacher education period. This study analyzed the perception in relation to good mathematics instruction by a total of 265 prospective teachers from four institutes for elementary teacher education using a survey. The results of this study showed that the pre-service teachers regarded learner, teaching and learning method, selection of content, and construction of curriculum as important for high-quality mathematics instruction. However, they revealed relatively low levels of agreement against the importance of instructional materials, classroom environment and atmosphere, and assessment. On the basis of teachers' perception on each element of effective mathematics instruction, this paper raises issues for discussion and includes some implications for teacher education.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2000.11a
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• pp.85.1-88
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• 2000

FRP has been used very much as high strength core materials for insulators because of its high strength and good insulation properties. In this study cantilever, tension and torsion stress were simulation along to the unidirection glass fiber. In addition, FRP was made by pultrusion method. This paper proposed the procedure of the finite element model updating and pretest using the commerical finite element code MSC.Nastran. To ehance the efficiency of experimental modal analysis, we proposed the process which is the selection of the locations and the number of measurement points for pre-test.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1373_1374
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• 2009

The PLS-II, the major upgrade program of the PLS (Pohang Light Source, a 2.5-GeV 3rd generation light source), is planned at the Pohang Accelerator Laboratory. Given the glaring lack of normative data regarding the PLS-II the major upgrade, this study can be seen as the first in a needed stream of research investigating selection by dual gun and dc electron gun. Usable electron gun can think method to use dual electron gun and method to prove energy by existing electron gun in energy increase. This article is concerned with the formal classification of used of pre-injector electron gun type of the DC and pulse. Design concept wishes to show contents that design for pulse type of power supply and DC type of electron gun.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.644-644
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• 2013

Graphene is a two-dimensional sp2 layer material. Despite the short history in the empirical synthesis of the graphene layers, the academic/industrial unique features have brought highly significant interest in research and development related to graphene-related materials. In particular, the electrical and optical performances have been targeted towards pre-existing microelectronicand emerging nanoelectronic applications. The graphene synthesis relies on a variety of processing factors, such as temperature, pressure, and gas ratios involving H2, CH4, and Ar, in addition to the inherent selection of copper substrates. The current work places its emphasis on the role of experimental factors in growing graphene thin films. The thermally-grown graphene layers are characterized using physical/chemical analyses, i.e., four point resistance measurements, Raman spectroscopy, and UV-Visible spectrophotometry. Ultimately, an optimization strategy is proposed in growing high-quality graphene layers well-controlled through empirical factors.

• Proceedings of the KSAR Conference
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• 2002.06a
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• pp.17-17
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• 2002

There are considerable reports that the expression of insulin-like growth factor-Ⅰ (IGF-Ⅰ) is related to ovarian regulation and oviductal development in poultry. Korean Native Ogol Chicken (KNOC) have been inbred to keep a pure line so that there has been limitation in the improvement of egg productivity by genetic studies. Therefore, this study was conducted to investigate the early egg productivity of KNOC pre-selected by IGF-Ⅰ expression. (omitted)

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2009.11a
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• pp.51-52
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• 2009

Recently, several industrial countries using the fission energy have given attention to the Gen-IV SFR (sodium-cooled fast reactor) for achieving sustainable nuclear energy systems. In this context, an SFR is currently developed at the design concepts study stage in the Republic of Korea [Kim & Hahn 200909]. The sustainability of systems means economic, environment-friendly, proliferation-resistant, and safer systems. More specifically, this sustainability can be accomplished in terms of resource recycling and radioactive waste reduction. In the present work, the objective of fuel cycle cost modeling is to identify the impact of various conceptual options as a cost reduction measure for the Gen-IV SFR at the design concepts study stage. It facilitates the selection of several reasonable fuel cycle pathways for the future Gen-IV SFR from an economic viewpoint.

• Journal of Computing Science and Engineering
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• v.5 no.4
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• pp.346-353
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• 2011

With the advent of ubiquitous computing, a massive amount of trajectory data has been published and shared in many websites. This type of computing also provides motivation for online mining of trajectory data, to fit user-specific preferences or context (e.g., time of the day). While many trajectory clustering algorithms have been proposed, they have typically focused on offline mining and do not consider the restrictions of the underlying road network and selection conditions representing user contexts. In clear contrast, we study an efficient clustering algorithm for Boolean + Clustering queries using a pre-materialized and summarized data structure. Our experimental results demonstrate the efficiency and effectiveness of our proposed method using real-life trajectory data.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.432-432
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• 2002

Drug used in hospital is allowed marketing through after pharmacological and toxicological tests using various animals and clinical test of human in developing state. But as pre-marketing clinical study take short period with relatively a few of patients and strict selection criteria of people, pediatric, geriatric. pregnancy, liver and kidney patients may be excluded. As the safety of drug isn't completely evaluated before launching. it is important to collect and evaluate drug adverse reaction newly reported by medical practitioners and pharmacists. (omitted)

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.425-427
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• 2004

Motivation of this study is based on these two aspects: geologic uses of ASTER and application scheme of Spectral Mixture Analysis. This study aims at geologic mapping for mineral exploration using ASTER and LANDSAT 7 ETM+ at Mongolian plateau region by SMA. After basic pre-processing such as the normalization, geometric corrections and calibration of reflectance, related to endmembers selection and spectral signature deviation, both methods using spectral library and using PPI(Pixel Purity Index) are performed and compared on a given task. Based on these schemes, SMA is performed using LANDSAT 7 ETM+ and ASTER image. As the results, fraction map showing geologic rock types are enough to meet purposes such as geologic mapping and mineral potential mapping in the case of both uses of these different types of remotely sensed images. It concluded that this approach based on SMA with LANDSAT and ASTER is regarded as one of effective schemes for geologic remote sensing.

• Journal of the Korean Data and Information Science Society
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• v.18 no.2
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• pp.481-488
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• 2007

The k-means algorithm is well known for its efficiency in clustering large data sets. However, working only on numeric values prohibits it from being used to cluster real world data containing categorical values. The k-modes algorithm is to extend the k-means paradigm to categorical domains. The algorithm requires a pre-setting or random selection of initial points (modes) of the clusters. This paper improved the problem of k-modes algorithm, using the Max-Min method that is a kind of methods to decide initial values in k-means algorithm. we introduce new similarity measures to deal with using the categorical data for clustering. We show that the mushroom data sets and soybean data sets tested with the proposed algorithm has shown a good performance for the two aspects(accuracy, run time).