• Journal of the Korean Society of Combustion
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• v.6 no.2
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• pp.1-7
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• 2001

In order to elucidate the turbulent burning velocity of the two-component fuel mixtures, the lean and rich two-component fuel mixtures, where methane, propane and hydrogen were used as fuels, were prepared keeping the laminar burning velocity nearly the same value. Clear difference in the measured turbulent burning velocity at the same turbulence intensity can be seen among the two-component fuel mixtures with different addition rate of fuel, even under nearly the same laminar burning velocity. The burning velocities of lean mixtures change almost monotonously as changing addition rate, those of rich mixtures, however, do not show such a monotony. These phenomena can be explained qualitatively from the local burning velocities, estimated by considering the preferential diffusion effect for each fuel component. In addition, a prediction expression of turbulent burning velocity proposed for the one-component fuel mixtures can be applied to the two-component fuel mixtures by using the estimated local burning velocity of each fuel mixture.

• Journal of Internet Computing and Services
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• v.6 no.2
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• pp.49-57
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• 2005

Connector's role between components is very important in the CBD(Component Based Development). The most connector has process ADL based rrethod was choosing FIFO method by component request. But in case many component's with various characteristics request It is difficult that this method operate efficiently, In this research, I did design and implement priority connector considering component's processing time, Also, I used Wright architecture for formal specification. Application result of proposed connector was spend more 388ms compares with existent FIFO method in total processing time. But this method could handle preferentially from components that have short processing time. Also, in case of component's waiting time in connector, existent FIFO method is 23323,1 ms and proposal method is 12731.27ms, So, proposal method could reduce waiting time for component process.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.7
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• pp.621-628
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• 2016

This paper presents the development of a deadweight type 6-component force/moment generator for estimating characteristics of multi-component loadcell. Several new methods in moment generation are introduced in order to produce accurate force / moment and to minimize coupling effect between each force or moment components. In order to verify the reliability of the calibration system developed, estimation of the method for generating moment components and cross measurements between force or moment components are carried out utilizing a commercial torque cell and both-ends fixed beam designed in this paper.

• Journal of the Korean Chemical Society
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• v.36 no.1
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• pp.113-124
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• 1992

The pattern recognition methods of chemometrics have been applied to multivariate data, for which ninety four Korean ancient glass pieces have been determined for 12 elements by neutron activation analysis. For the purpose, principal component analysis and non-linear mapping have been used as the unsupervised learning methods. As the result, the glass samples have been classified into 6 classes. The SIMCA (statistical isolinear multiple component analysis), adopted as a supervised learning method, has been applied to the 6 training set and the test set. The results of the 6 training set were in accord with the results by principal component analysis and non-linear mapping. For test set, 17 of 33 samples were each allocated to one of the 6 training set.

• The KIPS Transactions:PartD
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• v.8D no.6
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• pp.761-770
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• 2001

As software industry is rapidly evolving, IT business enterprises have been meeting with cutthroat competition in developing software. As software reusability, time to market, and maintainability are considered as a competitive edge, software component techniques have lately attracted considerable attention. Currently, although there are some supporting tools for developing software components, they do not have tight connections among component developing processes such as component identification, component modeling, detailed design, code generation, deployment, and testing. And it is restrictive for users to construct various scales of components on component platform architecture. In this paper, we provide an implementation and a design of a supporting tool for constructing platform-independent software components, which covers all development lifecycles of components. In the phase of component modeling, platform independent, conceptual components are identified from domain model information in the view of system partitioning. Detailed design and implementation of a component are performed on the J2EE platform architecture. And the changes on the design model and source codes are consistently managed by using round-trip techniques.

• Journal of Broadcast Engineering
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• v.15 no.6
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• pp.749-756
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• 2010

The signal space diversity is one of the promising transmission techniques in next generation mobile TV service. However, DVB-T2 does not consider the multiple antennas (MIMO) so that the cyclic Q-delay method, a component interleaver in DVB-T2, causes a critical issue in detecting symbols at the receiver side by increasing the inter-symbol dependency. To solve this problem, the component-swapping technique is proposed, which limits the inter-symbol dependency in order to reduce detection complexity. In this paper, the achievable gain of a component-swapping technique combined with 16K LDPC code defined in DVB-T2 is evaluated by computer simulations. From the results, the gain is confirmed in terms of BER and receive complexity compared to legacy component interleaver methods.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2000.11a
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• pp.89-92
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• 2000

Non-aqueous tape casting of LTCC with PVB binder has been studied in a continuous tape casting machine. The aim of the study was to evaluate this type of system in the different Binder/Plasticizer and solid content compositions. Each four slurry compositions were used in the experiments with varied binder/plasticizer and solid content. All the slurries gave good quality tapes with smooth surfaces without blisters or pinholes. The highest mechanical properties was obtained for the B/P=3.0, powder content 70vol% composition from 52 ${\mu}{\textrm}{m}$ green tapes, a tensile strength of 4.6 MPa and a linear extension of 29.5%

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.30 no.1
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• pp.17-22
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• 2017

Effects of pH value and deposition time on the electrical properties of (NMC) Ni-Mn-Cu-O and (NMCC) Ni-Mn-Cu-Co-O thin films were investigated. The NMC and NMCC films were prepared by spin spray method. The crystal structure and thickness of the annealed films were changed by the pH value and deposition time, respectively. A single phase of cubic spinel structure was confirmed for the annealed films deposited from solutions with pH 7.6. The resistivity of the annealed films was affected by the crystal structure and microstructure. The TCR (temperature coefficient of resistance) was dependent on the $Mn^{3+}/Mn^{4+}$. Typically, the resistivity of $70.5{\Omega}{\cdot}cm$ and TCR of -3.56%/K at room temperature were obtained for NMCC films deposited from solutions with pH 7.6 for 5 min, and annealed at $450^{\circ}C$ for 3 h.

• The Korean Journal of Applied Statistics
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• v.26 no.6
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• pp.933-942
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• 2013

Common factor analysis and principal component analysis represent two technically distinctive approaches to exploratory factor analysis. Much of the psychometric literature recommends the use of common factor analysis instead of principal component analysis. Nonetheless, factor analysts use principal component analysis more frequently because they believe that principal component analysis could yield (relatively) less accurate estimates of factor loadings compared to common factor analysis but most often produce similar pattern of factor loadings, leading to essentially the same factor interpretations. A simulation study is conducted to evaluate the relative performance of these two approaches in terms of factor pattern recovery under different experimental conditions of sample size, overdetermination, and communality.The results show that principal component analysis performs better in factor recovery with small sample sizes (below 200). It was further shown that this tendency is more prominent when there are a small number of variables per factor. The present results are of practical use for factor analysts in the field of marketing and the social sciences.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.5
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• pp.778-785
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• 2017

This paper presents a control method for reducing the distortion of the grid current at a grid-connected three-level neutral point clamped (NPC) inverter. The grid current is distorted from the 5th and 7th harmonic components in the stationary frame current also the 6th harmonic component in the synchronous frame current. In this paper, the 6th harmonic component on synchronous frame is controlled by using all-pass filters (APFs) and proportional integral (PI) controllers for distortion of the grid side. When transformed the 6th harmonic component is controlled, the 5th and 7th harmonic components are reduced. The validity of the proposed control method is verified by simulation and experiment results using a 25kW three-level NPC inverter.