• Journal of Korea Multimedia Society
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• v.9 no.3
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• pp.315-322
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• 2006

In the application rising IP multicast, the waste of available bandwidth occurs of reducing of transmission rate in non-congestion local caused by reducing of transmission rate in congestion local. In this paper, to solve such a problem, we propose a dynamic multicast method using IP multicast and overlay multicast. In proposed method, we elected a local representative for overlay multicasting. When the transmission rate of a group is less than transmission rate threshold, the representative can transmits duplicative packets. In simulation results, it was known that proposed method uses bandwidth more efficiently.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.32 no.10
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• pp.805-816
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• 2008

The present work reviews the methods to evaluate elastic-plastic material characteristics by indentation tests. Especially the representative stress and strain values used in some papers are critically analyzed. The values should not only represent the load-depth curve, but also represent the whole of deformed material around the impression. We briefly introduce other indentation techniques to evaluate residual stresses, creep properties, and fracture toughness. We also review some technical problems that are related to the accuracy issues in indentation tests.

• Bulletin of the Korean Chemical Society
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• v.30 no.7
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• pp.1588-1592
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• 2009

Lithium cyanoaluminum hydride (LCAH) was prepared by the metal cation exchange reaction of sodium cyanoaluminum hydride with lithium chloride in tetrahydrofuran. The reducing characteristics of LCAH were explored systematically by the reaction with selected organic compounds containing representative functional groups under the standardized conditions (tetrahydrofuran, 0 ${^{\circ}C}$). The reducing ability of LCAH was also compared with of the sodium derivative, sodium cyanoaluminum hydride (SCAH). Generally, the reducing behavior of LCAH resembles that of SCAH closely, but the reactivity of LCAH toward representative organic functional groups appeared to be stronger than that of SCAH. Thus, the regent reduces carbonyl compounds, epoxides, amides, nitriles, disulfides, carboxylic acids and their acyl derivatives to the corresponding alcohols or amines, at a relatively faster rate than that of SCAH. The cyano substitution, a strong election-withdrawing group, diminishes the reducing power of the parent metal aluminum hydrides and hence effects the alteration of their reducing characteristics.

• Journal of the Korea Society of Computer and Information
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• v.23 no.2
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• pp.35-43
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• 2018

In this paper, we propose a grid-based efficient routing protocol for a mobile sink in wireless sensor networks. In the proposed protocol, the network is partitioned into grids and each grid has a grid head. For the efficient routing to a mobile sink, the proposed protocol uses a mobile sink representative node to send the data to a mobile sink and grid heads are used as a mobile sink representative node. Furthermore, the proposed protocol uses nodes in the boundary of the center grid as position storage nodes. The position storage nodes store the position of a mobile sink representative node and provide source nodes with it for data delivery. With these features, the proposed protocol can reduce a lot of overhead to update the position information and improve the delay of data delivery to a mobile sink. The proposed protocol performs better than other protocols in terms of the delay and the energy consumption per node in the performance evaluation.

• Journal of the Korea Safety Management & Science
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• v.14 no.1
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• pp.75-85
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• 2012

In this study, the representative hand shapes for the adult Koreans were analyzed by factor analysis and cluster analyses. The analyses were conducted on the anthropometric data of 58 hand dimensions from 325 subjects having nonhomogeneous demographics. Maximum hand circumference, first phalanx length of index finger, and ratio between the two measures were the independent variables for the cluster analyses. The results of the study showed that Korean hand shapes can be divided into 2 clusters irrespective of their size for each of the male and female group. There were slight differences in component ratio of hand shapes with respect to the occupation and the age, but their differences were not statistically significant. The representative Korean hand shapes and their anthrpometric dimensions could be used to design and establish proper sizing system for various hand operating devices.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.346-349
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• 2010

In this study several unit hydrographs by rainfall storms are derived and moving averaged unit hydrograph is extracted from them based on the rainfall-runoff data in a small basin 8.5 $km^2$ wide. And peak discharges and peak times of the unit hydrographs are investigated and reviewed. And then a representative unit hydrograph of the moving averaged one is applied to the linear convolution integration for obtaining the flood discharge hydrograph and peak discharge and time of its result are researched and inspected. Variance in application of the representative unit hydrograph in a basin on assumption of linearity is appeared and this is given as a counterevidence about that the runoff response from rainfall on a basin has nonlinear characteristics. And As a result of application of derived representative unit hydrograph the errors in peak discharge and time are investigated.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1999.11a
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• pp.420-423
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• 1999

In this paper, we propose the method which efficiently obtain information through edit and retrieval of video data easily and rapidly. To support this method, extract the candidate representative frame using existing scene change detection method and the user selects representative frame for video segmentation at his desire, and then visualization indexing methods supported by logical-links enable users to freely merge and split each scene.

• Coupled systems mechanics
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• v.6 no.1
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• pp.1-15
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• 2017

Despite the exceptional mechanical properties of individual carbon nanotubes (CNTs), the effective properties of CNT-reinforced composites remain below expectations. The composite's microstructure has been identified as a key factor in explaining this discrepancy. In this contribution, a method for generating representative volume elements of aligned CNT sheets is presented. The model captures material characteristics such as random waviness and entanglement of individual nanotubes. Thus it allows studying microstructural effects on the composite's effective properties. Simulations investigating the strengthening effect of the application of a pre-stretch on the CNTs are carried out and found to be in very good agreement with experimental values. They highlight the importance of the nanotube's waviness and entanglement for the mechanical behavior of the composite. The presented representative volume elements are the first to accurately capture the waviness and entanglement of CNT sheets for realistically high volume fractions.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.6_3
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• pp.1191-1197
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• 2022

Recently, many studies have been conducted to utilize the digital aerial photogrammetry method in the field of cadastral surveying. The representative models of digital cameras currently used for aerial photogrammetry are classified into line-type and convex-type cameras, so the representative models were selected and analyzed. The purpose of this study was to analyze whether the accuracy suggested by the cadastral survey enforcement rules was satisfied by comparing the orthogonal and ortho image performance. As a result, there were some representative false points that exceeded the acceptable range, but the results extracted from most of the images were shown to satisfy the acceptable range. Therefore, it can be said that the application of digital aerial photogrammetry to the cadastral field in the technical aspect has sufficient potential.

• Journal of Korean Home Economics Education Association
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• v.27 no.2
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• pp.137-147
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• 2015

The target pattern is introduced for practicing a balanced dietary menu planning, but Korean soup and stew, cooked with several kinds of materials, have a problem with food group assignment in the target pattern. This study thus set out to calculate the representative nutritional values of Korean soup and stew based on intake(by 2010 Korean National Health and Nutrition Examination Survey, age group of 13~19) and preference(by select the 3 kinds of favorite soup and stew each). Total of 235 middle school students were participated by way of questionnaire, and data were analyzed. Representative energy value of vegetable soup and stew by intake were $65kca{\ell}$ and $116kca{\ell}$, respectively, which were very much different with the vegetable group representative energy value of $14kca{\ell}$ in target pattern. Representative energy value of meat fish egg legume soup and stew by intake were $149kca{\ell}$ and $211kca{\ell}$, respectively, which were very much different with the representative meat fish egg legume energy value of $94kca{\ell}$ in target pattern. As result, it is not proper to assign vegetable soup stew to vegetable food group and meat fish egg legume soup stew to meat fish egg legume food group. Representative energy values of soup and stew by preference were not much different except meat fish egg legume soup($149kca{\ell}$ by intake, $218kca{\ell}$ by preference). As conclusions, it maybe desirable to categorize soup and stew as independent food group. For more accurate energy adjustment in menu planning, devide soup and stew, and further divide to vegetable and meat fish egg legume groups may necessary.