• Korean Journal of Remote Sensing
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• v.22 no.6
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• pp.507-518
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• 2006

The radiation at $11{\mu}m$ absorbed more than at $12{\mu}m$ when aerosols is loaded in the atmosphere, whereas it will be the other way around when cloud is present. The difference of the two channels provides an opportunity to detect aerosols such as Yellow Sand even with the presence of clouds and at night. However problems associated with this approach arise because the difference can be affected by various atmospheric and surface conditions. In this paper, we has analyzed how the threshold and sensitivity of the brightness temperature difference between two channel (BTD) vary with respect to the conditions in detail. The important finding is that the threshold value for the BTD distinguishing between aerosols and cloud is $0.8^{\circ}K$ with the US standard atmosphere, which is greater than the typical value of $0^{\circ}K$. The threshold and sensitivity studies for the BTD show that solar zenith angle, aerosols altitude, surface reflectivity, and atmospheric temperature profile marginally affect the BTD. However, satellite zenith angle, surface temperature along with emissivity, and vertical profile of water vapor are strongly influencing on the BTD, which is as much as of about 50%. These results strongly suggest that the aerosol retrieval with the BTD method must be cautious and the outcomes must be carefully calibrated with respect to the sources of the error.

• Clean Technology
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• v.29 no.3
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• pp.217-226
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• 2023

The amount of hydrogen adsorbed in arrays of single walled carbon nanotubes (SWNTs) was studied as a function of nanotube diameter and distance between the nearest-neighbor nanotubes on square arrangements using a grand canonical Monte Carlo simulation. The influence of the geometry of a triangle array with the same diameters and distances was also studied. Hydrogen-carbon and hydrogen-hydrogen interactions were modeled with Lennard-Jones potentials for short range interactions and electrostatic interactions were added for hydrogen-hydrogen pairs to consider quantum contributions at low temperatures. At 194.5 K, Type I isotherms for large-diameter SWNTs and Type IV isotherms without hysteresis between adsorption and desorption processes for wider tube separations were observed. At 200 bars, the gravimetric hydrogen storage capacity of the SWNTs was reached or exceeded the US Department of Energy (DOE) target, but the volumetric capacity was about 70% of the DOE target. At 77 K, a two-step adsorption was observed, corresponding to a monolayer formation step followed by a condensation step. Hydrogen was adsorbed first to the inner surface of the nanotubes, then to the outer surface, intratubular space and the interstitial channels between the nanotube bundles. The simulation indicated that SWNTs of various diameters and distances in a wide range of configurations exceeded the DOE gravimetric and volumetric targets at under 1 bar.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.35 no.1
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• pp.1-12
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• 2023

Along with the growing interest in renewable energy development, Korea's west coast is one of the favorable regions for tidal power. Tidal power using tidal barrages that work like hydroelectric dams is a representative method of tidal power through long-term operation, but the promotion of tidal power projects is being delayed or stopped due to impacts on ecological changes, reproduction, water column processes and hydrology. In order to reduce the high construction cost and environmental cost problems caused by tidal power using tidal barrages, in this study, field experiments were conducted to develop and verify the performance of tidal power generation devices applicable to sea areas where dykes are already installed. As a result of conducting five cases of experiments using two water tanks, pipe lines, open channels, and water turbine and generator, the possibility of developing a power generation system capable of generating more than 10 kW output and more than 60% efficiency were confirmed. The results of this study can be used for small-scale tidal power by utilizing the existing dykes of the west coast.

• Korean journal of communication and information
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• v.61
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• pp.28-51
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• 2013

The present study analyzed the effects of brand extension on the existing parent brand by applying the media brand extension model which previous studies had suggested based on consumer based brand equity model. Based on previous studies, the present study constructed a research model in which pre-brand extension parent brand evaluation, brand portfolio quality variance, perceived number of brand extensions, perceived fit between parent brand and brand extended channel, and brand extended channel evaluation are supposed to affect post-brand extension brand extension evaluation, and tested the media brand extension feedback effects model through structural equation modeling. The analysis results show that pre-brand extension parent brand evaluation, brand portfolio quality variance, perceived fit, and brand extended channel evaluation affect post-brand extension parent brand evaluation while the effect of perceived number of brand extensions is not significant.

• Journal of the Mineralogical Society of Korea
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• v.27 no.2
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• pp.97-105
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• 2014

Artificial precipitation ponds, consisting of three steps of oxidation pond, successive alkalinity producing system (SAPS) and swamp, were constructed for the treatment of the acid mine drainage from the Iwal coal mine. The efficacies of the passive treatment system in terms of neutralization of mine water and removal of dissolved ions were evaluated by the chemical analyses of the water samples. Mine water in the mine adits was acidic, showing the pH value of 2.28-2.42 but the value increased rapidly to 6.17-6.53 in the Oxidation pond. The purification efficiencies for the removal of Al and Fe were 100%, whereas those of $SO_4$, Mg, Ca, and Mn were relatively low of 50%, 40%, 24%, and 59%, respectively. These results indicate a need for application of additional remediation techniques in the passive treatment systems. The precipitates that formed at the bottom of the mine water channels were mainly schwertmannite ($Fe_8O_8(OH)_6SO_4$) and those in the leachate water were 2-line ferrihydrite ($Fe_2O_3{cdot}0.5H_2O$).

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.6
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• pp.110-121
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• 2016

The primary aim of the color constancy algorithm is to estimate illuminant chromaticity. There are various statistical-based, learning-based and combinational-based color constancy algorithms already exist. However, the statistical-based algorithms can only perform well on images that satisfy certain assumptions, learning-based methods are complex methods that require proper preprocessing and training data, and combinational-based methods depend on either pre-determined or dynamically varying weights, which are difficult to determine and prone to error. Therefore, this paper presents a new optimization based illuminant estimation method which is free from complex preprocessing and can estimate the illuminant under different environmental conditions. A strong color cast always has an odd standard deviation value in one of the RGB channels. Based on this observation, a cost function called the degree of illuminant tinge(DIT) is proposed to determine the quality of illuminant color-calibrated images. This DIT is formulated in such a way that the image scene under standard illuminant (d65) has lower DIT value compared to the same scene under different illuminant. Here, a swarm intelligence based particle swarm optimizer(PSO) is used to find the optimum illuminant of the given image that minimizes the degree of illuminant tinge. The proposed method is evaluated using real-world datasets and the experimental results validate the effectiveness of the proposed method.

• CRM연구
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• v.4 no.1
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• pp.19-34
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• 2011

Recently, companies have interests in the adoption and diffusion of customer relationship management(CRM). And, as information and communication technologies and Internet technologies proliferate, they also have interests in e-CRM, which implements CRMusing online communication channels. Until now, many researchers have tried to identify the success factors of CRM and evaluate their relative importance. However, only a few studies have dealt with the success factors of e-CRM. For this reason, we aim at identifying and evaluating the success factors of e-CRM in order to provide the companies with the guideline for preparing the implementation of e-CRM. Our study adopts analytical hierarchy process(AHP) as a tool for evaluating these factors because it has been widely applied and validated for a long time. Whereas prior studies have analyzed the success factors from the organizational and technological perspective, our study analyzes them from the functional perspective. As a result, we found that the companies should manage all the CRM components including analytic-operational-collaborative CRM in good balance. Also, we found that the sufficient support from CEO, the acquisition of good quality customer data, and theonline processing capability for responding customers' requests effectively are important for the success of e-CRM.

• Journal of Distribution Science
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• v.15 no.10
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• pp.93-103
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• 2017

Purpose - Sports and the media have been developed together through a close relationship. During the past decade, the media landscape and the coverage of sports events have been changed. Sports fans can use the sports content at the time they want, on the platform they prefer. Furthermore, thanks to the advanced information technology, sports fans are likely to be more engaged in sport in communication technology-friendly stadium. However, the literature on the relationship between sports and the media has heavily focused on the differences of media types, clear distinction between media suppliers and consumers, and the limited media extension. Given the limitation of prior research, therefore, it has not fully reflected the change in society and culture, the importance of media recipients or consumers, and the mediating characteristic of the media. In order to generate further insights for sport media related industry and its society, it is necessary to comprehend the contemporary phenomena of real world situation in new media and sport and to discuss how new media influence sport and how their relationship is changing in managerial context. The purpose of this study is to identify new media cases as distribution channels in sports context and is to develop insights by discussing its role and meaning of new media in sport society. Research design, data, and methodology - The study employed the theory-centered review and case analysis. In order to explain phenomena of the role of new media in contemporary sport and to generate related insights in sport context, the study reviewed the new media cases applied in sport industry and interpreted their meaning by employing medium theory, remediation theory, and new media theory. Results - The study discussed the limitation of prior sport media research and identified the characteristics of sport as new media such as remediating, extending sensory organs, reiterating physical space and electronic space. Conclusions - The study derived the characteristics of sport as new media, in a sport setting, and through sports settings. Findings would assist to comprehend the role of new media in spectating sport and provide insights for sport media study.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.8 s.338
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• pp.33-40
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• 2005

This paper presents a structure of the searcher using a diversity in array antenna systems operating in the cdma2000 1x signal environments. The new technique exploits the fact that the In-phase and quadrature components of interferers can respectively be viewed as an independent gaussian noise at each antnna element in most practical cdma signal environments. The proposed PN acquisition scheme is a singles-dwell PN acquisition system consisting of two stages, that is, the searching stage and the verification stage. The searching stage independently correlates the receiver multiple signals with PN generator of each antenna element for obtaining the synchronous energy at the entire region. Then, the searching results of each antenna element are non-coherently combinind. The verification stage compares the searching energy with the optimal threshold, which is predesigned in the lock detector, and decides whether the acquisition is successful or fail. In this paper, we analyzed the effect of tile diversity order to determine the mean acquisition time. In general, it is known that the mean acquisition time significantly decrease as the number of antenna elements increases. But, as the diversity order goes up, the enhancement of the performance is saturated. Therefore, to decrease the mean acquisition time of the searcher, we must design the optimal array antenna systems by considering the operating SNR range of the receiver, the probability of detection $P_D$ and that of false alarm $P_{FA}$ . The Performance of the proposed PN acquisition scheme is analyzed in frequency selective Rayleigh fading channels. In this paper, the effect of the number of antenna elements on PN acquisition scheme is shown according to the probability of detection $P_D$ and that of false alarm $P_{FA}$.

• The Journal of Dong Guk Oriental Medicine
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• v.9
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• pp.127-138
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• 2000

The methods of checking the exuberance of yang (潛陽法) are a kind of medical treatments which cure various symtoms caused by hyperactivity of liver-yang, at the same time used for treating apoplexy. Thus, I investigated the application of checking the exuberance of yang to treat stroke. The conclusions are as follows. We can find application of checking the exuberance of yang to apoplexy on Synopsis of the Gold Chamber. After Ye Gui who persisted the theory of endogenous wind, many physicians applied the method of checking the exuberance of yang and this method has usually applied with nourishing yin. The methods of checking the exuberance of yang are concretely applied as follows. 1) a portion of apoplexy involving the channels and collaterals, which is caused by deficiency of yin and wind-fire pathogen. 2) excessive-syndrome of coma accompanied by heat syndrome. 3) epilepsy caused old apoplexy. The majority of shells for example abalone shell, hawksbill shell, oyster shell, tortoise-shell etc. are the most frequent use of herbal drug which check the exuberance of yang. The precriptions of checking the exuberance of yang are Ho-jam-hwan(虎潛丸), Ko-bon-dan(固本丹), Cheon-ma-gu-deung-eum(天麻鉤藤飮), Chin-gan-sik-pung-tang(鎭肝熄風湯) etc.