• Journal of Environmental Science International
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• v.24 no.1
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• pp.9-15
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• 2015

Sustainable and eco-friendly polymers, natural polymers, bio-based polymers, and degradable polyesters, are of growing interest because of environmental concerns associated with waste plastics and emissions of carbon dioxide from preparation of petroleum-based polymers. Degradable polymers, poly(butylene adipate-co-terephthalate) (PBAT), poly(propylene carbonate) (PPC), and poly(L-lactic acid) (PLLA), are related to reduction of carbon dioxide in processing. To improve a weak mechanical property of a degradable polymer, a blending method is widely used. This study was forced on the component separation of degradable polymer blends for effective recycling. The melt-mixed blend films in a specific solvent were separated by two layers. Each layer was analysed by FT-IR, DSC, and contact angle measurements. The results showed that each component in the PPC/PLLA and PPC/PBAT blends was successfully separated by a solvent.

• Proceedings of the KAIS Fall Conference
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• 2002.05a
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• pp.115-117
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• 2002

In this paper, the degree-n bifurcation set as well as the Julia sets is defined by extending the concept of the Mandelbrot set to the complex polynomial $z^{n}{\;}+{\;}c(c{\;}\in{\;}C,{\;}n{\;}\geq{\;}2)$. Some properties of the degree-n bifurcation set and the Julia sets have been theoretically investigated including the symmetry, periodicity, boundedness, connectedness and the bifurcation points as well as the governing equation for the component centers. An efficient algorithm constructing both the degree-n bifurcation set and the Julia sets is proposed using theoretical results. The mouse-operated software calico "MANJUL" has been developed for the effective construction of the degree-n bifurcation set and the Julia sets in graphic environments with C++ programming language under the windows operating system. Simple mouse operations can construct and magnify the degree-n bifurcation set as well as the Julia sets. They not only compute the component period, bifurcation points and component centers but also save the images of the degree-n bifurcation set and the Julia sets to visually confirm various properties and the geometrical structure of the sets. A demonstration has verified the useful versatility of MANJUL.

• Journal of the Korean Operations Research and Management Science Society
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• v.39 no.3
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• pp.93-115
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• 2014

In collaborative product development with multiple suppliers, buyers must manage the suppliers' activities. This empirical research investigates the performance impacts of three strategies that buyers use to manage suppliers who design interdependent components. These strategies are: Instructionism (giving clear instructions to suppliers), Teaming (forming an interactive development team with suppliers), and Delegation (transferring component development responsibilities to suppliers). Data were collected through a cross-industry web-based survey of buying firms in manufacturing industries whose products require multiple, interdependent components. A path analysis utilizing 318 survey responses indicates that Instructionism has a positive effect on design quality, and Teaming has a positive effect on design quality and component innovation. The use of Delegation is not related to any of the performance indicators. The practical implication of this research for product development managers is that both Instructionism and Teaming can be effective strategies. For the purpose of assuring design quality, a buyer should give clear instructions in detailed specifications or work closely with suppliers in development teams. If competitive priority is product innovativeness, however, the buyer should work closely with its suppliers during component development processes using a Teaming strategy.

• Journal of the Korean Institute of Navigation
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• v.25 no.4
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• pp.477-486
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• 2001

Although the ports are actually competing with various strategies, the definition and structural understanding of port competitive power are not known very much. Therefore this study has launched from this fact, and has the objective of obtaining the structural model of the competitive power, and understanding the components of the port competitive power. The following are the results of the study. First, the process began by abstracting the components that composed the port competitive power through recent research, and grouping it by the most core components using the KJ method. Also, by using the FSM(Fuzzy Structural Modeling) method to understand the structure of the grouped components, and the structural model of the port competitive power was able to obtain as the result. Second, when analyzing the obtained structural model, port expenses, main trunk location, port congestion and port facility came out to be the most important component groups, and especially port expenses was the most effective component that effected all the other components overall. Third, the component groups that were relatively less important, effected by most of the other components, and located on the top level of the structure model were the hinterland accessibility, port ownership, customs duties speed, and large ship port entrance possibility etc. Fourth, the results of this study will be able to be used when establishing competing strategies for our country's ports by proposing the relatively important components with the port competitive rower considered.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.1697-1702
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• 2003

In this paper, the effect of oxygen component in fuel on the exhaust emissions has been investigated for a direct injection diesel engine. It was tested to estimate change of engine performance and exhaust emission characteristics for the commercial diesel fuel and oxygenated blended fuel which has seven kinds of mixed ratio. And, the effects of exhaust gas recirculation(EGR) on the characteristics of NOx emission have been investigated. Ethylene glycol mono-n-butyl ether(EGBE) contains oxygen component 27% in itself, and it is a kind of effective oxygenated fuel of mono-ether group that the smoke emission of EGBE blended fuel is reduced remarkably compared with commercial diesel fuel, that is, it can supply oxygen component sufficiently at higher loads and speeds in a diesel engine. It was found that simultaneous reduction of smoke and NOx was achieved with oxygenated fuel and cooled EGR method.

• Journal of Korea Water Resources Association
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• v.48 no.11
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• pp.945-955
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• 2015

The technology of the SWG (Smart Water Grid) as one of most important national projects results in significant assignment that is closely associated with systematic management and effective operation. The individual component technics are required to establish directory and classification for the purpose of effectively managing their information related to research and development (R&D). The national science technology (S&T) standard classification tree which results in the representative example has been established with an intention to manage R&D information, human resource, and budget. It has been also revised every five years and then used in the various fields related to the evaluation, administration, and prediction of the national R&D projects. In addition, the standard classification system for R&D projects has been widely used in the UNESCO (United Nations Educational, Scientific and Cultural Organization) and EU (European Union) since the Frascati Manual was established in the Organization for Economic Cooperation and Development (OECD). Therefore, it is necessary for SWG techniques to develop the standard S&T classification tree for research management and evaluation. For this, it is essential to draw the core techniques for the SWG, which are incorporated with IT (Information Technology), NT (Nano Technology), and BT (Biology Technology).

• Journal of Biomedical Engineering Research
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• v.29 no.5
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• pp.355-363
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• 2008

In order to extract only the alpha activity related signals from EEG recordings, we have applied Constrained Independent Component Analysis (cICA), a new extension of ICA in which some a priori knowledge of the alpha activity is utilized to extract only desired components. Its extraction (or filtering) performance has been compared to that of the conventional band-pass filtering via the scalp alpha power maps and cortical source maps of the alpha activity. Our results demonstrate that the alpha power maps and cortical source maps from the cICA-extracted alpha signals reveal more focalized alpha generating regions of the brain than those from the band-pass filtered alpha EEG signals. Furthermore they match more closely the activated regions of the brain mapped using fMRI, validating our results. We believe that the cICA-based filtering approach of EEG signals is a more effective means of extracting a specific brain activity reflected in EEG signals that will result in more accurate source localization or imaging maps.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.16 no.4 s.109
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• pp.420-427
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• 2006

In this study, wind loads transmitted to a transmission tower from transmission lines are mitigated using rotational viscoelastic dampers. First, the wind load characteristics in a transmission tower is investigated considering the effect of the transmission lines through stochastic analysis. The assemblage of the transmission line and insulator are modeled as a double pendulum system connected to the SDOF model of the tower. From the result of the stochastic analysis, the background component of the overturing moment caused by the wind loads acting on the transmission lines are found to have considerable portion in the total overturning moment. Based on this observation result, a strategy Installing rotational viscoelastic damper (VED) between tower arm and transmission line is proposed for the mitigation of the transmission line reactions, which play a role as dynamic loads on a transmission tower. For the purpose of verification, time history analysis is conducted for different wind velocities and VED parameters. The analysis result shows that the rotational VED is effective for the mitigation of the background component rather than the resonance component of the transmission line reactions and achieves the reduction ratio of 50% even for higher wind speed.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.10
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• pp.5161-5178
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• 2019

Correlation Filter was recently demonstrated to have good characteristics in the field of video object tracking. The advantages of Correlation Filter based trackers are reflected in the high accuracy and robustness it provides while maintaining a high speed. However, there are still some necessary improvements that should be made. First, most trackers cannot handle multi-scale problems. To solve this problem, our algorithm combines position estimation with scale estimation. The difference from the traditional method in regard to the scale estimation is that, the proposed method can track the scale of the object more quickly and effective. Additionally, in the feature extraction module, the feature representation of traditional algorithms is relatively simple, and furthermore, the tracking performance is easily affected in complex scenarios. In this paper, we design a novel and powerful feature that can significantly improve the tracking performance. Finally, traditional trackers often suffer from model drift, which is caused by occlusion and other complex scenarios. We introduce a relocation component to detect object at other locations such as the secondary peak of the response map. It partly alleviates the model drift problem.

• Magazine of the Korean Society of Agricultural Engineers
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• v.37 no.6
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• pp.103-111
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• 1995

Drought index calculation based on the principal hydrological parameters, such as rainfall and reservoir storage, can estimate the duration and intensity of drought in irrigation reservoirs. It is difficult to build up a drought criteria since the conditions change variously by the reliability of rainfall. Because of the increasing water demands, it is urgent to prepare a generalized positive countermeasure to overcome drought. Water demands can at calculated but the estimation of drought characteristics, and the effective water management method can be established. The purpose of this study is to obtain a drought index and build up a data-base on the reservoir basins for establishing the fundamental hydrological data-base. This Index can observe the behavior of the WSI(Water Supply Index) and the component indices. The results summarized through this study are as follows. 1. WSI value of zero does not correspond to 100% in average due to the skewness in the probability distributions. 2. WSI is not a linear index; that is, given change in terms of water volume or percentage of average does not result in a proportional change on the WSI scale. 3. WSI is not always between the reservoir and the rainfall index in magnitude. This is only true if the component indices are of opposite sign. If they are of the same sign, the SWSI will often have a mangitude greater than either of the component indices. This is easily understood, because the concurrence of extreme values of the same sign for the two components is rarer than the occurrence of extreme values for either of the two components individually.