• Journal of the Institute of Electronics Engineers of Korea SD
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• v.39 no.11
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• pp.14-23
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• 2002

Two implementation methods for SOVA (Soft Output Viterbi Algorithm)of Turbo decoder are applied and verfied. The first method is the combination of a trace back (TB) logic for the survivor state and a double trace back logic for the weight value in two-step SOVA. This architecure of two-setp SOVA decoder allows important savings in area and high-speed processing compared with that of one-step SOVA decoding using register exchange (RE) or trace-back (TB) method. Second method is adjusting the reliability value with a scaling factor between 0.25 and 0.33 in order to compensate for the distortion for a rate 1/3 and 8-state SOVA decoder with a 256-bit frame size. The proposed schemes contributed to higher SNR performance by 2dB at the BER 10E-4 than that of SOVA decoder without a scaling factor. In order to verify the suggested schemes, the SOVA decoder is testd using Xillinx XCV 1000E FPGA, which runs at 33.6MHz of the maximum speed with 845 latencies and it features 175K gates in the case of 256-bit frame size.

• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.2
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• pp.72-82
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• 2005

The objective of this paper is to describe the optimization of design parameters in a large-sized commercial bus heater system by using CFD(computational fluid dynamics) analysis and Taguchi method. In order to obtain the best combination of each control factor which results in a desired performance of heater system, the parameter design of the Taguchi method is adopted for the robust design considering the dynamic characteristic. The research activity may be divided into four phases. The first one is analyzing the problem, i.e., ascertaining the influential factors. In the second phase the levels were set in such a way that their variation would significantly influence the response. In the third phase the experimental runs were designed. In the final phase the planned runs were carried out numerically to evaluate the optimal combination of factors which is able to provide the best response. In this study, eight factors were considered for the analysis: one with two level and seven with three level combinations comprising the $L_{18}(2^1{\times}3^7)$ orthogonal array. The results of this study can be summarized as follows ; (i)The optimum condition of control factor is a set of <$A_2\;B_1\;C_3\;D_3\;E_1\;F_2\;G_3\;H_2$> where A is shape of the outer fin, B is pitch of the outer fin, C is height of the outer fin, D is the inner fin number, E is the inner fin height, F is length of the flame guide, G is diameter of the heating element and H is clearance between air guide and heating element. (ii)The heat capacity of heated discharge air under the optimum condition satisfies the equation y=0.6M w here M is a signal factor. (iii)The warm-up rate improves about three times, more largely as com pared with the current condition, which results in about 9.2minutes reduction.

• Journal of Computing Science and Engineering
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• v.4 no.1
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• pp.53-79
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• 2010

This study proposes a framework to investigate the factors of mobile web success in the context of e-commerce, and the relative importance of these success factors in selecting the most preferred mobile web. First, the Updated Delone and Mclean IS success model (2003) is chosen to extract significant mobile web success factors in the context of e-commerce. Second, it is extended through applying an Analytic Network Process (ANP) approach for investigating the relative importance of each factor and ranking alternative mobile webs in the context of e-commerce. The choice of success measure is a function of the context, which is the objective of this study. Thus, the present study is aimed at evaluating the success of an e-commerce mobile web by customizing measures of the Updated Delone and McLean IS Success model according to the context.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.5
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• pp.359-364
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• 2013

This study was conducted to develop a model to estimate crop leaf surface temperature. The results were as following; A definition for the daily time based on elapsed time from the midnight (00:00) as "E&E time" with the unit of Kmin. was suggested. The model to estimate the scaled temperature ($T^*e$) of crop leaf surface temperature by scale factor ($T^*$) according to the "E&E time : Kmin."(X) was developed as eq. (1) $T^*e=0.5{\cdot}sin(X+780)+0.5$ (2) $T^*=(Tx-Tn)/(Tm-Tn)$, Tx : Daily leaf temperature, Tm : Daily maximum leaf temperature, Tn : Daily minimum leaf temperature. Relative sensitivity of the measured temperature compared to the estimated temperature of red pepper, soybean and persimmon was 1.078, 1.033 and 0.973, respectively.

• The Journal of the Acoustical Society of Korea
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• v.22 no.1E
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• pp.19-25
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• 2003

Ryu et al. recently proposed a multiple target angle-tracking algorithm without a data association problem. This algorithm, however, shows the degraded performance on evasive maneuvering targets, because the estimated signal subspace is d,:graded in the algorithm. In this Paper, we proposed a new algorithm, in which VFF-PASTd (Variable Forgetting Factor PASTd) algorithm is applied to Ryu's algorithm to effectively handle the evasive target tracking with better time-varying signal subspace.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2004.11a
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• pp.157-157
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• 2004

• Journal of the Korean Geotechnical Society
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• v.30 no.3
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• pp.59-72
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• 2014

For circular rigid footings with a rough base on sand, combined vertical - moment loading capacity was studied by three-dimensional numerical modelling. Mohr-Coulomb plasticity model with the associated flow-rule was used for the soil. After comparing the results of the swipe loading method, which can construct the interaction diagram with smaller number of analyses, and those of the probe loading method, which can simulate the load-paths in the conventional load tests, it was found that both loading methods give similar results. Conventional methods based on the effective width or area concept and the results by eccentricity factor ($e_{\gamma}$) were reviewed. The results by numerical modelling of this study were compared with those of previous studies. The combined loading capacity for vertical (V) - moment (M) loading was barely affected by the internal friction angle. It was found that the effective width concept expressed in the form of eccentricity factor can be applied to circular footings. The numerical results of this study were smaller than the previous experimental results and the differences between them increased with the eccentricity and moment load. Discussions are made on the reason of the disparities between the numerical and experimental results, and the areas for further researches are mentioned.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.6
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• pp.2551-2557
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• 2012

This study analyses the relative importance of R&D business model of the small and medium manufacturing firm. We also compare samples by classifying by its properties, technology and market circumstance. The most important factor of the R&D business model is marketing factor and infrastructure factor is relatively less important. Also the relative importance of the R&D business model is different according to firm's properties and technology. So when government establishes the R&D policy, he focuses on designing the R&D business model.

• The Journal of Society for e-Business Studies
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• v.18 no.4
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• pp.241-255
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• 2013

Convergence service, which is a combination of various services, is becoming more important. Among the many examples of convergence service, this study aims to analyze telematics service. By dividing Telematics service into information services and entertainment services, it was empirically proved that the relationship between each dimensions of TAM (perceived ease of use, perceived usefulness, purchase intention) and each service satisfaction, price, design factor. According to the result of structure equation model, service satisfaction and design factor have a significant effect on perceived ease of use, but not on perceived usefulness. It means that the perceived ease of use factor should be emphasized, because of service characteristics that are used during driving.

• Journal of Life Science
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• v.26 no.3
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• pp.338-345
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• 2016

This study investigated the antioxidant and anti-inflammatory activity of ethanol extract from the flowers of Weigela subsessilis (WS-E) in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. The total polyphenol and flavonoid content was 719.19±0.04 μg tannic acid equivalents/ml and 644.87±0.02 μg quercetin equivalents/ml, respectively. The antioxidant activities of WS-E were measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and superoxide anion radical scavenging activity. The antioxidant activities of WS-E increased markedly, in a dose-dependent manner. To screen for anti-inflammatory agents, the inhibitory effects of WS-E on the production of proinflammatory cytokines in the LPS-stimulated RAW 264.7 macrophages was examined. WS-E had no effect on cell viability at a concentration of 100 μg/ml. Nitric oxide (NO) and interleukin (IL)-6 production were inhibited in a dose-dependent manner (p<0.05). WS-E had no effect on the production of tumor necrosis factor (TNF)-α at a concentration of 0.16–20 μg/ml but induced TNF-α at a concentration of 100 μg/ml. Inducible nitric oxide synthase (iNOS) expression was also inhibited at lower concentrations (p<0.05). In addition, WS-E reduced the activation of nuclear factor (NF)-κB by inhibition of inhibitoy (I) κB phosphorylation in RAW 264.7 macrophages upon stimulation with LPS (100 ng/ml) for 24 h but not that of mitogen-activated protein kinase (MAPK). These results suggest that WS-E may be a useful antioxidant and anti-inflammatory agent in functional cosmetics.