• Journal of the Society of Cosmetic Scientists of Korea
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• v.49 no.2
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• pp.117-125
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• 2023

In this study, the anti-inflammatory and anti-oxidative activities were compared for the extracts of non-fermented Ligustrum japonicum fruits (LJF) and fermented counterparts. U se of Latilactobacillus curvatus (L. curvatus) and Weissella minor (W. minor), isolated from the Jeju Chromis notata, as fermented strains led to the extracts of LJF-LC and LJF-WM in this experiment. The yield of each fermented extract (LJF-LC and LJF-WM) was 40.5 ~ 46.0%, higher than 29.5% of non-fermented extract (LJF). As a result of an activity experiment using RAW 264.7 macrophages stimulated by lipopolysaccaride (LPS), it was confirmed that LJF-WM, a fermented extract, has an excellent effect of inhibiting NO production in a concentration-dependent manner without cytotoxicity. Upon the screening of DPPH and ABTS⁺ radical scavenging activities, the fermented LJF-LC and LJF-WM showed comparable to the non-fermented LJF. In the study of cell protection effect using HaCaT keratinocytes damaged by hydrogen peroxide (H₂O₂), the fermented LJF-WM indicated protective effect against oxidative stress. In addition, quantitative analysis of a major constituent salidroside by HPLC indicated about 15.6 mg/g for the LJF-LC and 13.9 mg/g for the LJF-WM, which were higher than that of non-fermented LJF (12.0 mg/g). Based on these results, it was suggested that the fermented extract from L. japonicum fruits could be used as a natural cosmetics material with anti-inflammatory and anti-oxidative effects.

• Journal of Practical Engineering Education
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• v.15 no.1
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• pp.1-11
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• 2023

The purpose of this study is to develop and validate a tool that measures the satisfaction of virtual training learners' use of virtual training content. To this end, 491 copies of the basic questions derived from the satisfaction questions used by the K University Online Lifelong Education Center were used for the final analysis by conducting an online survey of learners who accessed STEP, the K University Online Lifelong Education Center portal. The 491 copies of data finally used were analyzed by methods such as basic question analysis, exploratory factor analysis, reliability analysis, and confirmatory factor analysis. First, in the basic question analysis, there were no questions that exceeded the acceptance criteria of an average of 4 points or more, skewness ±2, and kurtosis ±4. Second, the correlation coefficient for each sub-factor of virtual training content satisfaction derived after exploratory factor analysis was good as r=.682 to .822 (p<.01). The reliability coefficient for each sub-factor is content .849, content utilization .922, System and Operations Support .841, Intention to Continue Utilization .920, the overall reliability is. It was very high at .956 Fifth, as a result of confirmatory factor analysis, the compositional conceptual diagram is. It was .842 to .926, higher than the recommended standard of .7, and the average variance extraction degree. It appears to be .640 to .796, higher than the recommended standard of .5, which can be seen as representative of each constituent concept. As a result of verifying the validity of virtual training learners' content satisfaction recruitment, four factor models were derived: content substance, content utilization, system and operation support, and intention to continue use. This study is meaningful in that it empirically developed a tool to measure content satisfaction of virtual training learners and provided a reference frame and criteria.

• Resources Recycling
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• v.32 no.6
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• pp.54-66
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• 2023

Titanium's importance as a mineral resource is increasing, but the Korean industry depends on imports. Ilmenite is the principal titanium ore. However, research and development from raw materials have not been investigated yet in detail. Hence, measures to secure a stable titanium supply chain are urgently needed. Accordingly, through beneficiation technology, we evaluated the possibility of technological application for the efficient recovery of valuable minerals. As a result of the experiments, we confirmed that mineral particles existed as fine particles due to weathering, making recovery through classification difficult. Consequently, applying beneficiation technologies, i.e., specific gravity separation, magnetic separation, and flotation, makes it possible to recover valuable minerals such as hematite and rutile. However, there are limitations in increasing the quality and yield of TiO₂ due to the mineralogical characteristic of the hematite and rutile contained in titanium ore. Hametite is combined with rutile even at fine particles. Therefore, it is essential to develop mineral processing routes, to recover iron, vanadium, and rare earth elements as resources. On that account, we used grinding technology that improves group separation between constituent minerals and magnetic separation technology that utilizes the difference in magnetic sensitivity between fine mineral particles. The development of beneficiation technology that can secure the economic feasibility of valuable materials after reforming iron oxide and titanium oxide components is necessary.

• Korean Journal of Mineralogy and Petrology
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• v.36 no.4
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• pp.345-353
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• 2023

This study aimed to investigate the differences in the commercial powder products of the Yeongdong illite based on sales specifications, specifically examining the mineralogical composition, particle size, and chemical composition according to mesh size. The goal was to understand the characteristics of illite powder products and utilize them as a mineralogical database for exploring various applications. Commercial illite powder samples obtained from two mines were subjected to various experiments, including X-ray diffraction (XRD) analysis, laser diffraction particle size analysis, and scanning electron microscopy analysis, X-ray fluorescence analysis. The XRD analysis revealed that the illite powder products from the two mines mainly consisted of illite/muscovite, quartz, and feldspar, indicating similar constituent minerals matching with those of ores for each mine. Laser diffraction particle size analysis indicated the difference in particle size distribution depending on the product specifications, with particle size uniformity tending to increase with increasing mesh sizes. Scanning electron microscopy analysis showed variations in particle shape and size based on specifications. The size of illite particles did not vary significantly with product specifications, with noticeable changes observed mainly in the particle sizes of quartz and feldspar. Furthermore, although there were some differences in chemical composition among the samples from different mines, no significant variations were observed according to specifications. Based on these results, when considering the application of commercial illite powder, it is essential to carefully select it with the consideration of its specifications to account for characteristic variations. The findings of this study present support the great potential of various application fields of commercial illite powder, contributing to industrial utilization and the development of new technologies.

• Conservation Science in Museum
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• v.30
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• pp.89-100
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• 2023

Museum collections are comprised of a variety of materials, and different scientific examinations are being conducted according to the types and production properties of the materials, but insufficient research has been carried out on ultra-small artifacts. To identify the material characteristics of the white ultra-small materials excavated from Geumnyeongchong tomb, this study carried out a wide range of non-destructive analyses (specific gravity, microscopy, nano-computed tomography (Nano-CT), scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), X-ray diffraction (XRD), and Raman spectroscopy) and compared the said artifacts with the Goryeo-era burial accessories examined in prior research. Non-destructive analysis confirmed the presence of aragonite, which mainly consists of calcium carbonate (CaCO₃) as the constituent mineral, and identified the material used for the ornaments as the gemstone pearl based on its growth lines. This study concludes that pearls began to be used in the ancient Korean Peninsula in the 6^th century. It is expected that scientific examinations of the white ultra-small artifacts will yield information about the social culture of the time.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.14 no.3
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• pp.171-180
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• 2009

Based on the constituent analysis of sediments near Dok Island, the origin and sedimentary facies were Investigated. The sediments are mainly from originated from volcanic and volcaniclastic rock fragments derived from Dok Island and carbonate sediments formed by a variety of shallow-dwelling organisms that secreted calcareous skeletons. Carbonate producers include mollusks (bivalves and gastropods), encrusting & branching bryozoans, encrusting & segmented red algae, worm tubes, barnacles, diatoms, sponge spicules and echinoderm fragments. The distribution and relative amount of these constituents are basically dependent upon water depth and grain size even though local variations can be observed within the same depth interval. Five sedimentary facies can be divided: nearshore facies (<20 m), neritic facies ($20{\sim}100m$), upper transitional facies ($100{\sim}200m$), lower transitional facies ($200{\sim}700m$), and hemipelagic facies (>700 m). The sediments that were sampled below the water depth of 2,000 m still contain a significant amount of carbonates (ca. $10{\sim}20%$), implying that the carbonate compensation depth in the East Sea may well exceed this water depth.

• The Journal of Fisheries Business Administration
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• v.55 no.1
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• pp.55-76
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• 2024

The purpose of this study is to elucidate the impact of authenticity on experience value and subjective well-being among visitors who have participated in direct experiential activities in experiential fishing villages. The research method used literature research methods and empirical research methods using questionnaires, and this questionnaire was composed by determining three major variables and seven constituent factors for each variable through factor analysis and conducting prior research and preliminary surveys. The survey was conducted from February 5, 2023 to April 5, 2023 among experimental fishing villages with excellent ratings for scenery (environment), service, experience, accommodation, and food, and four villages that can experience tidal flats and manage customers online. The survey was conducted from February 5, 2023 to April 5, 2023, among experimental fishing villages with excellent ratings for scenery (environment), service, experience, accommodation, and food, and four villages that can experience tidal flats and manage customers online. The results of this study are as follows. First, the factors of authenticity in experiential fishing villages include three sub-factors: objective authenticity, constructive authenticity, and existential authenticity. The factors of experience value include two sub-factors: emotional values and functional values. Subjective well-being is derived from positive emotion and life satisfaction. Second, upon examining the importance of authenticity in experiential fishing villages, it was found that existential authenticity and objective authenticity, in that order, have a significant impact on emotional values. However, constructive authenticity did not have a significant impact on emotional values. Third, in terms of functional values, constructive authenticity, existential authenticity, and objective authenticity, in that order, had a significant impact. Fourth, experience value, in the order of emotional values and functional values, had a significant impact on positive emotion and life satisfaction of subjective well-being. Therefore, it was confirmed that the authenticity of experiential fishing villages is important as a strategy to enhance experience value and subjective well-being. Especially, considering that the majority of visitors to experiential fishing villages are family-centered (86.5%), applying marketing management strategies to develop programs that enhance existential authenticity and improve emotional values could elevate the subjective well-being of experiential visitors.

• Journal of the Korean Wood Science and Technology
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• v.52 no.3
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• pp.221-233
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• 2024

Lignin, a prominent constituent of woody biomass, is abundant in nature, cost-effective, and contains various functional groups, including hydroxyl groups. Owing to these characteristics, they have the potential to replace petroleum-based polyols in the polyurethane industry, offering a solution to environmental problems linked to resource depletion and CO₂ emissions. However, the structural complexity and low reactivity of lignin present challenges for its direct application in polyurethane materials. In this study, Kraft lignin (KL), a representative technical lignin, was fractionated with ethanol, an eco-friendly solvent, and mixed with conventional polyols in varying proportions to produce polyurethane films. The results of ethanol fractionation showed that the polydispersity of ethanol-soluble lignin (ESL) decreased from 3.71 to 2.72 and the hydroxyl content of ESL increased from 4.20 mmol/g to 5.49 mmol/g. Consequently, the polyurethane prepared by adding ESL was superior to the KL-based film, exhibiting improved miscibility with petrochemical-based polyols and reactivity with isocyanate groups. Consequently, the films using ESL as the polyol exhibited reduced shrinkage and a more uniform structure. Optical microscope and scanning electron microscope observations confirmed that lignin aggregation was lower in polyurethane with ESL than in that with KL. When the hydrophobicity of the samples was measured using the water contact angle, the addition of ESL resulted in higher hydrophobicity. In addition, as the amount of ESL added increased, an increase of 7.4% in the residual char was observed, and a 4.04% increase in Tmax the thermal stability of the produced polyurethane was effectively improved.

• Advances in nano research
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• v.16 no.6
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• pp.565-577
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• 2024

Vibration investigation of fluid-filled functionally graded cylindrical shells with ring supports is studied here. Shell motion equations are framed first order shell theory due to Sander. These equations are partial differential equations which are usually solved by approximate technique. Robust and efficient techniques are favored to get precise results. Employment of the Rayleigh-Ritz procedure gives birth to the shell frequency equation. Use of acoustic wave equation is done to incorporate the sound pressure produced in a fluid. Hankel's functions of second kind designate the fluid influence. Mathematically the integral form of the Langrange energy functional is converted into a set of three partial differential equations. A cylindrical shell is immersed in a fluid which is a non-viscous one. These shells are stiffened by rings in the tangential direction. For isotropic materials, the physical properties are same everywhere where the laminated and functionally graded materials, they vary from point to point. Here the shell material has been taken as functionally graded material. After these, ring supports are located at various positions along the axial direction round the shell circumferential direction. The influence of the ring supports is investigated at various positions. Effect of ring supports with empty and fluid-filled shell is presented using the Rayleigh - Ritz method with simply supported condition. The frequency behavior is investigated with empty and fluid-filled cylindrical shell with ring supports versus circumferential wave number and axial wave number. Also the variations have been plotted against the locations of ring supports for length-to-radius and height-to-radius ratio. Moreover, frequency pattern is found for the various position of ring supports for empty and fluid-filled cylindrical shell. The frequency first increases and gain maximum value in the midway of the shell length and then lowers down. It is found that due to inducting the fluid term frequency result down than that of empty cylinder. It is also exhibited that the effect of frequencies is investigated by varying the surfaces with stainless steel and nickel as a constituent material. To generate the fundamental natural frequencies and for better accuracy and effectiveness, the computer software MATLAB is used.

• Sim-seong Yeon-gu
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• v.38 no.1
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• pp.45-111
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• 2023

This paper examines the apparition of the Virgin Mary revealed in Rue du Bac, Paris, France, in 1830, from a perspective of analytical psychology. To do so, it amplifies the archetypal motifs manifested in the images of the Virgin Mary of Rue du Bac by introducing the medieval alchemical picture titled "Glorification of the body portrayed as the coronation of the Virgin Mary" from Reusner's Pandora (1588). This image of the Virgin Mary is full of archetypal motifs that show the process and end result of individuation, which is the main idea of Jungian psychology. These symbols that depict the individuation process, both in Reusner's Pandora and in the Mary of Rue du Bac, are expressions of mythologems, constituent elements of the collective unconscious. Jung noted that these mythologems are the ultimate base and matrix of all religions. Through examining the archetypal motifs, which appear in the Mary of Rue du Bac, the apparition of the Mary turns out to be the revelation of the archetypal image of the Self in a space-time continuum, which is constellated in the collective unconscious. That is, an archetypal figure revealed itself to a witness' ego-consciousness to whom a space-time continuum functions as a cognitive category. The Mary of Rue du Bac represents the union of the opposites of divinity and humanity, which lacks in the symbolism of the Cross in Christianity. In this regard, she is an image of the new savior, who opens the new aeon of the Aquarius. The revealed image of Mary shows that divinity originates from the inner realm of the human psyche, that corporeal human beings are the matrix in which the divine incarnates, and that human being is the subject of psychological redemption. The image of Mary awakens us to the value of divinity in the human psyche in the times when the spiritual values Christianity has retained declines drastically.