• Journal of Wetlands Research
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• v.15 no.3
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• pp.367-380
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• 2013

In this study, sub-indicators, and thematic mid-indexes to evaluate the water use characteristics were selected through historical data analysis and factor analysis, and consisted of the subject approach framework. And the integrated index was developed to evaluate water use characteristics of the watershed. Using developed index, the water use characteristics were assessed for 812 standard basins with the exception for North Korea using data of 1990 to 2007 from the relevant agencies. A sensitivity analysis is conducted for this study to determine the proper way through various normalization and weighting methods. To increase the objectivity of developed index, the history of the damage indicators are excluded in the analysis. In addition, in order to ensure its reliability, results from index with and without consideration of the damage history were compared. Also, the index is also applied to real data for 2008 Gangwon region to verify its field applicability. Through the validation process this index confirmed the adequacy for the indicators selection and calculation method. The results of this study were analyzed based on the spatial and time vulnerability of the basin's water use, which can be applied to various parts such as priority decision-making for water business or policy, mitigations for the vulnerable components of the basin, and supporting measures to establishment by providing relevant information about it.

• Korean Journal of Food Science and Technology
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• v.34 no.3
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• pp.400-406
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• 2002

In case of doenjang, solution of browning problem might be an important remedy in order to dissolve consumers' dissatisfaction, therefore this study was performed to develop traditional doenjang which has improved in color aspect for consumers' needs. Physicochemical compositions and color values of commercialized traditional doenjang which was processed by history references of our country, were analyzed. doenjang used as samples were processed with traditional meju, which were made with soybean and mixed with various rates after following process such as soaking, steaming, cooling, chopping and grinding. The doenjang processed were storaged at $30^{\circ}C$ for 27 days, and their amino-N, pH, color values and sensory evaluation were analyzed with fermentation period. Furthermore, nitrogen results analyzed were compared with that of commercialized traditional doenjang. In the comparison with control, treated with only traditional meju, and doenjang treatments processed with different mixing rates of traditional meju and steamed soybean, the content of amino-N in control were higher than the others, and the contents of amino-N decreased with increasing contents of steamed soybean. Their pH were changed weak alkalic region into weak acidic region with fermentation period. In the aspect of color, traditional doenjang having the rate of traditional meju and steamed soybean (1:4) was most improved and also, in comparison of result of sensory evaluation with commercial traditional doenjang, its color, taste and falvor were evaluated predominent, therefore it might be thought to have competition on the market.

• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.935-940
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• 2002

Effects of changes in the margarine content and the number of layers of the puff pastry on the color, hardness, and hardness change during storage of the final products were investigated. At equal content of pastry margarine, the lightness of the crust decreased slightly as the number of layers increased. Redness of the puff pastry with 70% margarine content and 81 layers was $16.8{\pm}2.3$ and yellowness of puff pastry with 70% margarine content and 256 layers was 26. No significant differences were observed in the crumb change of the samples. The puff pastry with 90% margarine content and 144 layers showed the lowest hardness of $839.6{\pm}75.6g$. Hardness of the products storage period increased significantly as the number of layers increased at equal pastry margarine content, whereas with same number of layers, decreased gradually as pastry margarine content increased. Results of the sensory evaluation reveal that the puff pastry with 90% margarine content and 144 layers was better than other samples. These results show the important of selecting the optimum number of layers during the manufacturing process to obtain the optimum condition for the mouthfeeling, flavor and overall acceptability of final products.

• Resources Recycling
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• v.29 no.1
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• pp.81-88
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• 2020

Recovery of gallium and indium from waste light emitting diodes has been emphasized gradually owing to high content of gallium and indium. This study was established the recovery of gallium (Ga³⁺) and indium (In³⁺) from waste gallium nitride was contained in waste light-emitting diodes. The procedure was divided into the following steps; characteristic analysis, alkaline roasting, and leaching. In characteristic analysis part, the results were used as a theoretical basis for the acid leaching part, and the chemical composition of waste light emitting diodes is 70.32% Ga, 5.31% Si, 2.27% Al and 2.07% In. Secondly, with reduction of non-metallic components by alkaline roasting, gallium nitride was reacted into sodium gallium oxide, in this section, the optimal condition of alkaline roasting is that the furnace was soaked at 900℃ for 3 hours with mixing Na₂CO₃. Next, leaching of waste light emitting diodes was extremely important in the process of recovery of gallium and indium. The result of leaching efficiency was investigated on the optimal condition accounting for the acid agent, concentration of acid, the ratio of liquid and solid, and reaction time. The optimal condition of leaching procedures was carried out for 2.0M of HCl liquid-solid mass ratio of 30 ml/g in 32minutes at 25℃ and about 96.88% Ga and 96.61% In were leached.

• Polymer(Korea)
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• v.38 no.1
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• pp.31-37
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• 2014

To prepare biomass based nylon 6,5 copolymers, ${\varepsilon}$-caprolactam and 2-piperidone, the monomers of nylon 6,5 copolymers, were synthesized respectively from lysine and 5-aminovaleric acid which were produced from glucose by the fermentation process. The copolymers were then polymerized by the anionic ring opening polymerization of them at $40^{\circ}C$, using potassium tert-butoxide as a catalyst and acetyl-2-caprolactam and carbon dioxide as initiators. The prepared copolymers were characterized with various analytical methods: their viscosity molecular weight ($M_{\eta}$) was as high as 30000 g/mol and polymerization yield was over 50%, and it was found that they were semi-crystalline polymers having melting point at $165^{\circ}C$ which was much lower than its thermal degradation point, $250^{\circ}C$. These polymers were expected to have good thermal processability and application fields.

• Korean Journal of Optics and Photonics
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• v.14 no.3
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• pp.331-337
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• 2003

This paper represents 50 ㎓ narrow band pass filters for fiber optical communication fabricated by dual ion beam sputtering method. We have analyzed the characteristics of the TA$_2$ $O_{5}$ and $SiO_2$ single layers in order to optimize the process conditions for the 50 ㎓ narrow band pass filters, and controlled the film thickness uniformity to less than 0.1 nm deviation by dual peak spike filter pre-deposition. We designed and fabricated 50 ㎓ narrow band pass filters that consist of 216 layers including 4 cavities based on quarter wave optical thickness. Class substrates with high thermal expansion coefficients were used to reduce the film stress. Anti-reflection coating at the rear side of the substrate was also needed to reduce the optical thickness errors of the Optical Monitoring System caused by multiple beam interference between the front side and the rear side of substrate. The optical characteristics of this 50 ㎓ narrow band pass filters are insertion loss of 0.40 ㏈, pass band ripple of 0.20 ㏈, and pass bandwidth at -0.5 ㏈ of 0.20 nm. and isolation bandwidth at -25 ㏈ of 0.6 nm, which satisfy specifications of dense WDM system in fiber optical communications.tions.

• Journal of Marine Life Science
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• v.4 no.2
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• pp.81-85
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• 2019

This study was carried out to observe the changes of seaweed community in artificial reefs installed in September, 2016 in Namae-ri, Yangyang-gun, and Seokbyeong-ri, Pohangsi, Korea. Field surveys were conducted by SCUBA diving once a season in February, May, August, and November of 2017, and quantitative survey and qualitative survey were carried out in parallel. In this study, a total of 94 species, including 11 green algae, 15 brown algae and 68 red algae were appeared. 66 species (8 green algae, 9 brown algae, 49 red algae) and 65 species (7 green algae, 9 brown algae, 49 red algae) were collected and identified in Yangyang and Pohang. In dominant species, Yangyang was dominant species of Saccharina japonica and subdominant species of Ulva australis. Pohang dominated in order of Colpomenia sinuosa and Gelidium elegans. In both coastal areas, Ulva spp., Colpomenia sinuosa were grown at the early stage of reforestation, and perennial seaweeds such as Saccharina japonica, Ecklonia cava and Gelidium elegans were grown. In order to clarify the clustering relation through flora change, it is necessary to monitor the transition process until the seaweed community is stabilized by observing the long-term change through continuous monitoring.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.32 no.3
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• pp.201-206
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• 2019

This report constitutes the first demonstration in Korea of single-crystal lateral gallium oxide ($Ga_2O_3$) as a metal-oxide-semiconductor field-effect-transistor (MOSFET), with a breakdown voltage in excess of 480 V. A Si-doped channel layer was grown on a Fe-doped semi-insulating ${\beta}-Ga_2O_3$ (010) substrate by molecular beam epitaxy. The single-crystal substrate was grown by the edge-defined film-fed growth method and wafered to a size of $10{\times}15mm^2$. Although we fabricated several types of power devices using the same process, we only report the characterization of a finger-type MOSFET with a gate length ($L_g$) of $2{\mu}m$ and a gate-drain spacing ($L_{gd}$) of $5{\mu}m$. The MOSFET showed a favorable drain current modulation according to the gate voltage swing. A complete drain current pinch-off feature was also obtained for $V_{gs}<-6V$, and the three-terminal off-state breakdown voltage was over 482 V in a $L_{gd}=5{\mu}m$ device measured in Fluorinert ambient at $V_{gs}=-10V$. A low drain leakage current of 4.7 nA at the off-state led to a high on/off drain current ratio of approximately $5.3{\times}10^5$. These device characteristics indicate the promising potential of $Ga_2O_3$-based electrical devices for next-generation high-power device applications, such as electrical autonomous vehicles, railroads, photovoltaics, renewable energy, and industry.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.1-7
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• 2018

In a microcolumn, a miniaturized electrostatic deflector is often adopted to scan an electron beam. Usually, a double octupole deflector is used because it can avoid excessive spherical aberrations by controlling the electron beam path close to the optical axis of the objective lens and has a wide scan field. Studies on microcolumns have been performed to improve the low throughput of an electron column through multiple column applications. On the other hand, as the number of microcolumns increases, the number of wires connected to the components of the microcolumn increases. This will result in practical problems during the process of connecting the wires to electronic controllers outside of the vacuum chamber. To reduce this problem, modified quadrupole and octupole deflectors were examined through simulation analysis by selecting an ultraminiaturized microcolumn with the Einzel lens eliminated. The modified deflectors were designed changing the size of each electrode of the conventional Si octupole deflector. The variations of the scan field and electric field strength were studied by changing the size of active electrodes to which the deflection voltage was to be applied. The scan field increased linearly with increasing deflection voltage. The scan field of the quadrupole deflector and the electric field strength at the center were calculated to be approximately 1.3 ~ 2.0 times larger than those of the octupole deflector depending on the electrode size.

• Journal of Korean Medicine Rehabilitation
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• v.29 no.3
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• pp.35-49
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• 2019

Objectives The purpose of this research is to evaluate the effectiveness of moxibustion theraphy for frozen shoulder through systematic review and meta-analysis. Methods The effect of moxibustion for frozen shoulder was constructed as a key question to search randomized controlled trials (RCTs) in 16 databases without type of publication restriction. Results A total of 790 studies were searched and 22 RCTs were finally selected through primary and secondary selection/exclusion process. In most of the evaluation indexes used in each study, moxibustion treatment for shoulder pain was statistically significant compared with other treatments. A meta-analysis of effective rate in 10 studies comparing moxibustion with acupuncture and acupuncture showed a statistically significant effect of moxibustion treatment. And there was a significant effect on the improvement of the shoulder mobility, but the effect size of shoulder pain was no significant effect for shoulder pain reduction. In addition in the result of meta-analysis of 4 studies' effective rate comparing moxibustion with electronic acupuncture, the effect of moxibustion was significantly higher than that of electronic acupuncture in frozen shoulder. Conclusions Moxibustion therapy was effective in symptoms in patients with frozen shoulder. However because of the high risk of bias in the quality of the included studies, the applicability of this study seems to be limited. It is thought that future randomized controlled trials will need to be designed and performed by reviewing ways to minimize bias.