• The Journal of Korean Academy of Prosthodontics
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• v.55 no.4
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• pp.381-388
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• 2017

Purpose: Unpredictable shrinkage of zirconia during sintering process causes discrepancy. Therefore, there have been attempts to reduce discrepancy by milling zirconia after sintering. However, due to the hardness of sintered zirconia, milling takes longer time, causes damage to the machine and causes chip formation. With customized zirconia block using the mean dimension of prepared natural dentition, it is expected to overcome these shortcomings. Materials and methods: The mean dimension of prepared natural dentition was analyzed as STL file after scanning of prepared teeth treated at SNUDH. The transverse, frontal and sagittal planes were set using Mimics and Photoshop. 3D volume was projected on each plane, and the outer line was measured through external tangent line, and the inner line was measured through inflection point of tangent line. Results: The mean height of prepared incisal (N = 57) is $6.60{\pm}1.05mm$, mesiodistal length is $2.98{\pm}0.73mm$, buccolingual length is $2.04{\pm}0.73mm$. The mean height of prepared premolar (N = 15) is $5.37{\pm}1.49mm$, mesiodistal length is $4.10{\pm}1.78mm$, buccolingual length is $5.86{\pm}1.55mm$. And the mean height of prepared molar (N = 13) is $5.11{\pm}1.29mm$, mesiodistal length is $6.80{\pm}1.18mm$, buccolingual length is $7.34{\pm}1.40mm$. Conclusion: Using the mean dimension of prepared natural dentition, it is expected to be able to fabricate customized zirconia block.

• The Journal of the Society of Korean Medicine Diagnostics
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• v.12 no.1
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• pp.42-62
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• 2008

Objectives: It is well known that some parameters of the photoplethysmogram (PPG) acquired by time domain contour analysis can be used as markers of vascular aging. But the previous studies that have been performed for frequency domain analysis of the PPG to date have provided only restrictive and fragmentary information. The aim of the present investigation was to determine whether the harmonics extracted from the PPG using a fast Fourier transformation could be used as an index of vascular aging. Methods: The PPG was measured in 600 recruited subjects for 30 second durations, To grasp the gross age-related change of the PPG waveform, we grouped subjects according to gender and age and averaged the PPG signal of one pulse cycle. To calculate the conventional indices of vascular aging, we selected the 5-6 cycles of pulse that the baseline was relatively stable and then acquired the coordinates of the inflection points. For the frequency domain analysis we performed a power spectral analysis on the PPG signals for 30 seconds using a fast Fourier transformation and dissociated the harmonic components from the PPG signals. Results: A final number of 390 subjects (174 males and 216 females) were included in the statistical analysis. The normalized power of the harmonics decreased with age and on a logarithmic scale reduction of the normalized power in the third (r=-0.492, P<0.0001), fourth (r=-0.621, P<0.0001) and fifth harmonic (r=-0.487, P<0.0001) was prominent. From a multiple linear regression analysis, Stiffness index, reflection index and corrected up-stroke time influenced the normalized power of the harmonics on a logarithmic scale. Conclusions: The normalized harmonic power decreased with age in healthy subjects and may be less error prone due to the essential attributes of frequency domain analysis. Therefore, we expect that the normalized harmonic power density can be useful as a vascular aging marker.

• Korean journal of applied entomology
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• v.42 no.3
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• pp.173-184
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• 2003

Beetles belonging to the families Scolytidae, Platypodidae, Bostrichidae, and Lyctidae intercepted from imported timbers at Busan port were investigated from March 1 to November 30 in 2000. In addition, hosts imported country were examined. A total of 52 species of within 23 genera was intercepted from nineteen species of timbers or logs from fifteen countries. In Scolytidae, 35 species of 16 genera in three subfamilies were identified 12 species in Xyleborus, 6 species in Ips, 3 species in Trypodendron, 2 species in Arixyleborus, and 12 species of all different genera including Alinphagous. Scolytidae were intercepted from 16 species of timbers in 13 genera imported from 11 countries. The highest beetles were intercepted from Malaysian lauan. In Platypodidae, 9 species of one genus (Platypus) were intercepted from 6 species of timbers in 4 genera imported from 6 countries including Australia. The highest numbers were intercepted from Malysian lauan. In Bostrychidae, 5 species of 4 genera in two subfamilies were intercepted from 6 species of timbers in 4 genera imported from four countries. In Lyctidae, Trogoxylon sp., Minthea sp., and Minthea rugicollis were intercepted from 3 species of timbers in 2 genera imported from 3 countries.

• 한국노년학
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• v.38 no.4
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• pp.811-835
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• 2018

Social relations and cognitive function in old age are closely related to each other, and social relation is classified into structural characteristics and qualitative characteristics reflecting cognitive and emotional evaluation. The concept of social isolation is the focus of attention in relation to the social relations of old age. Social isolation has a multidimensional theoretical structure that is divided into objective dimension such as social network, type of furniture, social participation, and subjective dimension such as lack of perceived social support and loneliness. There is also a close relationship between cognitive function and interpersonal conflict in old age. In this study, we examined the effect of subjective social isolation, which shows the structural characteristics of social relations, and subjective social isolation and interpersonal conflict on the dementia occurrence by age group in the elderly. The data were analyzed by applying a random effect panel logit model using 1,740 panel data from the first year to the third year of KSHAP. The results of the analysis are summarized as follows. First, the cognitive impairment increased sharply with age. Objective and subjective social isolation were both U-shaped distribution with an inflection point of 80 years old. Second, the main effect on the probability of cognitive impairment was statistically significant with objective and subjective social isolation, but the type of interpersonal conflict did not appear to be significant. Third, the results of two-way interaction effect analysis on the probability of cognitive impairment are as follows. The relationship between subjective social isolation and the probability of occurrence of cognitive impairment was significantly different according to the level of conflict with spouse. In addition, the higher the subjective social isolation, the higher the probability of cognitive impairment in the elderly(over 85) than in the young-old(65~74). In addition, as the level of conflict with spouses increases, the probability of cognitive impairment of the oldest-old(aged 85 or older) is drastically lower than that of the young-old(aged 65~74). Based on the results of this study, policy and practical implications for reducing the cognitive impairment of the elderly age group were suggested, and limitations of the study and suggestions for future research were discussed.

• Journal of the Korean Institute of Landscape Architecture
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• v.49 no.5
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• pp.59-70
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• 2021

This study was to investigate the measurement point of root collar diameter of landscape trees in Korea. It may contribute to avoiding disputes caused by the difference in measurement criteria of root collar diameter of landscape trees between tree growers and constructors. The difference between landscape trees' root collar diameter measurement point was 3.59cm from 6cm underground to the surface and 1.35cm from 0cm to 6cm above ground. The source root collar diameter measurement point difference was larger in the basement than in the ground. The standard deviation of the root collar diameter of the landscape tree was 0.64 from 6cm underground to the surface, and the difference in standard deviation from 0cm to 6cm above ground was 0.16. The difference by measurement point of the root collar diameter was larger in the basement than in the ground. It has been proposed to set the reasonable measurement point of the landscaping tree root collar diameter at the inflection point where the standard deviation of the tree trunk diameter is the smallest in line with the size change of the standard for each root collar diameter measurement point. By tree species, Cornus officinalis Siebold & Zucc. 18cm above the ground, Chionanthus retusus Lindl. & Paxton. 12cm above the ground, Zelkova serrata (Thunb.) Makino. 12cm above the ground, Celtis sinensis Pers. 12cm above the ground, Styrax japonicus Siebold & Zucc. 10 cm above the ground, Cornus officinalis Siebold & Zucc. 10cm above the ground, Acer palmatum Thunb. ex Murray. 6cm above the ground, Ilex rotunda Thunb. 6cm above the ground, Quercus myrsmaefolia Blume. 4cm above the ground, Lagerstroemia indica L. 2cm above the ground The above heights were shown as reasonable measurement points. The difference by landscape tree root collar diameter measurement site showed that the standard deviation was small throughout the tree species, and the reasonable average measurement point with a stable slope of the deviation was 12cm or more on average. It can be said that the reasonable measurement point of the root collar diameter of a landscape tree is set at an average of 12cm above the ground. However, recognizing 30cm, which is a familiar ruler(尺) in traditional practices, is quick, It was recommended to measure at the height of 30cm from the surface for a reasonable measurement point of the root collar diameter of a landscape tree, for the uniformity of measurement standards.

• Journal of Popular Narrative
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• v.25 no.3
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• pp.9-40
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• 2019

This study presents an investigation into South Korean films in the 1990s in the aspects of genre change and emotional reorganization. The 1990s witnessed a change of genres and a paradigm shift in the history of Korean films according to the revolutionary changes of the film industry structure and media environment. Believing that these changes had something to do with emotional changes driven by global capitalization symbolized by democratization in 1987 and the foreign currency crisis in 1998, the investigator analyzed the phenomena in film texts and examined the opportunities and context behind them. Unlike previous researches, this study made an approach to the history of Korean films in the 1990s with three points: first, this study focused on why the romantic comedy genre emerged in the 1990s and what stages its formation underwent since there had been no profound discussions about them; secondly, this study analyzed the biggest hits during the transitional period from 1987~1999 to figure out the mainstream genres and emotions during that period since these hits would provide texts to show the genre domain and public taste in a symbolic way; and finally, this study grew out of the separate investigation approach between melodramas and romantic comedies and looked into an emotional structure to encompass both genres to make a more broad and dynamic approach to South Korean films in the 1990s. History flows continuously without severance from previous times. When there is attention paid to inflection points and opportunities in the continuum, it can show the dynamics and structures of changes. This research led to the following conclusions: the mainstream genre of South Korean films had been melodramas until the 1980s. The old convention had been kept to offset or suture contradictions and excessive elements deviant from the structural consistency. Here, the structural consistency refers to no compliance to rational regulations or trade. The process of genre reorganization in the 1990s happened while securing some distance from the convention of making the structural consistency a sacrifice. The direction was to reinforce control through reasonable rationalism and logic of capital. It developed into romance, which would start with comedy to keep distance from the objects through laughter, heighten the level of remarks, and expand criticality, symbolize emotions with taste items, and build through the logic of mutual consensus and practical trade. In the 1990s, the South Korean films thus developed in a direction of moving away from the narrative of urgent pathos based on unconditional familism. It was on the same track as the entry of the South Korean society into the upgraded orbits of democracy and capitalism as the twins of modern rationalism since the latter part of the 1980s.

• Korean Journal of Heritage: History & Science
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• v.56 no.4
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• pp.110-130
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• 2023

New years' rites serve a religious function to wish for well-being during the year by bidding farewell to the previous year and welcoming the next. In Japan, in mid-December, to welcome Toshigami, kadomatsu, and shimenawagazari are prepared, as well as osechi ryori to be eaten at the beginning of the year. On New Year's Day, people go to shrines and bow to the gods while saying Hatsumode (初詣). On the fifteenth day of the first month, in the course of a rite called Dondoyaki, all the decorations used in the first month and the amulet used in the previous year are burned. In Korea, when the Lunar New Year approaches, people prepare for their ancestral rites and clean their houses. On the first day of the new year, people hold ancestral rites for their ancestors. There are many different seasonal rites, taking place from the beginning of the year to the full moon. In China, Danwonban (團圓飯), in which the whole family sits together and eats on New Year's Eve, is important. Lights are brightly lit up all night, and the sound of firecrackers outside rings out loudly. On the door, the word chun-ryun is attached to wish for prosperity in the new year. According to the cycle of the four seasons, the first lunar month contains a high proportion of the seasonal rites that are repeated every year. The first month represents the beginning of a year, and various rituals are performed in order to wish for good health and abundance during the coming year. In addition, the "folk religious world view" is integral to annual new years' rites, so it is not difficult to understand the religious character and structure of the Korean, Chinese, and Japanese annual ceremonies. This study examines the current status of annual new years' rites in Korea, China, and Japan, and how the rites are structured according to the inflection points in the year. In addition, religious characteristics are reviewed in terms of gods, predictions, and fertility prayers, exorcisms, health, and restoration. In this way, it can be seen that various religious elements such as shamanism, agricultural faith, ancestor worship, Shintoism, Taoism, Confucianism, and Buddhism can be witnessed in the annual new years' rites of Korea, China, and Japan. In addition, differences in the presence or absence of these are shown to depend on the country.

• Korean Journal of Heritage: History & Science
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• v.57 no.2
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• pp.80-100
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• 2024

This paper investigated the major history and reality of iconological composition for Jagyeongjeon Hall's flowered wall in Gyeongbokgung Palace, which was controversial in terms of preservation and management of cultural heritage. While analyzing the moment and cause of the flowered wall's renovation as it is now, modified or disappeared patterns were identified, and meaningfully misinterpreted congratulatory phrases were reviewed. The research results can be used as meaningful basic data when discussions are made for the restoration of the wall in the future. Jagyeongjeon Hall's flowered wall has reached the present day with large and small changes, but the inflection point that had a significant impact was the Joseon Expo (朝鮮博覽會) held at Gyeongbokgung Palace in 1929. This is because the wall that remained in the Jagyeongjeon Hall area was demolished to build an exhibition hall while preparing for the expo, and it was restored after the end of the event. It is highly likely that the modification or disappearance of the patterns constituting Jagyeongjeon Hall's flowered wall was also due to the restoration process carried out after the expo. There is a view that was transformed into its current state in the process of repair work carried out after the Korean War, but it is difficult to find any meaningful circumstances and evidence. Currently, character patterns known as 'Seongnidori(聖人道理)' are arranged on the inner wall of the section from Gyeongdomun Gate(擎桃門) to Yeogangmun Gate(如岡門), but considering the design form and example, it can be read as 'Seongjasinson(聖子神孫)'. The inner wall of the section from Yeogangmun Gate to Yeonsumun Gate(燕壽門) was originally made in the form of a flowered wall, and the phrases presumed to be 'Gyegyeseungseung(繼繼繩繩)' and 'Cheonse(千世)' were arranged. In the case of the section from Yeonsumun Gate to Hamgyumun Gate(含奎門), the inner wall where the pattern has disappeared is originally composed of geometric and character patterns, and there were also phrases specified as 'Cheonsu(千壽)' and 'Mansemansu(萬世萬壽)'. On the outer wall of the section from Yeonsumun Gate to Hamgyumun Gate, there is a possibility that the phrase known as 'Nakgangmanse(樂彊萬歲)' can be read as 'Cheonsemanse(千歲萬歲)'. In addition, the current outer wall was composed of one drawing board, but in the past, two drawing boards were composed separately.

• Korean Journal of Environment and Ecology
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• v.31 no.2
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• pp.152-165
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• 2017

The greater long-tail hamster, Tscherskia triton, is widely distributed in Northern China, Korea and adjacent areas of Russia. Except for its distribution, biological characteristics related to life history, behavior, and ecological influences for this species are rarely studied in Korea. This study was conducted to obtain biological information on breeding, growth and development that are basic to species-specific studies. The study adopted laboratory management of a breeding programme for T. triton collected in Jeju Island from March, 2015 to December, 2016. According to the study results, the conception rate was 31.67% and the mice in the large cages had a higher rate of conception than those in the small cages (56.7 vs. 6.7%). The gestation period was $22{\pm}1.6days$ (ranges from 21 to27 days), and litter size ranged from 2 to 7, with a mean of $4.26{\pm}1.37$ in the species. The minimum age for weaning was between $19.2{\pm}1.4days$ (range of 18-21 days). There were no significant differences by sex between mean body weight and external body measurements at birth. However, a significant sexual difference was found from the period of weaning (21 days old) in head and body length, as well as tail length (HBL-weaning, $106.50{\pm}6.02$ vs. $113.34{\pm}4.72mm$, p<0.05; HBL-4 months, $163.93{\pm}5.42$ vs. $182.83{\pm}4.32mm$, p<0.05; TL-4 months, $107.23{\pm}3.25$ vs. $93.95{\pm}2.15mm$, p<0.05). Gompertz and Logistic growth curves were fitted to data for body weight and lengths of head and body, tail, ear, and hind foot. In two types of growth curves, males exhibited greater asymptotic values ($164.840{\pm}7.453$ vs. $182.830{\pm}4.319mm$, p<0.0001; $163.936{\pm}5.415$ vs. $182.840{\pm}4.333mm$, p<0.0001), faster maximum growth rates ($1.351{\pm}0.065$ vs. $1.435{\pm}0.085$, p<0.05; $2.870{\pm}0.253$ vs. $3.211{\pm}0.635$, p<0.05), and a later age of maximum growth than females in head and body length ($5.121{\pm}0.318$ vs. $5.520{\pm}0.333$, p<0.05; $6.884{\pm}0.336$ vs. $7.503{\pm}0.453$, p<0.05). However, females exhibited greater asymptotic values ($105.695{\pm}5.938$ vs. $94.150{\pm}2.507mm$, p<0.001; $111.609{\pm}14.881$ vs. $93.960{\pm}2.150mm$, p<0.05) and longer length of inflection ($60.306{\pm}1.992$ vs. $67.859{\pm}1.330mm$, p<0.0001; $55.714{\pm}7.458$ vs. $46.975{\pm}1.074mm$, p<0.05) than males in tail length. These growth rate constants, viz. the morphological characters and weights of the males and females, were similar to each other in two types of growth curves. These results will be used as necessary data to study species specificity of T. triton with biological foundations.

• Journal of Korean Historical Folklife
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• no.52
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• pp.7-46
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• 2017

The elderly in the Joseon Dynasty consistently attracted attention from the national herb as objects of social respect. Based on the Confucian ideology, the old man was considered to be a receiving body, since he was a person with complete character as a man. The elderly, who have the character of being a slave, transcended their status, and both the souls and the people were transcended beyond their identities and attributes and became objects of respect. The perception of the elderly is divided by age. The persons who are 50 years old and start to be in physical decline were regarded as senior citizens. However, this was just mentioned as an inflection point between the prime of manhood and senior citizens and was not defined as the elderly. As a public duty called a national work ends when they are 60 years old, the age is truly the lowest limit of senior citizens who are applicable to all the social beings. However, because their public duties end when they are 60 years old and they were regarded as general members of society, special benefits were not granted to them. In the caste system and bureaucratic society, senior citizens' treatment were differently done by age. For the senior citizens who are 70 years old, various benefits were just granted to high government officials. Bokho(復戶) and Seojeong were first given to them. And the retirement age of government officials was not specially set. It was done in the way to treat Jonno with exceptional respect by Chisa(致仕: regular retirement). It is the most respectful treatment given to high government officials and ministers. For the senior citizens who are 80 years old, Yangnoyeon(養老宴) was held for both of Yangmin and Cheonmin as an measure to treat them considerately. In addition, official ranks(官品) with social value were allowed by giving them Noinjik (老人職). Official ranks given to Seoin and Cheonin were the best Jonno(尊老) policy. However, the Jonno policy related to senior citizens was different according to position and official ranks as follows: Kings were subjected to social treatment when they were 60 years old. High government officials and royal relatives of the senior grade of the second court rank were subjected to social treatment when they were 70 years old. And general Seoin and slaves were subjected to social treatment when they were respectively 80 and 90 years old. Senior citizens were individually supported. However, social value was granted because the nation supervised it. As Bokho and Sijeong were assigned according to position and official ranks and kinds of things were different, the social limit was clearly shown. Social order was put above the ideology called Jonno thought. However, Jonno acts by age and position did not stay at the individual level and the nation took care of the senior citizens who are the members of society in various ways based on Jonno thought. Society tried to take care of the senior citizens who had difficulties in their activities because of being in physical decline. The nation increased the existence value of the senior citizens by giving things(賜物) including chairs, rice, meat, and ice economically, exoneration(免罪), the reduction system, and wergild legally, and Noinjik called Gaja(加資) socially to them and changing them to the members of society. Yangnoyeon and Gaja held targeting people of every class by transcending position and official ranks make the point that the senior citizens who are more than 80 years old are subject to social jonno clear. That is, the senior citizens were subject to respect for the elderly as the persons who were socially respected transcending their position when they got to be 80 years old.