• 한국재료학회지
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• 제13권10호
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• pp.640-644
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• 2003

NiCr thin films were fabricated by rf magnetron sputtering for applying to both the top electrode and absorption layer on Pb(Zr, Ti)O$_3$(PZT) thin films for infrared sensors. The rms roughness and resistivity of NiCr films prepared with Ni power of 80 W and Cr power of 50 W showed the most stable oxidation resistance after annealing at $600^{\circ}C$ for 5 min in oxygen ambient. The rms roughness and resistivity of NiCr films annealed at $V^{\circ}C$ in oxygen ambient were about 2$0\AA$ and $70 \mu$Ω-cm, respectively. As-deposited Ni/PZT/Pt and NiCr (Ni 80 W, Cr 50 W)/PZT/Pt structures showed well saturated hysteresis loops. However, in case of the samples annealed at $500^{\circ}C$ in oxygen ambient, only NiCr/PZT/Pt showed saturated loops having a remanent polarization of 20$\mu$C/$\textrm{cm}^2$. Ultra-thin NiCr films showed a possibility as a top electrode for infrared sensors.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.209-210
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• 2006

We have successfully termed brown colored patterns inside of a transparent borosilicate glass generally known as BK7, laying the focus of near infrared Ti: sapphire femtosecond laser beam in the bulk BK7 glass. It is important to keep the laser power well below the damage threshold of BK7 in forming the color center. Thanks to the low laser power, there was no laser induced mechanical damage such as cracks or threads in the color formed area. From the absorbance spectrum and its gaussian fitting, we found the band gap of BK7, 4.21eV, and three absorption edges.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2018년도 춘계학술대회 논문집
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• pp.50.2-50.2
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• 2018

The demand for steady and dependable power sources is very high in the field of sustainable energy because of the limited amount of fossil fuels reserves. Among several sustainable alternatives, solar energy may be the most efficient solution because it constitutes the largest renewable energy source. So far, the only practical way to store such large amounts of energy has been to use a chemical energy carrier likewise a fuel. In various solar energy to power conversion systems, the photoelectrochemical (PEC) splitting of water into hydrogen and oxygen by the direct use of solar energy is an ideal process. It is a renewable method of hydrogen production integrated with solar energy absorption and water electrolysis using a single photoelectrode. Previous studies on photoelectrode films for PEC water splitting cells have been mainly focused on synthesizing oxide semiconductors with wide band gaps, such as TiO2(3.2eV), WO3(2.8eV), and Fe2O3(2.3eV). Unfortunately, these pristine oxide photoanodes without any catalysts have relatively low photocurrent densities because of the inherent limitation of insufficient visible light absorption due to the wide bandgap. Specifically, there is a tradeoff between high photocurrent and photoelectrochemical corrosion behavior, which is representative of figures of meritf or PEC materials.

• 동력기계공학회지
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• 제20권5호
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• pp.86-91
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• 2016

This paper is concerned chiefly with the method of porous foam manufacture using basalt stone powder sludge. The hydrogen peroxide($H_2O_2$) of bloating agent has lots of problems to manufacture porous lightweight aggregate due to fast reaction rate with cement or calcium hydroxide($Ca(OH)_2$). The $H_2O_2$ injecting method using nozzle for manufacturing porous lightweight aggregate is proposed, in this study. This method is to inject $H_2O_2$ at the pressure of 10 MPa on upper side of slurry mixing materials such as stone powder sludge and quick-lime(CaO) by injector. The specimen was dried in furnace at $100^{\circ}C$ for 1 hour and cured at ambient temperature for 30 days. We analyzed the characteristics including specific gravity and water absorption. The experiments were found that the porous foam has low specific gravity, high water absorption and uniform distribution of porous more than manufactured foam by general bloating methods.

• Advances in concrete construction
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• 제4권4호
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• pp.231-242
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• 2016

The major problem of a coal combustion-based power plant is that it creates large quantity of solid wastes. So, to achieve the gainful use of waste materials and to avoid other environmental problems, this study was undertaken. The quantity of coal ash by-products, particularly coal fly ash and coal bottom ash has been increasing from the coal power plants around the world. The other objective of this study was to explore the possibility of utilization of coal ash in the production of ash bricks. In 15 different mixes, Mix Designation M-1 to M-15, the varying percentages of lime and gypsum were used and sand was replaced with coal bottom ash. Further, it has been noticed that the water absorption and compressive strength of mix M-15 is 13.36% and 7.85 MPa which is better than the conventional bricks. The test results of this investigation show that the prism strength of coal ash masonry prisms was more than that of the conventional bricks.

• 한국식품조리과학회지
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• 제19권4호
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• pp.447-453
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• 2003

This study was done to provide the basic information of bread made with curry powder. The amounts of curry powder used were 0 to 3% based on the wheat flour weight. The quality of bread was investigated by evaluation of the specific loaf volume, water absorption capacity, color, sensory quality and texture. The weight of bread decreased with the increase of curry power contents, but there were no significant differences among 0.5, 1 and 2% added curry powder bread. The volume and specific loaf volume also decreased with the increase of curry power contents, but those decreases were not significant between 1% one and 2% one. The water absorption capacities were not affected by the addition of curry powder. The lightness and redness decreased with an increase of curry powder content in the bread, while yellowness increased significantly(p<0.01). The result of the sensory evaluation showed that total acceptabilities of appearance, aroma, texture and taste in the bread with 0.5% and 1% curry powder were significantly higher than the control group and the other groups. Overall quality was negatively affected by the yellowness, odor, hot and bite taste of added curry powder. The factors affecting on the overall quality of the bread with added curry powder were in order of taste quality > curry powder odor > texture quality > aroma quality > springiness > wheat flour odor.

• 방사선산업학회지
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• 제11권3호
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• pp.139-144
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• 2017

To evaluation of clinical usefulness for B1+RMS limits, we compared image quality of Routine, Specific absorption rate (SAR) and Root mean square (RMS) protocol. 5 volunteers underwent Magnetic Resonance Imaging (MRI) scan of the brain using three different protocols. We draw Region of interest ROI in cortex, white matter, gray matter, putamen and thalamus of axial plan. Signal to noise ratio (SNR) were evaluated in each area and Contrast to noise ration (CNR) were evaluated between white matter and gray matter. Qualitative evaluation was used to score each ROI. B1+RMS is confirmed its usefulness compared to conventional SAR standard on the aspect of improvement of image quality, reduction of scan time and easy adjusting parameter.

• 방사성폐기물학회지
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• 제18권4호
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• pp.481-496
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• 2020

After nuclear power plants are permanently shut down and decommissioned, the remaining irradiated metal components such as stainless steel, carbon steel, and Inconel can be used as neutron absorber. This study investigates the possibility of reusing these metal components as neutron absorber materials, that is burnable poison. The absorption cross section of the irradiated metals did not lose their chemical properties and performance even if they were irradiated over 40-50 years in the NPPs. To examine the absorption capability of the waste metals, the lattice calculations of WH 17×17 fuel assembly were analyzed. From the results, Inconel-718 significantly hold-down fuel assembly excess reactivity compared to stainless steel 304 and carbon steel because Inconel-718 contains a small amount of boron nuclide. From the results, a 20wt% impurity of boron in irradiated Inconel-718 enhances the excess reactivity suppression. The application of irradiated Inconel-718 as a burnable absorber for SMR core was investigated. The irradiated Inconel-718 impurity with 20wt% of boron content can maintain and suppress the whole core reactivity. We emphasize that the irradiated metal components can be used as burnable absorber materials to control the reactivity of commercial reactor power and small modular reactors.

• 대한후두음성언어의학회지
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• 제32권2호
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• pp.51-55
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• 2021

There are several lasers available for office-based or suspension microlaryngoscopy laser procedures in the treatment of laryngeal diseases. Each has advantages and disadvantages given the depth of penetration per unit of power, absorption in water, spectral absorption characteristics, mode of delivery, safety, and cost. It is important to note that while the proper selection of indication of treatment based on a laser wavelength is critical, of equal importance is selecting the appropriate power setting, focal length (or spot size), and time of exposure. The photoangiolytic lasers precisely target hemoglobin within the microcirculation of the highly vascularized tissue and may have better hemostatic effects and preservation of surrounding normal tissue than the CO₂ laser. Although the choice of laser is purely theoretical and cannot be accurately concluded which parameters of laser (wattage and pulse width) were best to use, photoangiolytic laser surgery is safe and effective for specific laryngeal lesions. In this review, indications for photoangiolytic laser procedures for various laryngeal diseases, laser settings and surgical techniques for specific laryngeal lesions including sulcus vocalis, laryngeal dysplasia, and recurrent respiratory papillomatosis will be introduced. Pros and cons of in-office laser surgery using photoangiolytic laser and flexible CO₂ laser will also be addressed.

• 유통과학연구
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• 제10권11호
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• pp.61-70
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• 2012

Purpose - The entry of Super Supermarkets (SSM), operated by large corporations, into the retail distribution market weakens the competitive power of local supermarkets (SM) and their families leading to a rapid collapse of the local-SM market. Accordingly, this is a very sensitive and urgent issue in Korean society and politics. Therefore, the government is required to take steps to activate a local-SM market and regain the loyalty of their customers. However, in spite of the urgent need of a comparative study on the advantages and competitive power of local-SM in relation to the SSM, little research has been done on this issue to date. One purpose of this study is to analyze the differences in store characteristics of the local SM and SSM, and to explore the relationships amongst various store characteristics, such as consumption emotion, relation quality, and store loyalty between store types to provide an efficient solution to activate a local-SM market. Research design, data, methodology - To analyze the differences in the evaluation of store characteristics between store types, and to test the moderator and mediator effects, data were collected from 488 customers in Seoul, Incheon,and Gyeonggi Province. The theoretical model consists of four hypotheses, and data was processed to test these using factor analysis, t-test, regression analysis, hierarchical regression, and the three step regression proposed by Baron and Kenny. Results - First, the analysis shows that local-SM customers evaluate location characteristic factors significantly higher compared to SSM customers. However, SSM customers evaluate quality of merchandise, sales promotion activities, and store environment significantly higher. Yet, there are no significant differences in the evaluation of consumption emotion, relation quality,and store loyalty between the store types. Second, the analysis of moderator effects of the store type show that sales promotion and store atmosphere factors have a significantly negative moderating effecton positive consumption emotion, while positive consumption emotion has a significantly positive moderating effect on absorption of relation quality, while there are no significant moderating effects between consumption emotion and store loyalty. Third, while both trust and absorption of relation quality are partially mediated between consumption emotion and store loyalty, only absorption is partially mediated between positive consumption emotion and store loyalty. There are no significant mediating effects of absorption between negative consumption emotion and store loyalty. Conclusions - We strongly recommend that location restrictions on entrance of SSM into local-SM market should either be further strengthened or sustained for the activation of the local store market. Government should strengthen financial support to improve the quality of merchandise, sales promotion, employee education, store environment of the local-SM by providing appropriate business consulting. Moreover, the result implies that the owners of alocal-SM should take measures to increase customers' absorption and store loyalty, such as store cleanliness, maintaining a delightful atmosphere at the store, and training employees on attitudes towards customers. As this study is restricted within Seoul, Incheon, and Gyeonggi Province, care needs to be taken in generalizing the interpretation and application to the national level.