• Journal of Oral Medicine and Pain
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• v.31 no.3
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• pp.245-254
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• 2006

While orofacial pain or various dental factors are generally considered as the primary cause of unilateral chewing tendency, there exist several studies indicating that dental factors did not affect the preferred chewing side. The aim of this study was to examine difference of occlusal scheme between the subjects with and without chewing side preference. The difference between the chewing and non-chewing sides in the unilateral chewing group was investigated as well. Computerized, T-Scan II system was used for occlusal analysis. 20 subjects for the unilateral chewing group (mean age of $25.25{\pm}2.84$ years) and 20 subjects for the bilateral chewing group (mean age of $27.00{\pm}5.07$ years) were selected by a questionnaire on presence or absence of chewing side preference and those with occlusal problem or pain and/or dysfunction of jaw were excluded. T-Scan recordings were obtained during maximum intercuspation and excursion movement. The number of contact points, relative occlusal force ratio between right and left sides, tooth sliding area and elapsed time throughout the maximum intercuspation were calculated. Elapsed time for excursion was also investigated. The results of this study shows that the unilateral chewing group had the smaller average tooth contact areas compared with those of the bilateral group (p<0.005). In the unilateral chewing group, the contact areas of non-chewing side are smaller than those of chewing side (p<0.005). The contact areas on their preferred sides were not significantly different with those of right or left side of the subjects without chewing side preference. There was no significant difference in the elapsed time during maximum intercuspation and lateral excursion, the sliding areas and relative of right-to-left occlusal force ratio between the two groups. From the results of this study, it is likely that individuals prefer chewing on the side with more contact areas for efficient chewing.

• Journal of Service Research and Studies
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• v.13 no.2
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• pp.41-61
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• 2023

The universal form of life in the era of the 4th industrial revolution can probably be summarized as the keyword "non-face-to-face". In particular, in terms of consumption activities, face-to-face contact is gradually changing to a system that minimizes, and offline stores are rapidly changing to non-contact services through kiosks and robots. The social structure is also changing with the passage of time, and most fundamentally, our dietary consumption patterns are changing. In particular, the increase in single-person households and the aging population are having a great impact on changes in the food service industry, which is closely related to dietary life. The HMR (Home Meal Replacement) market has grown significantly as the labor of cooking at home has decreased and the use of substitute foods has increased. As the size of the market has grown, the types of businesses that provide products have also diversified. The development of technology, non-face-to-face culture, and corporate management efficiency are intertwined, and unmanned stores are spreading recently. In this study, service quality attributes of HMR unmanned stores, where competition is gradually intensifying, are classified, and service quality classification using the Kano model and Timko's customer satisfaction coefficient are calculated to provide implications for service management based on customer satisfaction. As a result of the analysis, 'products with short cooking time' and 'variety of products (menu)' were classified as attractive qualities, and 'cleanliness inside/outside of the store' and 'products at reasonable prices' were classified as unified quality. In addition, 'convenience of self-checkout process' was classified as a natural quality, and 'convenience of in-store passage' was classified as an indifferent quality. Furthermore, when the service factor was satisfied within the HMR unmanned store, the factor with the highest satisfaction coefficient was 'product (menu) variety', and the factor with the highest dissatisfaction factor was 'convenience of self-checkout process'. Through the results of this study, it is intended to derive priorities in service quality management of HMR unmanned stores and provide strategic implications for related businesses.

• Journal of Life Science
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• v.33 no.2
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• pp.199-207
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• 2023

To prepare for the threat of a future epidemic in the post-COVID-19 era, research based on the one-health concept (i.e., the health of humans, animals, and the environment as "one") is essential. Cross-species infections are being identified as a result of the high infection rate and viral load of SARS-CoV-2 in humans. The possibility of transmission of SARS-CoV-2 from humans to mink has been determined. In addition, the transmission of SARS-CoV-2 from humans to cats through contact has been considered possible. The data so far show that livestock and poultry are less likely to be infected with SARS-CoV-2. However, if infections are established through a new mutation, the resulting diseases are expected to have enormous ripple effects on various fields, such as human food security, the economy, and trade. In addition, there are concerns about the endemic prospect of SARS-CoV-2 and the high accessibility of companion animals. This is because the evolution of the virus likely occurs in animal hosts. Once SARS-CoV-2 is established in other species, they might serve as intermediate hosts for the re-emergence of the virus in the human population. Thus, it is necessary to ensure a rapid response to future outbreaks by accumulating research data on the animal infection of SARS-CoV-2. These data can have implications for the development of animal models for vaccines and therapeutics against SARS-CoV-2. Therefore, in this study, epidemiological reviews were analyzed, and response strategies against SARS-CoV-2 infection in animals were presented using the One-health approach.

• Journal of Bio-Environment Control
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• v.28 no.4
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• pp.322-327
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• 2019

This study was conducted to improve the performance of automatic grafting robot using image recognition technique. The stem diameters of tomatoes and cucumber at the time of grafting were $2.5{\pm}0.3mm$ and $2.2{\pm}0.2mm$ for scions and $3.1{\pm}0.7mm$ and $3.6{\pm}0.3mm$ for rootstocks, respectively. The grafting failure was occurred when the different height between scions and rootstocks were over 4 mm and below 2 mm due to the small contact area of both cutting surface. Therefore, it was found that the height difference at the cutting surface of 3 mm is appropriate. This study also found that grafting failure was occurred when the stem diameters of both scions and rootstocks were thin. Therefore, it was suggested to use at least one stem with thicker than the average stem diameter. Field survey on the cutting angle of stems by hand were ranged from 13 to 55 degree for scions and 15 to 67 degree for rootstocks, respectively, which indicates that this could cause the grafting failure problem. However, the automatic grafting robot developed in this study rotates the seedlings 90 degree and then the stems are cut using a cutting blade. The control part of robot use all images taken from grafting process to determine the distance between a center of both ends of stem and a gripper center and then control the rotation angle of a gripper. Overall, this study found that The performance of automatic grafting robot using image recognition technique was superior with the grafting success rates of cucumber and tomato as $96{\pm}3.2%$ and $95{\pm}4%$, respectively.

• Economic and Environmental Geology
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• v.28 no.3
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• pp.185-197
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• 1995

Tungsten skarns in the Chungju mine which consists mainly of strata-bound type iron ore deposits are found in the vicinity of the contact between the age-unknown Kyemeongsan Formation and granitic rock intrusions of Mesozoic age($134{\pm}2Ma$). Tungsten skarns were formed extensively from alumina and silica-rich schistose rocks by the introduction of calcium and iron from hydrothermal solution. The skarns comprise a metasomatic column and are subdivided into four facies; garnet facies, wollastonite facies, epidote facies and chlorite facies. The skarn process in time-evolutional trend can be divided broadly into the four facies in terms of the paragenetic sequence of calc-silicates and their chemical composition. Skarn and ore minerals were formed in the following sequence; (1) garnet facies, adjacent to biotite granite, containing mainly garnet(>Ad96) and magnetite, (2) wollastonite facies containing mainly wollastonite and garnet(Ad95~60), (3) epidote facies, containing mainly epidote(Ps35~31), quartz, andradite-grossular(Ad63~50), and scheelite, (4) chlorite facies, adjacent to and replacing schist, containing mainly chrolite, muscovite, quartz, calcite, epidote(Ps31~25), hematite and sulfides. The mineral assemblage and mineral compositions. suggest that the chemical potentials of Ca and Fe increased toward the granitic rock, and the component Al, Mg, K, and Si decreased from the host rock to granitic rock. The homogenization temperature and salinity of fluid inclusion in scheelite, quartz and epidote of epidote facies skarn is $300-400^{\circ}C$ and 3-8wt.% eqiv. NaCl, respectively. ${\delta}^{34}S$ values of pyrite and galena associated with chlorite facies skarn is $9.13{\sim}9.51%_{\circ}$ and $5.85{\sim}5.96%_{\circ}$, respectively. The temperature obtained from isotopic com· position of coexisting pyrite-galena is $283{\pm}20^{\circ}C$. Mineral assemblages and fluid inclusion data indicate that skarn formed at low $X_{CO_2}$, approximately 0.01. Temperature of the skarn mineralization are estimated to be in the range of $400^{\circ}C$ to $260^{\circ}C$ and pressure to be 0.5 kbar. The oxygen fugacity($fo_2$) of the skarn mineralization decreased with time. The early skarn facies would have formed at log $fo_2$ values of about -25 to -27, and late skarn facies would have formed at log $fo_2$ values of -28 to -30. The estimated physicochemical condition during skarn formation suggests that the principal causes of scheelite mineralization are reduction of the ore·forming fluid and a decrease in temperature.

• The korean journal of orthodontics
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• v.38 no.6
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• pp.397-406
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• 2008

Objective: The purpose of this study was to provide clinical guidelines to indicate the best location for mini-implants as it relates to the cortical bone thickness and root proximity. Methods: CT images from 14 men and 14 women were used to evaluate the buccal interradicular cortical bone thickness and root proximity from mesial to the central incisor to the 2nd molar. Cortical bone thickness was measured at 4 different angles including $0^{\circ}$, $15^{\circ}$, $30^{\circ}$, and $45^{\circ}$. Results: There was a statistically significant difference in cortical bone thickness between the second premolar/first permanent molar site, central incisor/central incisor site, between the first/second permanent molar site and in the anterior region. A statistically significant difference in cortical bone thickness was also found when the angulation of placement was increased except for the 2 mm level from the alveolar crest. Interradicular spaces at the 1st/2nd premolar, 2nd premolar/1st permanent molar and 1st/2nd permanent molar sites are considered to be wide enough for mini-implant placement without root damage. Conclusions: Given the limits of this study, mini-implants for orthodontic anchorage may be well placed at the 4 and 6 mm level from the alveolar crest in the posterior region with a $30^{\circ}$ and $45^{\circ}$ angulation upon placement.

• Korean Chemical Engineering Research
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• v.52 no.5
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• pp.574-580
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• 2014

Storage tanks of Carbon dioxide ($CO_2$) carriers utilized for the purpose of carbon capture and storage (CCS) into subsea strata have to undergo a pre-cooling session before beginning to load cryogenic liquid cargos in order to prevent physical and thermal deterioration of tanks which may result from cryogenic $CO_2$ contacting tank walls directly. In this study we propose dynamic model to calculate the tank inflow of $CO_2$ gas injected for precooling process and its dynamic simulation results under proportional-integral control algorithm. We selected two cases in which each of them had one controlled variable (CV) as either the tank pressure or the tank temperature and discussed the results of that decision-making on the pre-cooling process. As a result we demonstrated that the controlling instability arising from nonlinearity and singularity of the mathematical model could be avoided by choosing tank pressure as CV instead of tank temperature.

• Journal of Astronomy and Space Sciences
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• v.10 no.2
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• pp.123-145
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• 1993

UBVRi photometry of Algol was carried out from December of 1988 to March of 1991 at Chungbuk National University Observatory and a total of 3465 observations in U, B, V, R, I were obtained. Three times of primary minimum light of JDH el 2447898.0938, JEH el 2448265.1205 and JDH el 2448288.0598, and two secondary minimum light of JDH el 2447808.1014 and JDH el 2448275.146 were determined from our observations. We analyzed simultaneously the UBVRI light curves of the Algol system with the Wilson-Devinney method for the determination of the photometric parameters. Indivisual masses for the 3 components of Algol are derived as $m_1$=3.36, $m_2$=0.76, $m_3$=1.6 in solar mass and radii as $R_1$=2.97, $R_2$=0.76 in solar radinus using i=$82.{\circ}47$, q=0.227, $r_1$=0.2102, $r_2$=0.2512 of our solution and some parameters of the spectroscopic solution of Hill et al. (1971). Our results is simiar to those reported by Kim (1989). The temperature of Algol C, $T_3$=8800 was obtained by means of fitting $l_1$, $l_2$, and $l_3$ of five colors to Planckian curve, and $R_3$=$1.6R_\odot$ is derived from its result. It is believed that its semidetached configuration of Algol A and B is the consequence of case B mass transfer. According to its location in a mass-radius diagram. Algol b may have evolved significantly in its Hburnning phase.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.4
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• pp.2310-2319
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• 2014

The study was to investigate the multicultural attitude of nursing students and non-nursing major students. And it was explored influencing factors related with it. This study was used a descriptive comparative designed. Data were collected 3 universities in D city in from Nov. to Dec. in 2012. After receiving the agreement, 309 nursing students and 195 non-nursing major students were recruited. They were asked to fill in a self-reported questionnaire about multicultural attitude. The Korean version Munroe Multicultural Attitude Scale Questionnaire (MASQUE) was used. Cronbach's alpha were .85. Data were analyzed by SPSS 18.0. The mean score of multicultural attitude was 4.44 of 6 points(73%) in all participants. Nursing students' multicultural attitudes scores were equal to other college students'. The factors related to multicultural attitude were the experiences of having foreigner friends, going abroad, attending multicultural events, and contacting multicultural contents. The students who have cared foreign patients were not higher than others in nursing students group(t=.30, p=.76). For nursing students contacting foreigners in clinical practice, it doesn't make a differnce in multicultural attitude. The culturally empowering programs were needed for nursing students to improve multicultural attitudes.

• The korean journal of orthodontics
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• v.35 no.1 s.108
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• pp.15-22
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• 2005

The Purpose of this study was to clarity morphological differences among mandibular dental arch forms in Korean malocclusion patients. The sample in this study consisted of 114 Class I. 119 Class II, and 135 Class III malocclusion cases. The most facial portions of 13 proximal contact areas were digitized from photocopied images of the mandibular dental arches. Clinical bracket points were calculated for each tooth based on the data on the mandibular tooth thickness. Four linear and two proportional measurements were undertaken The dental arches were classified into square. ovoid, and tapered forms to compare the frequency distributions. Our results suggested that there was no single arch form specific to any particular Angle classification or sex. It appeared to be the frequency of a particular arch form that varies among the Angle classifications. In comparison of arch measurements between male and female. there was no statistical difference except in the intermolar width. In comparison of arch size measurements among the different Angle classifications, there were statistically significant differences between Class I and Class III malocclusion groups and between Class II and Class III malocclusion groups. In comparison oi frequency distribution of arch forms in Class I and III malocclusion groups, the square form demonstrated the highest distribution followed by the ovoid and tapered forms in that order. In the Class II malocclusion group, the square form showed the highest distribution. followed by the tapered and ovoid forms in that order There was no statistical difference in the frequency distribution of arch forms between male and female groups.