• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.4
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• pp.388-395
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• 2016

This paper explores the photocatalytic sensitivity of cement mortar incorporated with recycled $TiO_2$ from waste water sludge. Basically, $TiO_2$ cluster sank down slowly to the bottom of cement mortar specimen before setting and hardening process. This leads the mismatch of $TiO_2$ concentration on the top and the bottom faces of a specimen. This poorly dispersed $TiO_2$-cement mortar naturally exhibits poor NOx removal efficiency especially on the top of cementitious structure. In architectural engineering application such as building or housing structures, one can simply filp over from the bottom so that more $TiO_2$ concentrated surface can be placed outward into the air. However, in highway pavement case, this could not be applicable due to in-situ installation of concrete pavement. Hence, the dispersion of $TiO_2$ cluster inside the cementitous material is getting important issue onto road construction application. To elaborate this issue, according to our results, silica fume, high-ranged water reducer, viscosity agent, blast furnace slag were not enhanced much of dispersion characteristics of $TiO_2$ cluster. The combination of foaming agent and accelerator of hardening with viscosity agent and small grain size of fine aggregate may help the dispersion of $TiO_2$ inside cementitious materials. Even though the enhanced dispersion were applied to the specimen, NOx removal efficiency doest not change much for the top surface of the specimen. This concurrently affected by the presence of tiny air voids and the dispersion of $TiO_2$ in that these voids could easily adsorbed NOx gas with the aid of large surface area.

• Archives of design research
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• v.19 no.2 s.64
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• pp.99-108
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• 2006

Based on the results from the already published 'A study on factors that make busy of street space' and 'A study on street the image evaluation of streetscape', this study is an attempt to explore factors, other than the structural factors, that compose the street space and affect the image of street to be more lively. First of all, this study was mainly concentrated on the structure of street space that fits the theory of the previous two theses, stating that the structural ratio ($D/H=0.5{\sim}2$) gives the street an interesting image. The next study subject was the street space that exhibits the amenity and busy of image according to the space structure ratio. I defined that exhibiting amenity and busy means the activation of the street space, and I attempted to extract the activation factors from the component elements. The street space that shows amenity and busy image after the activation was named as 'lively street space' in this study. Furthermore, I selected 20 street spaces, after classifying the whole, according to nations and local characteristics as the previous theses had done and looked for the 'lively street space', whose structural ratio was not in the range of $D/H=0.5{\sim}2$ and the factors that contributed to the Image. As the result, I founded that in case of the business areas with the ratio of $D/H=0.5{\sim}2$, street activation factors were hydroponic facilities, sidewalks, and wayside buildings and In case of the commercial areas, the factors were sidewalk, wayside buildings, hydroponic facilities, and illumination facilities. Especially, 5 commercial areas in Korea and 1 business areas in Japan did not have the structural ratio of $D/H=0.5{\sim}2$, but still exhibited lively image as streets. This was because aside from the structural element, other street activation factors such as facilities also had major contribution in these streets. In other words, in commercial areas in Korea have wayside buildings, sidewalks, and hydroponic facilities as activating factors, whereas in street spaces in business areas in Japan, hydroponic facilities, wayside buildings, and sidewalk factors are influential to the activation of street spaces.

• Applied Biological Chemistry
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• v.49 no.3
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• pp.186-191
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• 2006

In the present study, an attempt has been made to produce hybrid yeast strains of different useful and dominant characteristics. The hybrid yeast strains were produced by electrofusion and their genetic analysis were performed by RAPD-PCR (random amplified polymorphic DNA-polymerase chain reaction). The protoplast of Saccharomyces cerevisiae KCTC 7904 and Zygosaccharomyces rouxii KCTC 7966 were obtained above 92% when treated with lyticase at $30^{\circ}C$ for $60{\sim}90$ min after the pretreatment of $1{\sim}2%$ 2-mercaptoethanol at $30^{\circ}C$ for $15{\sim}20$ min. The fusant was produced from paired protoplast stage under the electric pulse at high frequency conditions (1.5 MHz/50 pV, 615 $V/256\;{\mu}sec$) within glass-platinum made electrofusion chamber. Changes in RAPD patterns in mother cells and hybrid cells proved that the fusant contains two types of yeast gene originated from its parent. Furthermore, fermentation characters exhibits by the fusant cell confirmed its genetic changes. These results suggest that genetically stable hybrid yeast strains of economic importance can be produced by electrofusion technique and these electrofused yeast cells have an enormous impact in biotechnology and biomedicine.

• Journal of Service Research and Studies
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• v.13 no.2
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• pp.181-203
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• 2023

YouTube exhibits a hybrid personality, incorporating traits of both over-the-top (OTT) and personal broadcasting platforms. However, limited research has investigated these hybrid characteristics, particularly in the context of paid YouTube channel memberships. Therefore, building upon consumption value theory and prior literature, this study examines the influence of consumption value factors associated with paid YouTube channel memberships on usage satisfaction and continuance intention. Specifically, the study identifies four perceived consumption value factors (functional, social, emotional, and epistemic values) within the paid YouTube channel membership context and assesses their impact on usage satisfaction and continuance intention. Additionally, the study explores the moderating role of conditional value (the experience of watching live streams on paid YouTube channels) in these relationships. Data was collected via an online survey from Korean adults who subscribed to multiple paid YouTube channel memberships, resulting in 274 responses. The proposed hypotheses were tested using structural equation modeling (SEM). The SEM results indicate that all four consumption value factors significantly influence usage satisfaction, with usage satisfaction in turn positively affecting continuance intention. Furthermore, the study reveals that conditional value moderates the relationships between functional/emotional values and usage satisfaction, as well as between usage satisfaction and continuance intention. This study is the first to focus on YouTube channel paid memberships, which encompass characteristics from both OTT and personal broadcasting platforms. It is anticipated that this research will offer insights to personal broadcasters and stakeholders regarding the motivational factors that impact user satisfaction and encourage subscriptions to channel memberships.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.34 no.1
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• pp.40-52
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• 2016

Buyongjeong, a pavilion in the Rear Garden of Changdeok Palace, was appointed as Treasure No. 1763 on March 2, 2012, by the South Korea government since it shows significant symmetry and proportion on its unique planar shape, spatial configuration, building decoration, and so forth. However, the designation of Treasure selection was mainly evaluated by concrete science, in that the selection has not clearly articulated how and why Buoungjeong was constructed as a present unique form. Therefore, this study aims to clarify the identity of Buyongjeong at the time of construction by considering its historical, ideological, philosophical background and building intention. Summary are as follows: First, Construction backgrounds and characters of Buyongjeong: Right after the enthronement, King Jeongjo had founded Kyujanggak(奎章閣), and sponsored civil ministers who were elected by the national examination, as a part of political reform. In addition, he established his own political system by respecting "Kaksin(閣臣)", Kyujanggak's officials as much as "Kain(家人)", internal family members. King Jeongjo's aggressive political reform finally enabled King's lieges to visit King's Rear Garden. In the reign of King Jeongjo's 16th year(1792), Naekaksangjohoe(內閣賞釣會) based on "Kaksin" was officially launched and the Rear Garden visitation became a regular meeting. The Rear Garden visitation consisted of "Sanghwajoeoyeon(賞花釣魚宴)" - enjoying flowers and fishing, and activities of "Nanjeongsugye". Afterward, it eventually became a huge national event since high rank government officials participated the event. King Jeongjo shared the cultural activities with government officials together to Buyongjeong as a place to fulfill his royal politics. Second, The geographical location and spatial characteristics of Buyongjeong: On the enthronement of King Jeongjo(1776), he renovated Taeksujae. Above all, aligning and linking Gaeyuwa - Taeksujae - a cicular island - Eosumun - Kyujangkak along with the construction axis is an evidence for King Jeongjo to determine how the current Kyujangkak zone was prepared and designed to fulfill King Jeonjo's political ideals. In 17th year(1793) of the reign of King Jeongjo, Taeksujae, originally a square shaped pavilion, was modified and expanded with ranks to provide a place to get along with the King and officials. The northern part of Buyongjeong, placed on pond, was designed for the King's place and constructed one rank higher than others. Discernment on windows and doors were made with "Ajasal" - a special pattern for the King. The western and eastern parts were for government officials. The center part was prepared for a place where government officials were granted an audience with the King, who was located in the nortern part of Buyongjeong. Government officials from the western and eastern parts of Buyongjeong, could enter the central part of the Buyongjeong from the southern part by detouring the corner of Buyongjeong. After all, Buyongjeong is a specially designed garden building, which was constructed to be a royal palace utilizing its minimal space. Third, Cultural Values of Buyongjeong: The Buyongjeong area exhibits a trait that it had been continuously developed and it had reflected complex King's private garden cultures from King Sejo, Injo, Hyunjong, Sukjong, Jeongjo and so forth. In particular, King Jeongjo had succeded physical, social and imaginary environments established by former kings and invited their government officials for his royal politics. As a central place for his royal politics, King Jeongjo completed Buyongjeong. Therefore, the value of Buyongjeong, as a garden building reflecting permanency of the Joseon Dynasty, can be highly evaluated. In addition, as it reflects Confucianism in the pavilion - represented by distinguishing hierarchical ranks, it is a unique example to exhibit its distinctiveness in a royal garden.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.3
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• pp.225-237
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• 1990

Various chemical constituents were measured from April to August 1988 at the down-ward 20 stations of Keum River, which is located in the Midwest of Korea, to understand the characteristics of water quality with respect to spatio-temporal variations of each constituent. The 24-hrs continuous measurements with 2-hrs interval were made simultaneously at station 2 near the estuary weir and station 9(Ganggyeong) of 35 km upstream from the weir in April. By the results observed for one day in April at station 2, salinity has a range of $7.88\~22.14\%_{\circ}$ and its temporal variability is identical to the pattern of tidal cycle in the neigh-bouring Kunsan Harbor. However, turbidity shows relatively high values only at an interval of 4~5 hours after the lowest salinity time, though hourly fluctuation of pH is very small. Silicate and dissolved inorganic nitrogen have inversively linear correlationships with salinity, implying the concentration of the two nutrients strongly regulated by estuarine mixing of sea and river waters. In contrast, phosphate sustains roughly a constant level over a wide salinity range and distinctly lower values than those corresponding to nitrate in the oceans. Such distributions of phosphate have been observed in some estuaries, and interpreted as driven by removal of dissolved phosphate into bottom sediments and the bufforing of phosphate by particulate matter. COD values at station 2 are relatively high in day-time(particularly afternoon) and in high-salinity periods. At station 9, saltwater intrusion was never found but water level changed to the extent of 2.5 m for one day. Although each parameter at this station exhibits very slight variations in their abundance for 24 hours compared with station 2, the contents of COD, silicate and ammonia are significantly higher than at station 2. Concentration of suspended matter is relatively high in the brackish water region up to $\~20$ km above the river mouth, probably due to strong tidal stirring of the bottom de-posits. Also, relatively high pH, COD and $O_2$ saturation at the upward stations of $40\~50$ km from the weir are presumably attributable to active photosynthesis of plants in the region. In general, COD and nutrients except phosphate are higher values at the upper stations than in the estuary zone, and show the highest abundances in July nearly at all stations. Finally, in the estuarine region tidal mixing of sea-river waters seems to be an important factor controlling the distributions of turbidity, COD, silicate and nitrate as well as salinity. However, water quality in the upward fresh-water zone is remarkably variable according to months or seasons.

• Korean Journal of Heritage: History & Science
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• v.57 no.1
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• pp.54-79
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• 2024

The purpose of this research is to fill the vacuum created by the tendency of bias towards China among the curators of Korean museums who plan exhibitions focusing on Balhae, and to share with researchers in the countries concerned various supplementary research materials that could deepen their understanding of the history of Balhae. These materials are based on analyses of the details of exhibitions about Balhae held in a particular Russian museum and the characteristics of and changes in the museum's operational policy. Thus, this research focuses mainly on the permanent and special exhibitions held by the Far East History Museum and Reserve, whose collection represents the archaeological achievements of Russia regarding the history of Balhae. The first part of the research focuses on the layout of the exhibitions presented by the museum and the museum's operational policy. It reveals that the museum's permanent exhibitions follow a diachronic arrangement of the local history, while the first and second special exhibitions featured exhibits that were selected from the collections of the Russian Academy of Sciences and arranged according to specific themes. It also examines the museum's policy for operating the exhibitions, focusing on the operational rules, the human resources deployed to run them, and the related educational and PR programs. The second part of the research examines such issues as local politics, economy, education and culture related to the exhibitions on Balhae's history, and connects them to the background and development of the exhibitions. This study reveals that the permanent exhibitions were intended to promote historical awareness of the local area by museum visitors, particularly those who visited the exhibitions while the city was hosting important events such as international summits. It also reveals that the museum's first special exhibition led to the promotion of Korea-Russia cooperation on exchanges in the fields of culture and tourism, whereas the second special exhibition involved no PR efforts or related events, which was probably due to the changes that have occurred in the relationship between Russia and its neighboring countries since then. The final part of the study focuses on the characteristic features of the exhibition narratives, and compares school textbooks on local history and history books for general readers with the contents of the exhibitions. The analysis of the narratives based on the development of time shows that the history of the Mohe (or Malgal) tribes has been combined with that of Balhae, while they are treated separately in school textbooks. As regards political history, the narrative was largely focused on officials in Balhae's central government rather than on Mohe warriors in the border areas. The maps of Balhae presented in the exhibitions highlight the importance of accumulating empirical data. As for the exhibition of material cultures, this study suggests that the museums should obtain more archaeological floral and faunal remains related with agriculture and hunting. It also points out that the narrative on the theme of foreign relations deals with the archaeological relics of Unified Silla together with those of the Turkic tribes. As for the theme of philosophy and culture, the narrative focused on the state ceremonies and rituals of Goguryeo, a theme that has attracted little attention among Korean academic circles and which consequently requires further study. In conclusion, this study is meaningful in that it suggests a number of research topics regarding the development of exhibitions and exhibition narratives about the history of Balhae by a prestigious Russian museum that specializes in this subject.