• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.34 no.2
• /
• pp.73-77
• /
• 2024

The spinel-type oxide (Ni_x, Mn_y, Co_3-x-y)O₄ (NMC) is widely utilized as a material for temperature sensors with a negative temperature coefficient (NTC), finding applications across various industries including electric vehicle battery management systems. Typically, NMC is manufactured using solid-state reaction methods employing powders of Ni, Mn, and Co compounds, with the densification process through sintering recognized as a crucial factor determining the electrical properties of the temperature sensor material. In this study, NMC pellets were synthesized via solid-state reaction and their crystallographic and microstructural characteristics were investigated. Also, the activation energy for densification behavior during the sintering process was determined. According to the analysis results, the room temperature resistance of the NMC pellets was measured at 10.03 Kohm, with the sensitivity parameter, B-value, recorded at 3601.8 K, indicating their potential applicability as temperature sensors across various industrial fields. Furthermore, the activation energy for densification was found to be 273.3 ± 0.4 kJ/mol, providing valuable insights into the thermodynamic aspects of the sintering process of the NMC.

• Journal of Korea Water Resources Association
• /
• v.57 no.3
• /
• pp.195-207
• /
• 2024

This study selected major drought events that occurred in the Jeonnam region from 1991 to 2023, examining both meteorological and hydrological drought occurrence mechanisms. The daily drought index was calculated using rainfall and dam storage as input data, and the drought propagation characteristics from meteorological drought to hydrological drought were analyzed. The characteristics of the 2022-23 drought, which recently occurred in the Jeonnam region and caused serious damage, were evaluated. Compared to historical droughts, the duration of the hydrological drought for 2022-2023 lasted 334 days, the second longest after 2017-2018, the drought severity was evaluated as the most severe at -1.76. As a result of a linked analysis of SPI (StandQardized Precipitation Index), and SRSI (Standardized Reservoir Storage Index), it is possible to suggest a proactive utilization for SPI(6) to respond to hydrological drought. Furthermore, by confirming the similarity between SRSI and SPI(12) in long-term drought monitoring, the applicability of SPI(12) to hydrological drought monitoring in ungauged basins was also confirmed. Through this study, it was confirmed that the long-term dryness that occurs during the summer rainy season can transition into a serious level of hydrological drought. Therefore, for preemptive drought response, it is necessary to use real-time monitoring results of various drought indices and understand the propagation phenomenon from meteorological-agricultural-hydrological drought to secure a sufficient drought response period.

• Korean Journal of Heritage: History & Science
• /
• v.57 no.1
• /
• pp.126-144
• /
• 2024

The chrysanthemum vine pattern box from the Goryeo Dynasty expresses in great detail the representative features of Goryeo Dynasty lacquerware with mother-of-pearl, such as engraving patterns on the surface of fine mother-of-pearl, expressing vine stems using metal wires, and twisting metal wires to form the boundaries of each patterns. While the lacquerware with mother-of-pearl that remains today from the Goryeo Dynasty has the form of a sutra box and a box with lid, the chrysanthemum vine pattern box that is the subject of this study is in the shape of a box with a separate lid and body, making it difficult to estimate the purpose of production or the stored contents. In this study, we attempted to confirm the formative characteristics of the chrysanthemum vine pattern box in order to confirm its original form, and to investigate its structure and production technique through X-ray transmission. In addition, we attempted to identify the use and production purpose of the box by classifying and comparing the previously known lacquerware with mother-ofpearl from the Goryeo Dynasty by type. As a result of the investigation, fabric was confirmed the bottom of body and inner box through X-ray images. Through this, it was confirmed that the 'Mogsimjeopichilgi'(wooden core grabbing fabric technique) of wrapping the object with fabric was used. And through wood grain, it was possible to confirm the wooden board composition of the part presumed to be the restored part and the part presumed to have had existing Jangseog. In addition, it was confirmed that the joints were connected in a Majdaeim(part to part). Based on the survey results, a total of 14 pieces, including 9 Sutra boxes, 3 boxes, and 2 small boxes, that remain from the Goryeo Dynasty were classified by type and examined for similarity. Among them, there is a "Chrysanthemum Vine Pattern Sutra Box" from a private collection in Japan, a "Black Lacquered Chrysanthemum Arabesque Bun Sutra Box" from the Tokugawa Art Museum, a "Sutra Holder" from the British Museum, and a "Small Box with a Mother-of-Pearl Chrysanthemum Vine Pattern" from a private collection in Korea. The pattern composition of five points was most similar to the subject of this study. As a result of comparing the damage pattern, formative characteristics, and structural features of each part, it is presumed that the sutra holder in the British Museum was transformed into its current form from the original the chrysanthemum vine patterned box. Lastly, in order to confirm the purpose of production, that is, the use of this box, we investigated examples of Tripitaka Koreana printed version produced at a time similar to the social atmosphere of Goryeo at the time. Following the Mongol(元) invasion after the Goryeo military regime at the time, sutras appeared to pray for the stability of the nation and the soul of an individual, and with the development of domestic printing and paper in the 13th century, it gradually coincided with the transition from a scroll to a folded form, and the form of a box changed from a box. It is believed that the storage method also changed.

• Journal of Korean Society of Archives and Records Management
• /
• v.1 no.2
• /
• pp.57-79
• /
• 2001

[Go-Choseon], the first volume of Samgukyusa, is composed of two parts, the part of myth and that of history. There are very similar divinities between Hwanwoong in the myth of Dangun and YanDi-ShenNong of China: the solar divinity essential for survival of mankind and agriculture, the agriculture divinity said to have taught fanning, the medicine divinity said to have taught the characteristics of herbs and how to prevent diseases, the cultural hero who delivered civilization, and son on. During the transition from the age of myth to the age of history, the roles of gods had changed from the creation of the world to civilization and rule. The roles of Hwanwoong and YanDi-ShenNong were civilization and it was related with their divinities. Hence, regardless of a little difference, the myth of Hwanwoong and that of YanDi-ShenNong were created at the same stage of spiritual and material civilizations of Korea and China. This paper looks at the essence of [Wiseo] and the age of Hwanwoong through historical records. In my opinion, [Wiseo] is not a chinese history' book. The record, "According to [Wiseo] there had been Dangun-Wanggum 2,000 years ago" indicates the time [Wiseo] was written. 'Wi' means Wlman-choseon. Going back about 2,000 years from Wiman-choseon, the historical dates of the establishment of [Go-Choseon] almost dovetails to the age of King 'lao. So, there is a possibility that [Wiseo] is a history book of Wiman-Choseon dynasty which was written to prove the legitimacy of the dynasty by showing it succeeded to the Dangilll-Choseon dynasty. The sentences, "governed the country for 1,500 years" and "conferred Gija the position of king of Choseon" are very important records showing the age of the establishment of Dangun-Choseon. Gija came to Choseon in B.C 1122 when Yin replaced Zhou in the Choinese Continent. From the fact that Dangun had governed Choseon, we could reason out that Go-Choseon was established in B.C. 2622 that is much eariler than the era of king Yao, and that corresponds 'With the era of HuangDi(B.C 2698-2358). Hence, the era of Hwanwoong, the father-god of Dangun, might be later than B.G 3000 which conforms to the era of YanDi-ShenNong(B.C 3218-2600). Therefore, this paper contends lhat Hwanwoong and YanDi-ShenNong played the role of civilization in the same era [Go-Choseon], the first volume of Samgukusa is philologically very valuable material for research on the origin of Korean nation and its ancient history.

• The Korean Journal of Air & Space Law and Policy
• /
• v.35 no.2
• /
• pp.3-40
• /
• 2020

The term "accident" in the Warsaw Convention of 1929 and the Montreal Convention of 1999, which govern carrier liability in international air transport, is an important criterion for determining carrier liability. However, because there is no explicit definition of the term in the treaty provisions, the term is largely subjected to the judgment and interpretation of the courts. Although there have been numerous changes in purpose and circumstance in the transition from the Warsaw regime to the conclusion of the Montreal Convention, there was no discussion on the concept of "accident" therefore, even after the adoption of the Montreal Convention, there is no doubt that the term is to be interpreted in the same manner as before. On this point, the United States Supreme Court's Air France v. Saks clarified the concept of "accident" and is still cited as an important precedent. Recently, the CJEU, in GN v. ZU, presented a new concept of "accident" introduced in the Montreal Convention: that "reference must be made to the ordinary meaning" in interpreting "accident" and that the term "covers all situations occurring on aboard an aircraft." Furthermore, the CJEU ruled that the term does not include the applicability of "hazards typically associated with aviation," which was controversial in previous cases. Such an interpretation can be reasonably seen as the court's expansion of the concept of "accident," with a focus on "protecting consumer interests," a core tenet of both the Montreal convention and the European Union Regulations(EC: No 889/2002). The CJEU's independent interpretation of "accident" is a departure from the Warsaw Convention and the Saks case, with their focus on "carrier protection," and instead focuses on the "passenger protection" standard of the Montreal Convention. Consequently, this expands both the court's discretion and the carrier's risk management liability. Such an interpretation by the CJEU can be said to be in line with the purpose of the Montreal Convention in terms of "passenger protection." However, there are problems to be considered in tandem with an expanded interpretation of "accident." First, there may be controversy concerning "balance" in that it focused on "passenger protection" in relation to the "equitable balance of interests" between air carriers and passengers, which is the basic purpose of the agreement. Second, huge losses are expected as many airlines fly to countries within the European Union. Third, there is now a gap in the interpretation of "accident" in Europe and the United States, which raises a question on the "unity of rules," another basic tenet of the Convention. Fourth, this interpretation of "accident" by the CJEU raises questions regarding its scope of application, as it only refers to the "hazards typically associated with aviation" and "situations occurring aboard an aircraft." In this case, the CJEU newly proposed a novel criterion for the interpretation of "accident" under the Montreal Convention. As this presents food for thought on the interpretation of "accident," it is necessary to pay close attention to any changes in court rulings in the future. In addition, it suggests that active measures be taken for passenger safety by recognizing air carriers' unlimited liability and conducting systematic reforms.

• Journal of the Korean BIBLIA Society for library and Information Science
• /
• v.26 no.1
• /
• pp.135-170
• /
• 2015

This study aimed to investigate the transition of academic libraries' jobs by developing a model based on a shift of library generations including Library 1.0, Library 2.0, and Library 3.0 corresponding to the shift of web generations and to explore generational characteristics of library duties as well. The research used three phases of procedure: literature review about different library generations; job analyses for academic libraries in South Korea and the U.S.A.; the Delphi technique in tree sequential order. The research findings were as follows. First of all, there were 170 duties that continued from Library 1.0 to Library 3.0. There were 58 duties which continued from Library 2.0 to Library 3.0 whereas three duties that continued from Library 1.0 to Library 2.0. In addition, three distinctive duties existed only in Library 1.0 whereas one unique duty was only in Library 2.0. Library 3.0 generated 25 new duties. Secondly, considering general characteristics which cover specific parts of individual duties, there was a significant increase in importance, difficulty, and frequency of library administration throughout the three generations. In terms of importance, difficulty, and frequency of collection development and management, there was a significant increase only from Library 2.0 to Library 3.0. Considering information organization, there was a significant decrease in importance from Library 1.0 to Library 2.0. In addition, there was a significant decrease in frequency and there was no significant difference in difficulty throughout the three generations. In the case of information service, while there was a significant increase in importance among three generations, there was a significant increase in difficulty only from Library 1.0 to Library 2.0. However, there was no generational difference in frequency. With the respect of information system development and management, there was a significant increase in importance and frequency throughout the three generations, but there was no significant difference in difficulty among three generations.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.44 no.6
• /
• pp.26-39
• /
• 2016

This research paper explores the process of developing skateboarding spaces in urban parks. Skateboarding is one of the most popular sport activities representative of urban parks. This research paper will analyze the process of introducing skateboarding activities into park spaces and their acceptance by the general public as well as derive meaningful general implications for park space development planning. The research method is a discourse analysis of newspaper articles regarding skateboarding issued between the 1960s and 2010s. These articles are the main resources to show the creation of a skateboarding culture, generation of skate park spaces, and the extinction of these spaces during the research period. The result of this research is as follows. There are reasons that allowed for the creation of skate park spaces in urban parks. First of all, positive associations that people have regarding skateboarding have influenced the park's users and operators' decisions that a park is proper space for skateboarding activities, and the agreement to remodel the park space. Secondly, skate parks became a space for multiple-uses that can be shared with other emerging sports, which resulted in a building boom of skateboarding spaces in urban parks. Thirdly, urban parks and their new culture of active sports became a marketing tool used by local governments to attract new inhabitants to their new towns. On the contrary, there are three main reasons for the deterioration of skate parks. First of all, within parks in which skateboarding activities collided with other park usage, the skate parks disappeared. Secondly, skate parks built specifically for competitive skateboarding events and without consideration of casual skaters disappeared, as these facilities were not sustainable for use in the long term. Thirdly, the golden age of skate park skateboarding did not last long, as skateboarding trends shifted from trick performance to street skating, where skate parks are no longer needed. For this reasons, the exclusive use of park space for skateboarding activities has faded from public interest. The findings of this research suggest how sport activities should be introduced to urban parks. At first, each park's management needs to identify a sport suitable for long-term development, and not only plan for temporal events or follow fleeting trends. Secondly, the park's management systems should reflect a type of sport activity that would not only be popular at the beginning of the spaces development, but also take into consideration how these activities will change over time. Lastly, in cases where there are conflicts between sport activities and other activities in urban parks, attempts should be made to suggest feasible solutions other than the liquidation of sport spaces. This study explains the development process of sport spaces offered in urban parks, by thorough research of the process of acceptance of skateboarding activities in current urban park systems. This conclusion also indicates further areas for research with the purpose of understanding general best practices in urban parks sport space planning.

• Management & Information Systems Review
• /
• v.34 no.3
• /
• pp.17-39
• /
• 2015

This study examined the structural changes and volatility in the global stock markets using a Markov Regime Switching ARCH model developed by the Hamilton and Susmel (1994). Firstly, the US, Italy and Ireland showed that variance in the high volatility regime was more than five times that in the low volatility, while Korea, Russia, India, and Greece exhibited that variance in the high volatility regime was increased more than eight times that in the low. On average, a jump from regime 1 to regime 2 implied roughly three times increased in risk, while the risk during regime 3 was up to almost thirteen times than during regime 1 over the study period. And Korea, the US, India, Italy showed ARCH(1) and ARCH(2) effects, leverage and asymmetric effects. Secondly, 278 days were estimated in the persistence of low volatility regime, indicating that the mean transition probability between volatilities exhibited the highest long-term persistence in Korea. Thirdly, the coefficients appeared to be unstable structural changes and volatility for the stock markets in Chow tests during the Asian, Global and European financial crisis. In addition, 1-Step prediction error tests showed that stock markets were unstable during the Asian crisis of 1997-1998 except for Russia, and the Global crisis of 2007-2008 except for Korea and the European crisis of 2010-2011 except for Korea, the US, Russia and India. N-Step tests exhibited that most of stock markets were unstable during the Asian and Global crisis. There was little change in the Asian crisis in CUSUM tests, while stock markets were stable until the late 2000s except for some countries. Also there were stable and unstable stock markets mixed across countries in CUSUMSQ test during the crises. Fourthly, I confirmed a close relevance of the volatility between Korea and other countries in the stock markets through the likelihood ratio tests. Accordingly, I have identified the episode or events that generated the high volatility in the stock markets for the financial crisis, and for all seven stock markets the significant switch between the volatility regimes implied a considerable change in the market risk. It appeared that the high stock market volatility was related with business recession at the beginning in 1990s. By closely examining the history of political and economical events in the global countries, I found that the results of Lamoureux and Lastrapes (1990) were consistent with those of this paper, indicating there were the structural changes and volatility during the crises and specificly every high volatility regime in SWARCH-L(3,2) student t-model was accompanied by some important policy changes or financial crises in countries or other critical events in the international economy. The sophisticated nonlinear models are needed to further analysis.

• Journal of Bio-Environment Control
• /
• v.31 no.4
• /
• pp.485-496
• /
• 2022

Modern agriculture is being transformed into smart agriculture to maximize production efficiency along with changes in the 4th industrial revolution. However, rural areas in Korea are facing challenges of aging, low fertility, and population outflow, making it difficult to transition to smart agriculture. Among ICT technologies, simulation allows users to observe or experience the results of their choices through imitation or reproduction of reality. The combination of the three-dimension (3D) model and the greenhouse simulator enable a 3D experience by virtual greenhouse for fruits and vegetable cultivation. At the same time, it is possible to visualize the greenhouse under various cultivation or climate conditions. The objective of this study is to apply the greenhouse climate management model for simulation development that can visually see the state of the greenhouse environment under various micrometeorological properties. The numerical solution with the mathematical model provided a dynamic change in the greenhouse environment for a particular greenhouse design. Light intensity, crop transpiration, heating load, ventilation rate, the optimal amount of CO₂ enrichment, and daily light integral were calculated with the simulation. The results of this study are being built so that users can be linked through a web page, and software will be designed to reflect the characteristics of cladding materials and greenhouses, cultivation types, and the condition of environmental control facilities for customized environmental control. In addition, environmental information obtained from external meteorological data, as well as recommended standards and set points for each growth stage based on experiments and research, will be provided as optimal environmental factors. This simulation can help growers, students, and researchers to understand the ICT technologies and the changes in the greenhouse microclimate according to the growing conditions.

• Korean Journal of Environment and Ecology
• /
• v.36 no.6
• /
• pp.651-661
• /
• 2022

Plants social network analysis, which combines plants society and social network analyses, is a new research method for understanding plants society. This study was conducted to investigate the relationship between species, using plant social network analysis targeting Taejongdae in Busan, and build basic data for management. Taejongdae, located in the warm temperate forest in Korea, is a representative coastal forest of Busan Metropolitan City, and the Pinus thunbergii-Eurya japonicacommunity is widely distributed. This study set up 100 quadrats (size of 100m²each) in Taejongdae to investigate the species that emerged and analyzed the interspecies association focusing on major species. Based on the results, a sociogram was created using the Gephi 0.9.2, and the network centrality and structure were analyzed. The results showed that the frequency of appearance was high in the order of P. thunbergii, E. japonica, Quercus serrata, Sorbus alnifolia, Ligustrum japonicum, and Styrax japonicusand that many evergreen broad-leaved trees appeared due to the environmental characteristics of the site. The plants social network of Taejongdae was composed of a small-scale network with 50 nodes and 172 links and was divided into 4 groups through modularization. The succession sere identified through a sociogram confirmed that the group that include P. thunbergiiand E. japonicawould progress to a deciduous broadleaf community dominated by Q. serrataand Carpinus tschonoskii, using hub nodes such as Prunus serrulataf. spontaneaand Toxicodendron trichocarpum. Another succession sere was highly likely to progress to an evergreen broad-leaved community dominated by Machilus thunbergiiand Neolitsea sericea, using M. thunbergiias a medium. In some areas, a transition to a deciduous broad-leaved community dominated by Celtis sinensis, Q. variabilisand Zelkova serratausing Lindera obtusilobaand C. sinensisas hub nodes was expected.