• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.3
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• pp.286-296
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• 2020

Sandwich structures are general-purpose structures that can reduce the structural weight of composite ships. Core materials are essential for these structures, with polyvinyl chloride (PVC) foams being the most popular. These foam core materials are subjected to various tests in the development process, and must satisfy the performance requirements of several ISO and ASTM standards. Therefore, a procedure for evaluating the performance of foam core materials was proposed in this paper. In addition, prototypes were fabricated using a commercial PVC foam core product in accordance with the structural design of an 11 m fiber-reinforced plastic yacht. Then, a case study was conducted on the proposed evaluation procedure. The proposed procedure facilitates the understanding of the performance requirements and evaluation of core materials used in composite ships and is expected to be utilized in developing core materials for marine structures.

• Journal of the Korea Institute of Military Science and Technology
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• v.19 no.6
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• pp.690-697
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• 2016

EOIS(electro-optical imaging system) is the main target of the laser weapon. Specially, the image sensor will be vulnerable because EOIS focuses the incident laser beam onto the image sensor. Accordingly, the laser-induced damage of the image sensor needs to be identified for the counter-measure against the laser attack. In this study, the laser-induced damage of the CCD image sensor irradiated by the CW(continuous wave) NIR(near infrared) laser was experimentally investigated and mechanisms of those damage occurrences were analyzed. In the experiment, the near infrared CW fiber laser was used as a laser source. As the fluence, which is the product of the irradiance and the irradiation time, increased, the permanent damages such as discoloration and breakdown appeared sequentially. The discoloration occurred when the color filter was damaged and then the breakdown occurred when the photodiode and substrate were damaged. From the experimental results, LIDTs(laser-induced damage thresholds) of damages were roughly determined.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.6
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• pp.7-13
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• 2015

The production processes were reviewed through the injection analysis of the shift lever as a core component of an auto lever installed in the automatic transmission of cars. The injection analysis was carried out for the shift lever and rod among the components in a shift lever module. The shift lever and rod are designed for injection molding with the insertion of a tube, a pin cable plate, and a steel rod for securing the strength of the product. The charging time, failure of injection molding, weld line, air trap, and deformation were reviewed according to this insert. Analyses on various gate positions were carried out for reviewing the cultivation and deformation of fiber around major components, such as the generation section of manipulation feeling and assembly section, so that optimal gate conditions might be reviewed and reflected in the mold design. Finally, we plan to compare the analysis results with the production of trial products.

• Journal of Biosystems Engineering
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• v.40 no.4
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• pp.394-408
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• 2015

Spectroscopy is an emerging technology for the quality assessment of pharmaceutical samples, from tablet manufacturing to final quality assurance. The traditional methods for the quality management of pharmaceutical tablets are time consuming and destructive, while spectroscopic techniques allow rapid analysis in a non-destructive manner. The advantage of spectroscopy is that it collects both spatial and spectral information (called hyperspectral imaging), which is useful for the chemical imaging of pharmaceutical samples. These chemical images provide both qualitative and quantitative information on tablet samples. In the pharmaceutics, spectroscopic techniques are used for a variety of applications, such as analysis of the homogeneity of powder samples as well as determination of particle size, product composition, and the concentration, uniformity, and distribution of the active pharmaceutical ingredient in solid tablets. This review paper presents an introduction to the applications of various spectroscopic techniques such as hyperspectroscopy and vibrational spectroscopies (Raman spectroscopy, FT-NIR, and IR spectroscopy) for the quality and safety assessment of pharmaceutical solid dosage forms. In addition, various chemometric techniques that are highly essential for analyzing the spectroscopic data of pharmaceutical samples are also reviewed.

• Textile Coloration and Finishing
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• v.30 no.2
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• pp.141-149
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• 2018

This study aimed to investigate the efficacy of eco-friendly leather dyeing by utilizing food wastes. Natural dyeing of eel skin was attempted using onion peels which have been used commonly for natural dyeing of textile fabrics. Eel skin is a by-product from fishery processing and is used mainly for making leather products. The colorant was extracted from onion peels in boiling water, concentrated, and freeze-dried. Dyeing of eel skin was carried out to study the effects of dyeing conditions, mordant type and mordanting method on dye uptake, color change, drape stiffness and colorfastness. The optimum dyeing conditions were $60^{\circ}C$ of dyeing temperature, 60min of dyeing time at 1:100($H_2O$ 90%: ethanol 10%) of bath ratio. The onion peels produced yellowish color on eel skin. The pre-mordanting was effective than the post-mordanting. As a result of the drape stiffness measurement, the Fe-mordanted sample was somewhat stiffer comparing to other mordanted samples. The light fastness of the non-mordant dye was excellent in 3-4 grade. Drycleaning fastness and rubbing fastness showed excellent results, but fastness was not significantly improved by mordanting.

• Journal of Nutrition and Health
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• v.40 no.6
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• pp.558-565
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• 2007

On the basis of the increasing interest for the selection of beverages, this study aimed to evaluate the contents of nutrients and health ${\cdot}$ functional elements in the beverages. Total 161 beverages that bear nutrition lable (NL) as nutrition table and health ${\cdot}$ functional elements information were collected and classified to 8 groups. The evaluated nutrients that are obligatory for NL in Korea were total calorie, carbohydrate, protein, fat, and sodium. Presented values showed that milk & yogurt and soy milk are the most wholesome beverages while the total caloric contents also were higher among 8 groups. Sodium contents in soy milk were higher than any other groups. The caloric contents of other beverage groups come mainly from carbohydrate presumably simple sugar. The caloric content of sports drinks is the lowest but the sodium content is variable among products showing the range of 0 - 100 mg/100 ml. Nonobligatory nutrients for NL frequently expressed are Ca, Fe, vitamin C, folate, and dietary fiber. Their content per serving size does not exceed the tolerable upper intake level, however, habitual multiple intakes of certain product require attention for the prevention of overintakes. Many health ${\cdot}$ functional elements as catechin, carnitine, polyphenol, and nucleic acids etc were listed in NL without presenting the content and their functions appear to be exaggerated compared to the known scientific evidence.

• KSBB Journal
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• v.32 no.3
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• pp.174-178
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• 2017

Fungal mycelium-based composite materials (FMBC) are a new biomaterial to replace the existing composite materials. To compete with lightweight, high-performance composite materials represented by fiber-reinforced plastic (FRP), various physical and chemical properties and functionality must be secured. Especially, the composite materials made by using mycelium of mushroom is called mushroom plastic. Currently, Ecovative, Grado Zero Espace and MycoWorks in USA and Europe are launching new products. Products utilizing FMBC can be launched in the market for construction materials, automobile interior materials and artificial leather substitutes. In spite of this high possibility, mass production using FMBC has not yet been reported. This review introduces the FMBC, a material that can replace existing plastics, inorganic building materials and animal skins in an environmentally and economically viable way, and looks at the possibility of future biomaterials by summarizing recent research contents.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.6
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• pp.92-98
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• 1998

The transform limited optical short pulses are generated by compression of pulses from a gain switched distributed feedback laser at 5 GHz repetition rate. The gain-switched pulses have the minimum pulse width of 27 psec with the spectral width of 1.1 nm. Thus the output pulses have a large amount of linear chirp and nonlinear chirp. We suppress the nonlinear chirp by passing the pulses through the optical band pass filter with 3 dB band width of 0.55 nm which is narrower than spectral width of the input pulses and generate 7.1 psec pulses by compressing the output with the dispersion compensating fiber. The pulses have time-bandwidth product of 0.49 which is close to the transform limited gaussian pulse. These pulses can be utilized as optical sources in 40 Gbit/s time division multiplexed optical transmission system.

• Journal of the Korean Society of Costume
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• v.59 no.10
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• pp.111-123
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• 2009

This study investigated the multifaced country image. The casual relationships among the multifaced country image, attitudes toward a country, and purchase emotion and purchase intention of fashion products with Korean images were also investigated. To conduct a quantitative analysis, we collected data from 296 Korean female consumers. SPSS 12.0 and AMOS 5.0 packages were used for statistical analysis. The results of this study as follows. To identify components of country image of Korea, exploratory and confirmatory factor analyses were conducted. This procedure produced five components such as culture, technique/product, ethical values, nationality, and space. Structural equational model was used to analyze the relationships among the country image, attitudes toward a country, purchase emotion, and purchase intention of fashion products with Korean image. The proposed model was verified.

• Korean Journal of Pharmacognosy
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• v.12 no.4
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• pp.185-189
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• 1981

The quality inspection was made on commercial Korean ginseng extract (Company A, B, C, D, E, F, G and H), particularly on samples available in Seoul market area. The results were as follews: 1) Among the ginseng extract products out of eight different manufactures, the moisture content of D company's product showed 46.5%, and other companys' met with the moisture standard for ginseng extracts. And protein, fat, ash, fiber and total sugar were about $9.87{\sim}21.07%,\;0.46{\sim}1.62%,\;6.55{\sim}7.88%,\;0{\sim}0.15%\;and\;58.58{\sim}76.74%$, respectively. And residue of D and F company products showed 3.25% and 3.61% which exceed the standard, and other company products met with residue test specifications. 2) The contents of ginseng saponins were 16.16% and 13.12%, respectively, for the C and H company products. However, other company's showed below 9%. By fractional distribution of ginseng saponins, it is supposed to be white ginseng and lateral ginseng that were mostly used as raw materials for ginseng extract manufacturing.