• The Journal of the Korea Contents Association
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• v.8 no.2
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• pp.74-82
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• 2008

This paper investigates chrominance reconstruction methods that reconstruct subsampled chrominance information efficiently using the correlation between luminance and chrominance components in the decompression process of compressed images, and analyzes drawbacks involved in the adaptive-weighted 2-dimensional linear interpolation among the methods, which shows higher efficiency in the view of computational complexity than other methods. To improve the drawback that the spatial frequency distribution is not considered for the decompressed image and to support the application on a low-performance system in behalf of 2-dimensional linear interpolation, this paper proposes the multi-mode reconstruction method which uses three reconstruction methods having different computational complexity from each other according to the degree of edge response of luminance component. The performance evaluation on a development platform for embedded systems showed that the proposed reconstruction method supports the similar level of image quality for decompressed images while reducing the overall computation time for chrominance reconstruction in comparison with the 2-dimensional linear interpolation.

• Hwankyungkyoyuk
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• v.20 no.2
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• pp.78-92
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• 2007

The purindicator and its application through the application of the eco-city concept. To achieve this aim, this study execute to erect eco-city concept, to develop urban evaluation indicator for the fifth and sixth graders of elementary school, to survey for elementary school teacher in Daegu and to develop application of urban evaluation indicator for the fifth and sixth graders of elementary school. The result of study can be summarized as follow. First, erecting the eco-city concept and urban evaluation indicator for the fifth and sixth graders of elementary school was developed with 14 objects, such like that saving and sound circulation of water resource, sound atmosphere. Second, The result of survey, generally, teachers evaluated that Daegu has problems. The degree of interest of urban environmental problem of Daegu showed that each problem had relatively equal distribution. Teachers had positive response that the ecocity concept applied to environmental education of elementary school. Selection of educational contents had distinct tendency with application of the concept of ecocity. Teachers indicated several problems in environmental education of elementary school. Third, We develop application of indicator for the fifth and sixth graders of elementary school. We concluded that developing application of indicator will offer as follows: First, student and teacher can logically understand urban environmental problems. Second, application of indicator had role of useful tool for environmental education of elementary school.

• International Journal of Highway Engineering
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• v.2 no.2
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• pp.139-148
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• 2000

Currently existing Accelerated Pavement Testing (APT) systems developed in several countries have been employed mainly to test the performance of asphalt pavement. Meanwhile, the length of concrete pavement is similar to that of asphalt pavement in expressways of Korea. and is expected to increase due to its durability and compatibility to our weather condition. To meet the society's demand of having our own APT system which can examine the long-term performance of concrete pavement, a contract study to develop Korea Accelerated Loading and Environment Simulator (KALES) for concrete pavement has been performed for 3 years from 1997 through 1999. Through the project, a detailed design was Peformed for the KALES system in which the entire structure of KALES, loading mechanism, wandering mechanism, suspension system, driving system were proposed. Also in advance to design a full-scale KALES system, a sample scale model was manufactured and tested for operating motion and force distribution. It is evident that the proposed prototype KALES system will provide higher degree of traffic simulation and durable operation, based on the satisfactory fatigue analysis.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.5
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• pp.615-627
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• 1997

An experiment was performed to local heat transfer coefficient and Nusselt number in the circular duct of 180.deg. bend for Re=6*10$^{4}$, 8*10$^{4}$ and 1*10$^{5}$ at swirling flow and non-swirling flow conditions. The test tube with circular section was made by stainless which has curvature ratio 9.4. The wall of test tube was heated directly by electrical power to 3.51 kw and swirling motion of air was produced by a tangential inlet to the pipe axis at the 180 degree. Measurements of local wall temperatures and bulk mean temperature of air are made at four circumferential positions in the 16 stations. The wall temperatures show particularly reduced distribution curve at bend for non-swirling flow but this effect does not appear for swirling flow. Nusselt number distributions for swirling flow which was calculated from the measured wall and bulk temperatures were higher than that of non-swirling flow. Average Nusselt number of swirling flow increased about 90 ~ 100% than that of non-swirling flow whole through the test tube. The Nu/N $u_{DB}$ values at the station of 90.deg. for non-swirling flow and swirling flow are respectively about 2.5 and 4.8 at Re=6*10$^{4}$. Also that is good agreement with Said's result for non-swirling flow. flow.

• Journal of the Korea Computer Industry Society
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• v.6 no.3
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• pp.519-528
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• 2005

Computers have been increasingly recognized as tools for teaming, in addition to supporting industrial works. Such advantages e-Learning have as teaming at any time and place, distribution and management of standardized contents, mentoring with learners, immediate feed-backs, and dynamic learning have been applied in a variety of divisions. Despite of the researches and interests, the study on the different views between teachers who design and operate e-learning and students who receive lessons hasn't been enough. So it studied the recognition of middle school teachers and students on the e-Learning. <중략>The research result showed that there were similarity in the views between teachers and students on the concept of e-Learning. Many teachers and students have experienced the e-Learning directly or indirectly. Teachers and students showed similar opinions on the beforehand education and preferred subjects of the e-Learning. But the students required fast and immediate feedback of the teachers. Teachers and students showed similar opinions on the utilization of multimedia components to achieve the goal of education. But teachers thought that immediate feedback was important. The students thought it important to control the degree of difficulty. It suggests a way to activate the e-Learning of middle school efficiently with the research result.

• Journal of the Korean Applied Science and Technology
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• v.31 no.3
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• pp.408-415
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• 2014

In order to prepare high-quality activated carbons (ACs), coal tar pitch (CTP), and mixtures of CTP and petroleum pitch (PP) were activated with KOH. The ACs prepared by activation of CTP in the range of $700{\sim}1000^{\circ}C$ for 1~5 h had very porous textures with large specific surface areas of $2470{\sim}3081m^2/g$. The optimal activation conditions of CTP were determined as CTP/KOH ratio of 1:4, activation temperature of $900^{\circ}C$, and activation time of 3 h. The obtained AC showed the highest micro-pore volume, and pretty high specific surface area and meso-pore volume. The micro-pore volumes and specific areas of activated mixtures of CTP and PP were similar to each other but the meso-pore volume could be increased. In order to change the degree of crystallinity of precursors before KOH activation process, the CTPs were carbonized in the range of $500{\sim}900^{\circ}C$. As the carbonization temperature increased, the specific surface area and pore volume of the activated ACs with the same activation conditions for CTP decreased dramatically. It was demonstrated that the increased pore size distribution of AC electrodes in the range of 1 to 2 nm plays an important role in the performance of electric double-layer capacitor.

• Journal of the Earthquake Engineering Society of Korea
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• v.7 no.4
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• pp.63-69
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• 2003

In this study seismic design procedure for buckling-restrained braced frame systems was proposed using hysteretic energy spectrum and accumulated ductility spectrum constructed from single degree of freedom systems. The hysteretic energy spectra and accumulated ductility spectra corresponding to target ductility ratio were constructed first. The cross-sectional area of braces required to meet a given target displacement was obtained by equating the hysteretic energy demand to the accumulated plastic energy dissipated by braces. Twenty earthquake records were utilized to construct the spectra and to verify the validity of the design procedure. According to analysis results of three- and eight-story buckling-restrained braced frame structures designed using the proposed method, the mean values for the top story displacement correspond well with the given performance target displacements. Also, the inter-story drifts turned out to be relatively uniform over the structure height, which is desirable because uniform inter-story drifts indicate uniform damage distribution. Therefore if was concluded that the proposed energy-based method could be a reliable alternative to conventional strength-based design procedure for structures with buckling-restrained braces.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.5
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• pp.765-769
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• 2001

Starches of flavored glutinous rice were analyzed by using scanning electron microscope (SEM) and differential scanning calorimetry (DSC) and tested on the starch granule susceptibility to 15% H$_2$SO$_4$, glucoamylase and $\alpha$-amylase. The shape of starch granules form flavored glutinous rice varieties was polygonal and the size was 4~6 $\mu$m in diameter. According to DSC, glutinous rice starch showed onset temperature (T$_{o}$) range 59.8~62.5$^{\circ}C$ and KR92021-B-B-42-3-B and KR92021-B-B-165-1-B showed higher enthalpy ($\Delta$H) on gelatinization than others. The starches from KR92021-B-B-5-2-B and KR92021-B-B-42-3-B showed lower hydrolysis rate using 15% H$_2$SO$_4$ than KR92021-B-B-165-1-B. KR92021-B-B-5-2-B showed higher degree of hydrolysis of glucoamylase and $\alpha$-amylase than the others.

• Polymer(Korea)
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• v.35 no.6
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• pp.610-614
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• 2011

In this study, the effect of solvent on the pre-irradiation grafting of VBC(vinylbenzyl chloride) onto a ETFE(polyethylene-co-tetrafluoroethylene) was evaluated. ETFE film was irradiated to generate radical species onto its backbone chain. Each irradiated film was immersed into VBC monomer mixtures diluted with various solvents such as toluene, heptane, and isopropanol etc. for grafting process and then the degree of grafting of each film was measured. FTIR analysis confirmed that the VBC-g-ETFE film was successful prepared. For the films prepared in the various solvents, the mechanical strength and the distribution pattern of the graft polymer over the cross-section of the films were measured and the effect of solvent was evaluated.

• Korean Journal of Remote Sensing
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• v.6 no.2
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• pp.89-113
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• 1990

The purpose of this study is to develop means to apply GIS and remote sensing technology to the analysis of Korean urban open spaces. To achieve this objective, a framework of analysis of urban open spaces was developed, and then the framework was applied for the evaluation of the potential and suitability of open spaces of Ansan City, which is a new town developed to accomodate industries relocation from Seoul, Korea, mainly due to their pollution problems. The software used in this study are IDRISI, a grid-based GIS, and KMIPS, a remote sensing analysis system. Both packages are based on IBM PC/AT computers with Microsoft DOS. Landsat MSS and TM data were used for the land use classification, land use change detection, and analysis of transformed vegetation indices. The size of the geographic data base is 110 rows and 150 columns with the spatial resolution of 100m$\times$100m. The framework of analysis includes both quanititative and qualitative analysis of open spaces. The quantitative analysis includes size and distribution of open spaces, urban develpment of open spaces, and the degree of vegree of vegetation removal of the study area. The qualitative analysis includes evaluative criteria for primary productivity of land, park use potential, major visual resources, and urban environmental control. The findings of this study can be summarized as follows. First, the size of builtup areas increased 18.73km$^2$, while the size of forest land decreased 10.86km$^2$ during last ten years. Agricultural lands maintained its size, but shifted toward outside of the city into forest. Second, the potential of open spaces for park use is limited mainly due to their lack of accessibility and connectivity among open spaces, in spite of ample acreage and good site conditions. Third, major landscape elements and historic sites should be connected to the open space system of the city by new accesses and buffers.