• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.3
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• pp.73-82
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• 2017

As of December 2016, the number of registered automobiles in Korea exceeds 21million. As a result, greenhouse gas emission by transportation sector are increasing every year. It was concluded that the development of the driving strategy considering the driving behavior and the road conditions, which are known to affect the fuel efficiency and the greenhouse gas emissions, could be the most effective fuel economy improvement. Therefore, this study aims to develop a fuel efficient driving strategy in a complex linear section with uphill and curved sections. The road topography was designed according to 'Rules about the Road Structure & Facilities Standards'. Various scenarios were selected. After generating the speed profile, it was applied to the Comprehensive Modal Emission Model and fuel consumption was calculated. The scenarios with the lowest fuel consumption were selected. After that, the fuel consumption of the manual driver's driving record and the selected optimal driving strategy were compared and analyzed for verification. As a result of the analysis, the developed optimal driving strategy reduces fuel consumption by 21.2% on average compared to driving by manual drivers.

• 한국노년학
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• v.39 no.3
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• pp.467-484
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• 2019

The purpose of this study is to explore latent classes of longitudinal medical expenses of older people and to analyze its predictors and its effects on subjective health. Among participants of the Korean Health Panel, the sample of this study includes 1,119 people who is 65-year-old or older and reported their medical expenses for nine consecutive years. The analyses were conducted in three steps. First, Growth Mixture Model (GMM) was applied to find distinct subgroups showing similar patterns in medical expenses. The results showed four groups which were classified as high medical expenditure maintenance group, medical expenditure increase group, low medical expenditure maintenance group, and medical expenditure reduction group. Second, the multinominal logistic regression found that the presence of spouse, economic participation, the number of chronic diseases, and the type of health insurance were significant predictors of latent classes in medical expenses. In particular, the greater the number of chronic diseases, the higher the likelihood of belonging to the high medical expenditure maintenance group. In addition, medical benefit recipients are more likely to belong to the low medical cost maintenance and medical cost reduction groups. Third, multiple regression analysis revealed that the older people in the groups with low or reducing expenses reported better subjective health than people with higher expenses. This study has its meanings in exploring the heterogeneity in longitudinal medical expenses among older people and its predictors and its associations with health outcome. The results of this research provide background information in establishing public health policy for older people.

• Journal of the Daesoon Academy of Sciences
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• v.37
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• pp.1-52
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• 2021

The Naejeong, the inner court, which is one of the structures found in the temple complexes of Daesoon Jinrihoe. It serves the function of leading and controlling the operation and direction of Korean religions in general. Considering that the dictionary meaning of 'Naejeong' is 'a place to manage the affairs of the state from inside a palace,' the name and function of the structure appear to be in harmony. However, in the Daesoon Jinrihoe context, it is said that the name 'Naejeong (內庭 'Neiting' in Chinese)' is related to a verse from a Daoist scripture. It has not been revealed whether or not the scripture is historical, and what contents or contextual meanings it contains. This study tries to pursue this matter and introduce the original source of the Naejeong in Daesoon Jinrihoe as likely coming from Qianbapinxianjing (前八品仙經, The Former Scripture of the Eight Phases That Reveal the Means to Acquire Immortality). This scripture was compiled in Lüzu-quanshu(呂祖全書, The Entire Collection of Ancestor Lü). This text and its contextual meanings will also be examined. The origin of Qianbapinxianjing dates back to either the late Ming Dynasty or the early Qing. In those days, there existed a group of literati who worshipped Ancestor Lü because he had saved people and taught the art of immortality. The group organized Daoist Spirit-Writing Altars (鸞壇道敎) and invoked the spirit of Ancestor Lü. They were said to have been taught through messages received from spirit-writing sessions (降乩) with Ancestor Lü and several Daoist scriptures were composed by them in this manner. At Immortals-Gathering Pavilion (集仙樓) of Wandian (萬店) in Guangling (廣陵), China, some literati in that group conducted a spirit-writing session with Ancestor Lü between 1589 and 1626, and they produced a scripture which contained the passage, "A crow and a rabbit gather in the middle valley (烏兎結中谷) while a turtle entwined with a snake is in the inner court (龜蛇盤內庭)." They titled the scripture, The Five Movements and Filial Piety (五行端孝). This passage symbolically expresses the accomplishment of immortality in Neidan (internal alchemy) which, within the human body, combines the two energies of yin and yang which are Water and Fire in the Five Movements scheme. This kind of cultivation is said to be achieved only by maintaining the highest possible degree of filial piety. In this context, the Naejeong where a turtle is entwined with a snake (龜蛇合體) was a term that symbolically depicted a place wherein one transforms into an immortal through cultivation. The Five Movements and Filial Piety was included in Qianbapinxianjing after it had been compiled with the other scriptures containing Ancestor Lü's teachings. In 1744, Qianbapinxianjing was included in Lüzu-quanshu, the entire 32-volume collection of Ancestor Lü and printed for the first time. This underlies the belief in Ancestor Lü (呂祖信仰) which embraces the idea of the redemption of people, teaches the arts of immortality, and features Daoist Spirit-Writing Altars, filial piety, the art of Neidan, and the combination of Water and Fire.

• Journal of the Korean Regional Science Association
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• v.34 no.2
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• pp.3-19
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• 2018

The objective of this study is to observe the efficiency of clinical performance on the supply and demand of medical resources in Korea. For the empirical analysis, we constructed the dataset on age standardized mortality rate, the number of physician, specialist, surgery, medical institution, ratio of general hospitals of 16 provinces in Korea from 2006 to 2013. The panel probability frontier model is employed as an analysis method and considered heteroscedasticity and autocorrelation of the error in panel data. In addition, the demographic and socioeconomic characteristics of the 16 provinces, unemployment rate, elderly population ratio, GRDP per capita, and ratio of hospitals in comparison to the general hospitals are used to find the effect on the technical efficiency of clinical performance on supply and demand of medical resources. The results are as follows. First, for the clinical performance, the supply side of human resources such as doctors and specialists and the demand side factors such as chronic illness clinic per unit population have a significant influence, respectively. Second, the technical efficiency of clinical performance on the supply and demand of medical resources of each input component was 59-70% in terms of clinical efficiency in each region. Third. estimates of technical efficiency of inputs that affect clinical performance showed a slight increase in all regions during the analysis period, but the increase trend decreased slightly. Fourth, the ratio of the elderly population and GRDP per capita have a positive influence on the technical efficiency of clinical performance on the supply and demand of medical resources. The difference of each efficiency by region is due to the regional differences of the input medical resources and the combination of them and the demographic and socioeconomic characteristics of the region. It is understood that the differences in technological efficiency due to the complexity of supply and demand of medical resources, demographic structure and economic difference affecting clinical performance by region are different.

• Pediatric Infection and Vaccine
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• v.30 no.2
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• pp.73-83
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• 2023

Purpose: This study aimed to investigate the viral load dynamics in children with underlying malignancies diagnosed with symptomatic coronavirus disease 2019 (COVID-19). Methods: This was a retrospective longitudinal cohort study of patients <19 years old with underlying hemato-oncologic malignancies that were diagnosed with their first symptomatic severe acute respiratory syndrome coronavirus 2 polymerase chain reaction (PCR)-confirmed COVID-19 infection during March 1 to August 30, 2022. Review of electronic medical records and telephone surveys were undertaken to assess the clinical presentations and transmission route of the patients. Thresholds of negligible likelihood of infectious virus was defined as E gene reverse transcription (RT)-PCR cycle threshold (Ct) value ≥25. Results: During the 6-month study period, a total of 43 children with 44 episodes of COVID-19 were included. Of the 44 episodes, the median age of the patients included was 8 years old (interquartile range [IQR], 4.9-10.5), and the most common underlying disease was acute lymphoid leukemia (n=30, 68.2%), followed by patients post-hematopoietic stem cell transplantation (n=8, 18.2%). Majority of the patients had mild COVID-19 (n=32, 72.7%), and three patients (7.0%) had severe/critical COVID-19. Furthermore, 2.3% (n=1) died of COVID-19 associated acute respiratory distress syndrome. The largest percentage of the patients showed E gene RT-PCR Ct value ≥25 between 15-21 days (n=13, 39.4%), followed by 22-28 days (n=10, 30.3%). In 15.2% (n=5), E gene RT-PCR Ct value remained <25 beyond 28 days after initial positive PCR. Refractory malignancy status (β, 67.0; 95% confidence interval, 7.0-17.0; P=0.030) was significantly associated with prolonged duration of E gene RT-PCR <25. A patient with prolonged duration of E gene RT-PCR Ct value <25 was suspected to have infectivity shown by the transmission of the virus to his mother at day 86 after his initial positive test. Conclusions: Children that acquire symptomatic COVID-19 during refractory malignancy state are at a high risk for prolonged shedding warranting PCR-based transmission precautions in this cohort of patients.

• Journal of The Korean Association For Science Education
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• v.42 no.3
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• pp.371-381
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• 2022

This study causally investigates whether high school student with high science learning motivation becomes to achieve more or vice versa, and also how those two factors affect STEM career motivation. Research participants were 1st year students in a high school at Seoul. We surveyed their science learning motivation three times in the same time interval in the fall semester of 2021, and once a STEM career motivation in the third period. We collected data from 171 students with their mid-term and final exam scores, with which, we constructed and fitted an autoregressive cross-lagged model. The research model shows high measurement stability and fit indices. All the autoregressive and cross-lagged paths were statistically significant. However, standardized regression coefficients were larger in path from motivation to achievement compared to the opposite. Only science learning motivation shows significant direct effect on STEM career motivation, rather than achievement. For indirect effects, the first science learning motivation affected the final exam score and STEM career motivation, and the final exam score affected STEM career motivation. However, the final exam score did not have a total effect toward STEM career motivation. The result of this study shows reciprocal and cyclic causality between science learning motivation and achievement - in comparison, the effect of motivation for the opposite is larger than that of achievement. Also the result of this study strongly reaffirms the importance of science learning motivation. Instructional implications for strengthening science learning motivation throughout a semester was discussed, and a study for the longitudinal effect of science learning motivation and achievement in high school student toward future STEM vocational life was suggested.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.16 no.4
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• pp.25-58
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• 2021

This study investigated the corporate growth with more emphasis on longitudinal characteristics, not the results of companies with relatively more emphasis on cross-sectional, in the 21st-century entrepreneurial context. As of the end of 2019, sampled 479 global unicorn companies, and 333 high-growth companies with revenue of more than $100 million among 5,000 private companies in the U.S. with a compound annual growth rate (CAGR) exceeding 15% for the past three years. They were examined with 3 perspectives in terms of corporate growth that 1) the growth of enterprise value, 2) the pace of growth, and 3) the effectiveness of growth. As a result of our study, the corporate growth of the perspective of creating enterprise value had a relatively higher relationship with the characteristics of industries and markets. The pace of growth was more fully explained by the characteristics of the industry and the market environment and the choice of strategies that make up a valid combination. In addition, growth in terms of the effectiveness of corporate performance was influenced by the choice of strategy, the characteristics of the industry and market environment, and its business age, the proxy variable of resource accumulation, comprehensively. This study through a sample based on companies with an enterprise value of more than $1 billion and annual revenue of more than $100 million can be a valid reference in terms of creating milestones and roadmaps for scale-up of early-stage startups, particularly in terms of practitioners' point of view. It also provides a critical reference for overcoming the limitations of mainstream theories of the 20th century and developing the theory of corporate growth that fits the 21st-century entrepreneurial context.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.40 no.3
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• pp.20-35
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• 2022

This study was conducted on the locational results of the 'Yusanggoksu(流觴曲水)' petroglyphs located in Hwanggak-dong(黃閣洞), Shinsong-ri, Geumma-myeon, Iksan-si through literature study, analysis of old maps and aerial photos, field observations, drone photography, elevation surveys, and interviews with residents. It was attempted for the purpose of illuminating and preserving the relics of the domestic Yusanggoksu garden by clarifying the spatiality of this place by tracing the spatiality and examining the possibility of enjoying the Yusanggoksu water system in this place. The conclusion of this study is as follows. The area around Hwanggak-dong, where the Yusanggoksu remains, has been selected as the most beautiful scenic spot in Iksan in various documents. The origin of 'Hwanggak' is considered to be closely related to the nickname of Uijeongbu(議政府). In other words, he paid attention to the relationship with Yanggok, So Se-yang(蘇世讓), who served as Chan-seong Jwa(左贊成). In particular, he paid attention to the relationship with his birthplace, Taeheojeong, a separate book, and Toehyudang, a retreat hall), tombs, and posthumous Confucian academies were distributed in the vicinity. Haseo-dae(荷鋤臺), a wide rock on which a hoe is hung on a rock after field work, seems to express a leisurely rural life and a simple and hermit life, based on the examples of Chinese and Korean poetry. The dark blood on the upper part of the Seobwi Rock with the inscription 'Yusanggoksu', which is the core of this site, is identified as a chailgong(遮日孔) to support the water system, and Ilgan-pavilion and Mojeong(茅亭) nearby are to support the yusanggoksu. It seems to have performed a spatial function for The inscription 'Hwanggak-dong' engraved on the front of Deungzanbawi is the gateway to Hwanggakdongcheon(黃閣洞天) and identified the idealized world existing in the village. Judging from the documentary records of the Iksan-gun 『Chongswaelog(叢瑣錄)』, the rock letters 'Hwanggak-dong' and 'Haseodae' were engraved on March 29, 1901, the 5th year of Gwangmu, the 5th year of the Korean Empire, by Iksan-gun Governor Oh Haeng-mook(吳宖默) and his acquaintance Seokseong Kim In-gil(金寅吉) Confirmed. Also, considering the tense of Lee Bong-gu's 「Hwanggakdongun(黃閣洞韻)」 and So Jin-deok, a descendant of Yanggok, 「Hwanggakdongsihoe(黃閣洞詩會)」, it is presumed that it was related to Goksuyeon(曲水宴) in Hwanggak-dong. It can be inferred that the current affairs meetings were held at least until the early days of Japanese colonial rule. Meanwhile, the maximum width of the current curved waterway was calculated as 11.3m and the transverse slope was 15.0%. If so, it is estimated that the width and extension distance of the curved waterway would have been much longer. Judging from the use of mochun(暮春), drinking and poetry, the tense 'Hwanggakdongsihoe' related to the Yusanggoksu relics in Hwanggak-dong, and the existence of a pavilion presumed to be Yusangjeong(流觴亭) called Ilgan-pavilion in the nearby Yusanggoksu site It is confirmed that it was a space where Yusanggoksuyeon(流觴曲水宴) spread at least until the end of the Joseon Dynasty. Unfortunately, it remains a limitation of the study that it cannot be confirmed due to lack of data on the rock characters of 'Yusanggoksu' and those who enjoyed it before the end of the Joseon Dynasty. This is an area that needs to be elucidated through continuous efforts to find data on this issue in the future.

• Journal of the Mineralogical Society of Korea
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• v.32 no.3
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• pp.163-172
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• 2019

A long core (RS15-LC48) was collected at a site in the continental rise between the Southern Ocean and the Ross Sea (Antarctica) during the 2015 Ross Sea Expedition. The mineralogical characteristics and the origin of clay minerals in marine sediments deposited during the Quaternary in the Ross Sea were determined by analyzing sedimentary facies, variations in grain size, sand fraction, mineralogy, clay mineral composition, illite crystallinity, and illite chemical index. Core sediments consisted mostly of sandy clay, silty clay, or ice rafted debris (IRD) and were divided into four sedimentary facies (units 1-4). The variations in grain size distribution and sand content with depth were very similar to the variations in magnetic susceptibility. Various minerals such as smectite, chlorite, illite, kaolinite, quartz, and plagioclase were detected throughout the core. The average clay mineral composition was dominated by illite (52.7 %) and smectite (27.7 %), with less abundant clay minerals of chlorite (11.0 %) and kaolinite (8.6 %). The IC and illite chemical index showed strong correlation trends with depth. The increase in illite and chlorite content during the glacial period, together with the IC and chemical index values, suggest that sediments were transported from the bedrocks of the Transantarctic Mountains. During the interglacial period, smectite may have been supplied by the surface current from Victoria Land, in the western Ross Sea. High values for IC and the illite chemical index also indicate relatively warm climate conditions during that period.

• Journal of the Mineralogical Society of Korea
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• v.31 no.1
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• pp.1-12
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• 2018

A gravity core (RS14-C2) was collected at site RS14-C2 in the continental slope to the east of Pennell-Isellin Bank of the Ross Sea (Antarctica) during PNRA XXIX (Rosslope II Project) Expedition. In order to trace the sediment source, magnetic susceptibility (MS), sand fraction, and clay mineral compositions were analyzed, and AMS $^{14}C$ ages were dated. Core sediments consist mostly of hemipelagic sandy clay or silty clay including ice-rafted debris (IRD). AMS $^{14}C$ age of core-top indicates the modern and Holocene sediments. Based on AMS $^{14}C$ dating, sediment color, MS and sand fraction, core sediments are divided into interglacial and glacial intervals. The interglacial brown sediments are characterized by low MS and sand fraction, whereas the glacial gray sediments are characterized by high MS and sand fraction. Among clay mineral compositions of core sediments, illite is highest (61.8~76.7%), and chlorite (15.7~21.3%), kaolinite (3.6~15.4%), and smectite (0.9~5.1%) are in decreasing order, and these compositions are also divided into the interglacial and glacial/deglacial intervals. During the glacial period, the high content of illite and chlorite indicate sediment supply from the bedrocks of Transantarctic Mountains under the Ross Ice Sheet. In contrast, because of decreasing supply of illite and chlorite by the glacial retreat, smectite and kaolinite contents increased relatively during the interglacial period. During the interglacial period, smectite may be transported additionally by the northeastward flowing surface current from the coast of Victoria Land in the western Ross Sea. Kaolinite may be also supplied to the continental slope by the Antarctic Slope Current from the kaolin-rich metasedimentary rock outcropped on the Edward VII Peninsula.