• Journal of Korea Multimedia Society
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• v.21 no.8
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• pp.821-828
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• 2018

Image Enhancement is used in various applications. Among them, unsharp masking methods can improve the contrast with a simple operation. However, it has problems of noise enhancement and halo effect caused by the use of a single filter. To solve this problems, adaptive processing using multi-scale and bilinear filters is being studied. These methods are effective for improving the halo effect, but it require a lot of calculation time. In this paper, we want to simplify adaptive filtering by generating a weight map based on local brightness. This weight map enables adaptive processing that eliminates the halo effect through a single multiplication operation. Through experiments, we confirmed the suppression of the halo effect through the result image of the proposed algorithm and existing algorithm.

• Asian Journal of Innovation and Policy
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• v.3 no.1
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• pp.72-93
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• 2014

This study analyzed the factors that influence the research productivity of 236 graduate students who are funded by the Global Ph.D. Fellowship Program of the National Research Foundation of Korea. Research productivity was measured by the number of SCI publications, and the explanatory factors are the demographic factor, the financial factor, the reputation of institutions and the supervisor factor. This study included 2 indices such as the reputation of institutions and the research productivity of supervisors to check the halo effect unlike other studies. Results are as follows: 1) no gender difference, 2) better performance by younger age group, 3) no difference even if the students are additionally funded by other research support programs, 4) no halo effect by the reputation of institution but rather better performance from low ranked universities, 5) and a positive halo effect by supervisors.

• Journal of Distribution Research
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• v.9 no.2
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• pp.101-122
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• 2004

In this study, two alternative models are developed and tested in order to investigate the relationship between retailer image and its private brand attitude. The halo effect model hypothesizes that retailer image is related as a halo in private brand evaluation and the summary construct model hypothesizes that retailer image functions as a summary construct of private brand evaluation. The results indicate there are moderating effects of 1) familiarity with a private brand and 2) the characteristics of a product category High familiarity is related with the summary construct model and low familiarity the halo effect model. In private brand food, the summary construct model fits better and explains more adequately that private brand evaluation influences retailer image as a summary construct. In private brand clothes, however, the halo effect model performs better in explaining the relationship between retailer image and private brand attitude.

• Journal of Convergence for Information Technology
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• v.9 no.8
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• pp.123-133
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• 2019

This research empirically investigated halo effect in evaluating culture and art performance program. We diagnosed halo effect by using correlation analysis, factor analysis, and regression model on results and scores of fifteen evaluation indicators within three categories for the 107 Local Representative Performance Art Festivals in 2014 and 2015. The results indicates strong possibility of halo effect in culture and art performance evaluation. The correlation coefficients between evaluation indicators is higher than 0.5 and factor structure does not match with evaluation categories in both years. Scores in categories and standard deviations also are also significantly correlated with each other. The results implies that more sophisticated standard, diversification of evaluator, education, and meta-anlysis are need to control halo effect.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.73.3-73.3
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• 2017

Environment has a significant impact on the evolution of dark halo profiles. We used a cosmological N-body simulation based on WMAP5 cosmology to study environmental effects on halo profiles. Host haloes located in sparse regions are highly concentrated, and more massive haloes have higher concentration index. This is because mass accretion affects only the outer part of the halo and consequently increase the virial radius having no effect on the scale radius. Conversely, host haloes located in dense regions have low concentration index. This is because frequent mergers affect even the inner part of the halo. So, scale radius increases with the growth of virial radius. Evolutions of subhalo profiles are essentially different from those of host haloes because subhaloes undergo tidal stripping. The stripping begins once a subhalo approaches closer than ~3 virial radii of the host halo. During the stripping, the inner part of the subhalo keep following NFW profile, but the mass of the outer part gradually decreases. As a result, when the subhalo reaches the pericenter of its host, only about inner 30% of the subhalo follows the NFW profile.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.46-46
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• 2014

Interactions such as mergers and flybys play a fundamental role in shaping galaxy morphology. We used the Horizon Run 4 cosmological N-body simulations to study the frequency and the type of halo interactions as a function of the environment, the separation p, the mass ratio q, and the target halo mass. We defined targets as haloes more massive than 10^11 Msun/h, and a target is interacting if it is located within the virial radius of a neighbour halo more massive than 0.4 times the target mass. We find that the interaction rate as a function of time has a universal shape for different halo mass and large-scale density, with an increase and saturation. Larger density yield steeper slopes and larger final interaction rates, while larger masses saturate later. Most interactions happen at large-scale density contrast ${\delta}$ about 10^3, regardless of the redshift. We also report the existence of two modes of interactions in the (p,q) plane, reflecting the nature (satellite or main halo) of the target halo. These two trends strongly evolve with redshift, target mass, and large-scale density. Interacting pairs have similar spins parameters and aligned spins, with radial trajectories, and prograde encounters for non-radial trajectories. The satellite trajectories become less and less radial as time proceed. This effect is stronger for higher-mass target, but independent of the large-scale density.

• Journal of Korea Multimedia Society
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• v.25 no.9
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• pp.1273-1283
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• 2022

This paper presents a locally adaptive HDR algorithm using the integral image and MSRCR for LDR images with inadequate exposure. There are two categories in controlling the dynamic range, which are global and local tone mappings. Since the global ones are relatively simple but have some limitations at considering regional characteristics, the local ones are often utilized and MSRCR is a representative method. MSRCR gives moderate results, but it requires lots of computations for multi-scale surround Gaussian functions and produces the Halo effect around the edges. Therefore, in order to resolve these main problems, the proposed algorithm remarkably reduces the computation of the surrounds due to the use of the integral image. And a set of variable-sized windows is adopted to decrease the Halo effect, according to the type of pixel's region. In addition, an offset controlling function is presented, which is mainly affected to the subjective image quality and based on the global input and the desired output means. As the results, the proposed algorithm no more use Gaussian functions and can reduce the computation amount and the Halo effect.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.36D no.9
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• pp.21-30
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• 1999

Halo pocket implantation in MOSFETs, which is known to be an efficient method to provent the punchthrough and threshold voltage roll-off phenomena, decreases the drain current of MOSFET devices. Although the decrease of the drain current in halo structure MOSFET is usually explained in terms of the increase of the threshold voltage, more decrease in the drain current than is predicted by the increased threshold voltage has experimentally been observed. In this work, the effect of halo doping profile on the drain current degradation is investigated in terms of the field distribution along the channel. Effective mobility model of the halo MOSFETs due to pocket implantation is presented and the degradation of the mobility is shown to be effective in the further decrease of the drain current. Present model is shown to be in good agreement with experimental results.

• Journal of IKEEE
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• v.21 no.1
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• pp.96-99
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• 2017

In this study the influence of the random dopant fluctuation (RDF) depending on the halo and LDD implantations for the metal-oxide-semiconductor field effect transistor is investigated through the 3D atomistic device simulation. For accuracy in calculation, the kinetic monte carlo method that models individual impurity atoms and defects in the device was applied to the atomistic simulation. It is found that halo implantation has the greater influence on RDF effects than LDD implantation; three-standard deviation of $V_{TH}$ and $I_{ON}$ induced by halo implantation is about 6.45 times and 2.46 times those of LDD implantation. The distributions of $V_{TH}$ and $I_{ON}$ are also displayed in the histograms with normal distribution curves.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2014.11a
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• pp.127-129
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• 2014

In image dehazing, the existing transmission estimators bring out the halo artifact at boundaries unless they adopt a refinement process with the high computational complexity. We analyze how the existing transmission estimation methods suffer from the halo artifact at the boundaries and observed that the elaborate, high computational refinement processes to remove the halo effect are excessive for dehazing. On the basis of the analysis and observation, we embed a simple segmentation logic in an existing transmission estimator, which is sufficiently accurate for dehazing. The experiment verifies that the proposed method significantly reduces the halo artifact without requiring any refinement process.