• Resources Recycling
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• v.27 no.2
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• pp.48-54
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• 2018

Batch ion exchange experiments of Au(III) were performed from ammonium chloride solution by employing strong anionic exchange resins (Amberlite IRA 402 and AG 1-X8). Au(III) was well loaded into the two resins and the loading behavior of Au(III) into AG 1-X8 was superior to that into Amberlite IRA 402. The loading of Au(III) into AG 1-X8 followed Langmuir adsorption isotherm and the experimentally determined loading capacity was 355 mg/g. Au(III) was successfully eluted by $HClO_4$ from the loaded AG 1-X8 and the elution percentage of Au(III) increased with the concentration of $HClO_4$.

• Journal of Microbiology and Biotechnology
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• v.33 no.1
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• pp.135-141
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• 2023

Protection of skin cells from chronic infrared-A (IRA) irradiation is crucial for anti-photoaging of the skin. In this study, we investigated the protective activity of Rg3(S) and Rg3(S)-incorporated anionic soybean lecithin liposomes (Rg3/Lipo) with a size of approximately 150 nm against IRA-induced photodamage in human fibroblasts. The formulated Rg3/Lipo showed increased solubility in aqueous solution up to a concentration of 200 ㎍/ml, compared to free Rg3(S). In addition, Rg3/Lipo exhibited superior colloidal stability in aqueous solutions and biocompatibility for normal human dermal fibroblasts (NHDFs). After repeated IRA irradiation on NHDFs, elevated levels of cellular and mitochondrial reactive oxygen species (ROS) were greatly reduced by Rg3(S) and Rg3/Lipo. In addition, cells treated with Rg3/Lipo exhibited noticeably reduced apoptotic signals following IRA irradiation compared to untreated cells. Thus, considering aqueous solubility and cellular responses, Rg3/Lipo could serve as a promising infrared protector for healthy aging of skin cells.

• Journal of Korean Library and Information Science Society
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• v.45 no.4
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• pp.185-205
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• 2014

This study investigated IRA's 3 standards related to reading instruction and examined the value which can be meaningful to Korean situation. IRA divided reading educators into 7 types and proposed each detailed professional standard through the 'Standards for reading professionals'. The next standard called 'Standards for the English language art' described their direction and content for English language education including reading instruction. The 'Standards for the assessment of reading and writing' aims at the basis to evaluate students' reading ability. The value found through these standards is as follow: IRA's reading professionals standard can be a useful way to define the type of reading educator in Korea. A reading instruction standard like IRA's language art standard can guide reading instruction of Korean libraries in a more systemic and consistent way. A valid evaluation standard to measure students' reading ability can show the possibilities to define the students who struggle with reading and to provide more suitable instruction for them.

• Journal of Life Science
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• v.14 no.5
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• pp.794-799
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• 2004

Cyclodextrin glucanotransferase (CGTase) produced by Bacillus subtilis NAl/pKBl was used for the production of cyclodextrin (CD). The enzyme was purified by ion exchange and gel filtration chromatography. The purified enzyme exhibited its maximum activity in the pH range of 6.0 to 7.0 and temperature range of 60 to $70^{\circ}C$. Immobilization of purified CGTase was carried out with various immobilization matrices. Amberlite IRA-900, a strong basic anion exchange resin, showed the highest immobilization ability (38 units per gram resin). Optimal pH and temperature for enzymatic reaction of the immobilized CGTase were pH 6.0 and 60t. The activity of immobilized CGTase maintained more than a month and could be reused for a month in a continuous enzyme reactor for the production of CD.

• Journal of the Korean Chemical Society
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• v.42 no.2
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• pp.172-176
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• 1998

An anion exchange resin which has Alizarin Red S (ARS) as functional group was prepared by batch method. The resin is stable in acidic solutions below 0.5 M hydrochloric acid, nitric acid and sulfuric acid and adsorption capacity of Fe(Ⅱ) ion on the resin was larger than other metal ions. The preconcentration and the separation of Fe(Ⅱ) ion from the mixture solution were carried out with the pH 4.5 buffer solution and 0.1 M $HNO_{3}$ as eluents.

• Korean Management Science Review
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• v.13 no.3
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• pp.49-73
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• 1996

Common problems have been observed in the existing Information Requirements Analysis (IRA) methodologies such as BSP(IBM), CSF(Rockart), or ISP(Information Engineering), etc. These methodologies require too much time and human resources for the IRA process, involves high complexity, and their IRA outcomes are frequently biased by the subjective views of the people involved. In this paper, we introduce a new methodology for the enterprise wide information requirements analysis utilizing templates and nine closed-ended questions. Extending the BIAIT(Business Information Analysis and Integration Technique) method, this methodology presents nine question about each firm's order type(7Q's for customer side and 2Q's for supplier side) to derive information processing characteristics of the firms. As the central component of this methodology, data and process templates for the manufacturing industry were established. To validate the methodology, suitability of the data and process templates were examined through six real world business cases.

• Applied Biological Chemistry
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• v.26 no.4
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• pp.222-230
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• 1983

This study was designed to develop a process for the immobilization of xylose isomerase(D-xylose ketol isomerase, EC 5.3.1.5) from Streptomyces griseolus previously isolated by the authors and its application on a pilot plant scale for the production of high fructose corn syrup. The biomass which has endo-excreted xylose isomerase was homogenized under a pressure of $500kg/cm^2$ and 90.8% of the enzyme recovery of the native activity was obtained as compared to 54.7% recovery by the lysozyme treatment. Ionic bonding method was adopted for the enzyme immobilization due to its many reported merits. It was found that the porous resins such as Diaion HP 20, Duolite A-7, Amberlite IRA 93 and 94 were effective in immobilizing the enzyme. In addition, it was disclosed that the regeneration form of $BO_4--$ is effective for Amberlite IRA 93 and $HCO_3-$ for Diaion HP 20. Optimal immobilization condition for Amberlite IRA 93 was pH 8.0 and $55^{\circ}C$ yielding 80.6% of immobilization. Activity decay test showed half life of the immobilized enzyme with Amberlite IRA 93 was more than 24 days at $65^{\circ}C$. The carrier was evaluated to be resuable and its result showed the relative immobilization yields were 98.2, 93.3, 90.7 and 87.5%, respectively at second, third, forth and fifth rebinding test of the enzyme on Amberlite IRA 93. Optimal temperature of the immobilized enzyme was slightly lowered and the range widened to $60\sim70^{\circ}C$, while optimal pH moved toward $8.0\sim8.3$ in its isomerization reaction. The trial production result of high fructose corn syrup in pilot scale immobilization showed that one liter of immobilized xylose isomerase (350 IXIU/ml-R) is capable producing about 293l high fructose corn syrup(75% dry substance) in 30 days.

• Korean Journal of Remote Sensing
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• v.27 no.5
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• pp.507-520
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• 2011

Conventional radar altimeter system measured directly the distance between the satellite and the ocean surface and frequently used by aircraft for approach and landing. The radar altimeter is good at flat surface like sea whereas it is difficult to determine precise three dimensional ground coordinates because the ground surface, unlike ocean, is very indented. To overcome this drawback of the radar altimeter, we have developed and validated the interferometric radar altimeter signal processing which is combined with new synthetic aperture and interferometric signal processing algorithm to extract precise three-dimensional ground coordinates. The proposed algorithm can accurately measure the three dimensional ground coordinates using three antennas. In a set of 70 simulations, the averages of errors in x, y and z directions were approximately -0.40 m, -0.02 m and 4.22 m, respectively and the RMSEs were about 3.40 m, 0.30 m and 6.20 m, respectively. The overall results represent that the proposed algorithm is effective for accurate three dimensional ground positioning.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.11a
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• pp.123-123
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• 2004

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.26 no.1
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• pp.81-87
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• 2015

We present an implementation result of a computer GUI-based simulator using MATLAB to verify the performance of interferometric radar altimeter(IRA) which is possible to measure the slant range altitude and the cross-track angle to the nearest point for terrain aided navigation(TAN). After a brief description of the principle of TAN and IRA, we present that the grids are divided for the modeling of the reflected signal in digital elevation map(DEM) and so the radar cross section(RCS) of each grid is calculated and the signal-noise ratio(SNR) of the reflected signal in the radar beam width. And the signal processing procedures of the IRA and the structure of the IRA simulator are shown.