• KIISE Transactions on Computing Practices
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• v.21 no.1
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• pp.40-45
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• 2015

Online social networks(OSN) are very popular nowadays. As OSNs grows, the commercial markets are expanding their social commerce by applying Influence Maximization. However, in reality, there exist more than two players(e.g., commercial companies or service providers) in this same market sector. To address the Influence Maximization problem between adversaries, we first introduced Influence Maximization against the social adversaries' problem. Then, we proposed an algorithm that could efficiently solve the problem efficiently by utilizing social network properties such as Betweenness Centrality, Clustering Coefficient, Local Bridge and Ties and Triadic Closure. Moreover, our algorithm performed orders of magnitudes better than the existing Greedy hill climbing algorithm.

• Journal of the Korean Solar Energy Society
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• v.28 no.6
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• pp.48-57
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• 2008

The research analyzed the distribution of the indoor temperatures of a radiant floor cooling system through mock-up experiments. It investigated the temperature difference of feed water, the vertical temperature difference of indoor air, the temperature difference of floor surface, and so on. The following is the results of the research. First, the research shows that the difference between indoor temperature and outside temperature was the smallest when the temperature of feed water was set at 16$^{\circ}C$. In addition, the temperature changes according to indoor positions (wall, room, floor, and ceiling) were the most uniform. Thus, the research found that the cold water temperature of 16$^{\circ}C$ is the most proper. In addition, it confirmed that the feed water temperature of 18$^{\circ}C$ is effective because the temperature can lower the temperature of a room to 13.55$^{\circ}C$, which is lower than the temperature of a non-cooling mode. Second, an investigation on the temperature distribution of vertical air in indoor space shows that the temperature distribution had a difference of 0.2 to 1.9$^{\circ}C$ on the average, which satisfies the range of 3.0$^{\circ}C$ in the standard of ISO.

• Journal of the Korea Organic Resources Recycling Association
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• v.22 no.2
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• pp.44-49
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• 2014

In order to remove the heavy metals from synthetic wastewater containing Pb, Cr, and Cd, the experiment was conducted with a variety of concentration and pH by using the washed and dried coffee grounds as adsorbent. Almost of the heavy metals were removed in thirty minutes and the removal efficiency was maximized to the 80 percents following the different pH conditions. Furthermore, in the case of Cr, the removal efficiency was declined with the increasing of pH. As a result of this study, coffee grounds is proved to be a very good adsorbent to remove the heavy metals.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.4
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• pp.648-662
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• 1996

Electrode surface reaction on glassy carbon and synthesized graphite (PVDF mixed graphite) in sulfuric acid solution is investigated by impedance spectroscopy at cyclic polarization. The redox peak, which may be due to the change of chemical adsorped functional group on electrode surface or oxidation and reduction of oxygen, is represented on glassy carbon and graphite electrode in potentio-dynamic current curve. The oxidation and reduction of these surface functional group on glassy carbon and PVDF mixed graphite have a major affect on the impedance spectrum and Faraday impedance parameter at cyclic polarization.

• Journal of Korean Society for Atmospheric Environment
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• v.24 no.1
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• pp.100-107
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• 2008

The objective of this study was to quantitatively estimate PM-10 source contribution in Gumi City, Korea. Ambient PM-10 samples were collected by a high volume air sampler, which operated for 84 different days with a 24-h sampling basis, from June 14,2001 though May 19, 2003. The filter samples were analyzed for determining 13 inorganic elements, 3 anions, and a total carbon. The study has intensively applied a receptor model, the PMF (Positive Matrix Factorization) model. The results from PMF modeling indicated that a total of seven sources were independently identified and each source was contributed to the ambient Gumi City from secondary sulfate (34%), motor vehicle (26%), soil relation (5%), field burning (3%), industrial relation (3%), secondary nitrate (22%), and incinration (7%) in terms of PM-10 mass, respectively.

• Proceedings of the KOSOMBE Conference
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• v.1993 no.11
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• pp.104-106
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• 1993

Some cardio-vascular assist systems need more inexpensive artificial heart valves for short-term use. To meet with this need, we have developed a new polymer valve that is very simple to manufacture and of which its dimensions are easy to change, depending on its application. We have tested the hydrodynamic performance of the new polymer valve using a mock circulatory testing system and studied the flow through the valve using high-speed camera combined with image processing techniques. The results show that this valve is superior in its performances to the other valves (Bjork-Shiley mechanical valve and trileaflet polymer valve) and have no stagnation points. We also have tested the hemolytic potential of the valve. The valve is less hemolytic than the Bjork-shiley mechanical valve finally, we have applied this valve to a left ventricular assist device that we are developing.

• KSBB Journal
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• v.8 no.3
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• pp.230-236
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• 1993

A Chitulose film was made by dissolving chitin and cellulose in a dimethylacetamide/LiCl solvent system This film was completely degraded in 20 days in soil and penetrated by soil microorganisms in 16-26 hours. A permeability analysis of the film showed that water permeability was in the range of 0-187.5 $1/m^2$/day, depending upon the ratio of chitin to cellulose and decreased with increasing a cellulose content in the Chitulose film The permeabilities of organic compounds, $Na^+$ and oxygen change with the composition of the Chitulose file The film was tested with a burned 2~3degree rat for exploring its use as artificial skin. The rat was completely cured within 31 days without inflammation.

• Journal of Chest Surgery
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• v.30 no.6
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• pp.617-620
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• 1997

Traumatic aneurysm of both the thoracic aorta and the left ventricle are extremely rare in children because it is characterized by high mortality. We report a case which we experienced recently with sucessful outcome. A Five-year-old boy had a blunt trauma by bongo bus. He had pulmonary hemorrage and pericardial effusion complicated by multiorgan failure threatening his life. Aneurysm of LV and Descending aorta were showed by 2-D echocardiogram and MRI. The atient underwent successful corrective surgery 2 and half momths after trauma, the Postoperative status of this patient was uneventful, now he is being followed up the OPD.

• Journal of the Korea Society of Computer and Information
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• v.11 no.4 s.42
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• pp.9-15
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• 2006

In this paper we propose Wilcoxon test, Median test and Van der Waerden test such as linear rank tests in two-sample location problem for detecting edges effectively in noisy images. These methods are based on detecting image intensity changes between two pixel neighborhoods using an edge-height model to perform effectively on noisy images. The neighborhood size used here is small and its shape is varied adaptively according to edge orientations. We compare and analysis the performance of these statistical edge detectors on both natural images and synthetic images with and without noise.

• Textile Coloration and Finishing
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• v.30 no.4
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• pp.275-287
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• 2018

In recent years, research on the development of eco-friendly synthetic suede based on water-dispersed polyurethane resin and non-fluorine water repellent has been conducted. Synthetic suede has a problem that the fastness to dyeing is greatly lowered after the water-repellent processing at a high temperature of $160^{\circ}C$ because the polyester is dyed with a disperse dye. Therefore, in this study, silica was added to water-dispersed polyurethane resin to improve dye fastness. To distribute the $PUD-SiO_2$ mixture evenly in the water-dispersed polyurethane resin, sufficient stirring was done for a period of time. When the $PUD-SiO_2$ mixture(PUD 1-5%) is applied to the substrate, it is confirmed through SEM that the mixture is uniformly applied without particle condensation. The results showed that silica with a diameter of 4~12nm and BET of $200{\sim}380g/m^2$ had the ability to improve dispersibility and fastness.