• Korean Chemical Engineering Research
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• v.59 no.4
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• pp.542-547
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• 2021

Glass lined impellers are corrosion resistant to most chemicals, including strong acids, and also have a smooth, non-stick surface, easy to clean and free from impurities in the process. Glass lined home base impeller is a multi-purpose impeller designed to stir a wide viscosity range of liquids from low viscosity fluids to high viscosity fluids, among others, cell culture, yeast culture, and beer fermentation pots, especially used for air-water system breathable stirring. The glass lining for HB impellers, which are simple in structure and competitive in performance, is essential to have upper and lower division in order to make the joint area between the impeller and shaft as small as possible. The upper and lower division of the impeller hardly affects the mixing performance, but the aeration performance. In this study, in order to optimize the shape of the Glass Lining HB impeller, a study was conducted on the effect of the angle between the upper and lower impellers, the clearance between the impellers, and the number of baffles on the aeration power. The optimal shape and baffle plate conditions for the Glass lined HB impeller were derived through the study results that the angle and the clearance between the upper and lower impellers decreased the ration of the power consumption with aeration P_g and that without aeration P₀, P_g/P₀.

• (The) Research of the performance art and culture
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• no.35
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• pp.441-470
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• 2017

This paper deals with three issues related to influx and change of the Confucian Shrine Ritual Music. First, the musical instrument of the Akhakgwebeom-wooden frame-form used in the current Confucian Shrine Ritual Music is not a form that came in when the Daesung-Aak of the Song Dynasty was introduced in 1116, but it is a Yuan Dynasty form brought from the Ming Dynasty, in the 19th year of King Kongmin. In the Song Dynasty of the Goryeo Yejong era, when Daesung-Aak came in, there was not yet 'Baeso', a musical instrument of the Akhakgwebeom form, which first appeared in the Yuan Dynasty. A new musical instrument named 'Baeso' appears with the 'So' in the later period of King Gongmin, and it is very likely that this 'Baeso' is the musical instrument of the present Akhakgwebeom form. Second, although the form of the 'So' in the Joseon Dynasty recorded in the Akhakgwebeom was followed by the Chinese one, but the pitch and arrangement are the one of the pitch of '12 Yul and 4 Cheongseong' and the arrangement of the pitch from left to right. Third, in the 1930s, the whole form was the same as that of the Akhakgwebeom, but there existed two types, which several pipes stick together or pipes fall apart. But since then, as seen in the musical instrument located at Kyungpook National University Museum and in instruments currently used in Confucian Shrine Ritual Music, only musical instruments exist which pipes fall apart. It is unclear for what reason and to what extent the 'So' were so transformed, but it would be appropriate to re-establish the form of the 'So' in the musical and historical point of view.

• The Journal of the Korea Contents Association
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• v.22 no.6
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• pp.283-294
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• 2022

In this era of globalization, people's knowledge and cultural aesthetics are strongly influenced by the cultures of different countries, and diversified art forms have broken the traditional art framework, so how to stick to the essence of the country's traditional culture and make it inherited has became an important issue that cannot be ignored in the development of music today. Tan Dun, as one of the representative figures of Chinese contemporary music, has brought important inspirations to the development of Chinese music. With bold and free conceptions, innovative personality, unique Chinese tradition and international perspective. With a spirit of breaking down the barriers between tradition and modernity, East and West, and a concept of integrating multiple cultures into one, he has become a unique figure in the world of music. As researchers in composition, not only do we take on the responsibility of passing on Chinese culture, but we also need to explore the future development direction of Chinese music. Therefore, this paper takes Tan Dun's four traditional musical elements of organic music, Buddhist culture, witchcraft beliefs, folk songs and opera in his works and examines how Tan Dun perfectly blends traditional Chinese music culture with contemporary music language. And explore how the domestic traditional culture co-exists with modernity in today's diverse world.

• The Journal of the Korea Contents Association
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• v.22 no.2
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• pp.695-709
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• 2022

This study examined the mothers' stress level as it related to meal preparation and a change in food consumption during the Covid-19 pandemic. I asked mothers about the difficulties related to meal preparation, changes in food consumption, and their interest in food and health information using in-depth research methods. As a result, food delivery and online food consumption have markedly expanded as eating out has decreased. Mothers tried to serve fresh food at home because they perceived delivery food as unhealthy. They stick to it more vigorously with their younger children. As the result of analysis on determinants of food consumption, their interest in organic food is higher when mothers' ages are younger with higher income. However, mothers with a low level of education tend to be uninterested in it. Therefore, the ages of the children and mothers, household income, and education levels all had an effect on food consumption behaviors.

• Journal of People, Plants, and Environment
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• v.22 no.6
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• pp.593-600
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• 2019

We identified how plants affected by the human behavior of crushing plants respond and what kind of plants responded sensitively. We investigated Lactuca sativa "Gaesebadak", Syneilesis palmata and Peucedanum japonicum as plants that humans use for edible purposes, and Achyranthes japonica and Bidens bipinnata as wild plants that stick to people's clothes and disperse seed. Plants exposed to human breathing air were compared with those exposed to human breathing air after being crushed. Methyl jasmonate (MeJA), a chemical word, was measured using Syft/MS, which detects real-time VOC, and related genes were analyzed. The amount of MeJA of Syneilesis palmata and Peucedanum japonicum as edible plants was greater than that of non-edible plants that disperse seeds using humans. The amount of MeJA ranged from 0.20 ppb to 0.35 ppb when the control group were not exposed to human breathing air. On the other hand, MeJA decreased after increasing for the first hour in human breathing air. Also, MeJA affected by human breathing after crushing plants was higher than that affected by just human breathing air. Peucedanum japonicum showed the most distinctive difference between the treatment with human breathing after crushing plants and the treatment with just human breathing. In addition, the gene activity of JAR1 and JMT increased 3 hours after the treatment with human breathing after crushing plants. Therefore, in the treatment with human breathing after crushing plants, the concentration of MeJA and the activity of related genes showed the same tendency to increase. As a result, the plant that responded sensitively to human behavior was Peucedanum japonicum. Plants released MeJA as a chemical word in the treatment with human breathing air after crushing plants.

• Science of Emotion and Sensibility
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• v.26 no.1
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• pp.65-78
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• 2023

Aircraft are representative of human-machine systems. There is a delay between the human operation and the completion of the machine operation such as when the machine starts to operate and when the force is transmitted to the machine and completed. Time perception is an important component of timing tasks and is known to be affected by the anxiety associated with high arousal. This research verified the impact of weather, flight, and time conditions on the anxiety and time perception of in-service pilots in a virtual reality area. Weather conditions were divided into visual flight weather conditions and very low visibility conditions. Experiments 1 and 2 were performed with different flight and time conditions. In Experiment 1, time perception was measured by employing a button added to the control rod in the scenario of hovering and level flight with relatively little transformed in momentum and little delay. In Experiment 2, time perception was measured in the procedure of naturally taking off the helicopter by employing only the control stick in a takeoff scenario where there was a lot of transformation in momentum and a lot of delays. As a result of the experiment, it was reported that anxiety and heart rate increased in very low visibility conditions In particular, among all flight conditions in Experiments 1 and 2, it was reported that time was overestimated in the scenario of increased anxiety. This outcome can lead to overestimation of time under the impact of anxiety and failure of the timing task, which may lead to challenges in maneuvering and possibly lead to accidents.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.20 no.1
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• pp.23-38
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• 2009

The purpose of this study was to suggest the collection codes and simplification of call numbers for children's easy access to the children's materials. The classification schemes, author tables, expansion of classification schemes, collections codes, classification numbers used in domestic and foreign children's libraries were surveyed through questionnaires and interviewing with librarians. As a result, in foreign children's libraries, it was common practice to shelve children's materials separately into various collections and sub-collections, to mark the spine with collection code and the lead characters of the author's last name, and not to stick with their classification scheme when it comes to highly circulated children's materials such as fiction, picture book, biographies and so on. Also, in domestic children's libraries, it was found that a collection code was used a few and each call number was almost assigned by KDC number. Therefore, it was suggested that the types and codes of collection and sub-collection were divided as non-fiction, fiction, fiction/mystery, fiction/science fiction, picture book, cartoon, language, folks and fairy tales, biographies, legend, concept book, holiday, award, dinosaur, insect, DIY, transportation, tall book, pop-up, story book, board book, reference, magazine, series, new book, video, and audio and were easily expanded by combining age tables or fiction genre. Also, new simplifying methods of building call numbers with collection codes were suggested.

• Journal of Korea Entertainment Industry Association
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• v.13 no.8
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• pp.151-156
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• 2019

In recent years, the Korean realistic theme of the film momentum gradually rising. Realistic films do not stick to the business and market, and do not simply cater to the audience's needs for watching movies. They reflect social violence and cruel reality, allowing the audience to observe the structural contradictions in reality and think about the direction when watching movies. At the recent cannes film festival, "parasite" won the top prize palm in cannes by an overwhelming margin, with the highest score of 3.3 issues. Although this film is positioned as a thriller with comedy elements, it presents the opposite life images of Korean classes to the audience in a parasitic way, which not only expands the possibility and artistry of realistic film aesthetics, but also enhances the appreciation of the film and gives play to its own aesthetic value. Focusing on the technical and literary nature of the film, and having a high degree of attention to real life, it is an excellent work that tells about class opposition and thinking about reality. This paper considers and analyzes the content, form and creation method of parasite, and discusses the continuous exploration and attempt of realistic film to image language under the demand of market and system, evolving into new aesthetic expression.

• Journal of the Society of Naval Architects of Korea
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• v.60 no.5
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• pp.375-387
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• 2023

The subsea power cables are increasingly important for harvesting renewable energies as we develop offshore wind farms located at a long distance from shore. Particularly, the continuous flexural motion of inter-array dynamic power cable of floating offshore wind turbine causes tremendous fatigue damages on the cable. As the subsea power cable consists of the helical structures with various components unlike a mooring line and a steel pipe riser, the fatigue analysis of the cables should be performed using special procedures that consider stick/slip phenomenon. This phenomenon occurs between inner helically wound components when they are tensioned or compressed by environmental loads and the floater motions. In particular, Vortex-induced vibration (VIV) can be generated by currents and have significant impacts on the fatigue life of the cable. In this study, the procedure for VIV fatigue analysis of the dynamic power cable has been established. Additionally, the respective roles of programs employed and required inputs and outputs are explained in detail. Demonstrations of case studies are provided under severely sheared currents to investigate the influences on amplitude variations of dynamic power cables caused by the excitation of high mode numbers. Finally, sensitivity studies have been performed to compare dynamic cable design parameters, specifically, structural damping ratio, higher order harmonics, and lift coefficients tables. In the future, one of the fundamental assumptions to assess the VIV response will be examined in detail, namely a narrow-banded Gaussian process derived from the VIV amplitudes. Although this approach is consistent with current industry standards, the level of consistency and the potential errors between the Gaussian process and the fatigue damage generated from deterministic time-domain results are to be confirmed to verify VIV fatigue analysis procedure for slender marine structures.

• Journal of Environmental Health Sciences
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• v.50 no.1
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• pp.36-42
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• 2024

Background: The use of scented candles and incense sticks, both of which are household products that are burned for indoor deodorization and calming effects, is increasing. Fine dust has been designated as a group 1 carcinogen by the International Agency for Research on Cancer. Volatile organic compounds (VOCs) affect air pollution and can cause diseases. Objectives: This study aims to determine the effect on indoor air quality by measuring PM_2.5 and VOCs generated when burning scented candles and incense sticks. Methods: Scented candles and incense sticks were selected as household products to burn. As for the target sample, top-selling products (five types of scented candles, five types of incense sticks) were purchased online. The PM_2.5 concentration according to time was measured immediately next to the sample and three meters away from each other in an enclosed space using a real-time aerosol photometer. VOCs were collected as samples under the same conditions using Tenax tubes and were quantitatively analyzed by TD-GC/MS. Results: In the case of scented candles, the concentration of PM_2.5 did not increase during combustion and after being extinguished by placing a cover on the candle. For the incense sticks, the concentration of PM_2.5 averaged 1,901.27 ㎍/m³. After burning scented candles and incense sticks, some VOCs concentrations were increased such as ethyl acetate and BTEX (benzene, toluene, ethylbenzene, xylene). Conclusions: Therefore, when using scented candles, extinguishment by placing a cover on the candle can be expected to reduce PM_2.5. It is advisable to avoid using incense sticks because PM_2.5 concentration increases from the start of combustion.