• Journal of Technologic Dentistry
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• v.23 no.2
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• pp.17-47
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• 2002

The purpose of this study was to examine the 2001 curricula in 17 departments of dental technology across the nation in an attempt to find out the educational realities of the departments by term and school year and serve as a basis for the development of more advanced, efficient dental technology curriculum and common educational objectives. For that purpose, the 2001 curricula of the three-year dental laboratory technology departments were analyzed by school year and term to calculate the amount of required credit, the number of subjects, and the weekly classes for electives and major. The findings of this study could be listed as below: 1. The departments of dental laboratory technology nationwide investigated require students to get 120 to 135 credits in total. Out of the credits, 10 to 25 credits are assigned to the electives, and 106 to 11 8 credits are given to the major. 2. There are 50 to 68 subjects in the departments of dental technology. 5 to 16 subjects are the electives, and 41 to 59 are the major. 3. There are 150 to 196 classes per week, which consist of 10 to 30 ones for the electives and 137 to In for the major. 4. The curricula for the first semester of the first year are as follows: 1) 20 to 24 credits are required. 4 to 11 credits are alloted to the electives, and 9 to 19 credits are assigned to the major. 2) The number of subject is 9 to 13, which are composed of 2 to 7 for the electives and 4 to 9 for the major. 3) The weekly classes are 22 to 29. The classes for the electives range from 4 to 14 per week, and 10 to 20 classes a week are for the major. 5. The curricula for the second semester of the first year are as below: 1) There are 20 to 25 credits. 3 to 12 credits are assigned to the electives, and 12 to 19 credits are for the major. 2) The number of subject is 10 to 14, which consist of 2 to 6 for the electives and 6 to 10 for the major. 3) The weekly classes are 22 to 29. and 3 to 12 classes a week are for the electives, and 15 to 24 classes are for the major. 6. The curricula for the first semester of the second year are as below: 1) The number of credits ranges from 20 to 24. Only six colleges offer 2 credits for the electives and the major account for 18 to 24 ones. 2) There are 8 to 12 subjects. Only six colleges offer one or two electives, and 8 to 12 are the major. 3) The weekly classes are 23 to 33. Only six colleges offer 2 or 3 classes a week for the electives, and 21 to 33 classes are for the major. 7. The curricula for the second semester of the second year are as below: 1) The number of credits ranges from 19 to 24. Only two colleges offer 2 credits for the electives and the major account for 18 to 24 ones. 2) There are 7 to 12 subjects. Only two colleges offer one or two electives, and 8 to 12 are the major. 3) The weekly classes are 24 to 36. Only two colleges offer 2 classes a week for the electives, and 24 to 36 classes are for the major. 8. The curricula for the first semester Of the third year are as below: 1) There are 16 to 24 credits. Just a college assigns 2 credits to the electives, and 16 to 24 credits are given to the major. 2) The number of subject is 5 to 12. Only a college offers one elective for optional course, and 5 to 12 are the major. 3) The weekly classes range from 18 to 39. Just a college offer 2 classes a week for the electives, and 18 to 39 classes are for the major. 9. The curricula for the second semester of the third year are as below: 1) There are 16 to 23 credits. Just a college assigns 2 credits to the electives, and 16 to 23 credits are given to the major. 2) The number of subject is 5 to 12. Only a college offers one elective for optional course, and 5 to 12 are the major. 3) The weekly classes range from 18 to 39. Just a college offer 2 classes a week for the electives, and 18 to 39 classes are for the major.

• BMB Reports
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• v.37 no.2
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• pp.139-143
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• 2004

The antioxidant responsive element (ARE) is a cis-acting regulatory element of genes encoding phase II detoxification enzymes and antioxidant proteins, such as NAD(P)H: quinone oxidoreductase 1, glutathione S-transferases, and glutamate-cysteine ligase. Interestingly, it has been reported that Nrf2 (NF-E2-related factor 2) regulates a wide array of ARE-driven genes in various cell types. Nrf2 is a basic leucine zipper transcription factor, which was originally identified as a binding protein of locus control region of ss-globin gene. The DNA binding sequence of Nrf2 and ARE sequence are very similar, and many studies demonstrated that Nrf2 binds to the ARE sites leading to up-regulation of downstream genes. The function of Nrf2 and its downstream target genes suggests that the Nrf2-ARE pathway is important in the cellular antioxidant defense system. In support of this, many studies showed a critical role of Nrf2 in cellular protection and anti-carcinogenicity, implying that the Nrf2-ARE pathway may serve as a therapeutic target for neurodegenerative diseases and cancers, in which oxidative stress is closely implicated.

• Proceedings of the Ginseng society Conference
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• 2008.05a
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• pp.74-75
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• 2008

This study is for geochemical relationships between ginsengs and soils from three representative soil types from Keumsan, shale, phyllite and granite. For these study, ginsengs, with the field and weathered soils were collected from the three regions, and are analysed for the major and trace elements. In the weathered soils(avg.), the granite and phyllite areas are high in the most of elements while the shale area is low. In the correlation coefficients, negative correlations are shown in the $Al_2O_3$-MgO pair while positive correlations, are shown in the Ba-Sr, Zr, Sr-Zr and Cs-Ge pairs. In the field soils(avg.), the granite and phyllite areas are, generally, high in the most of elements while the shale area is low. In the shale area, the major elements are high in the 4 year soils, but low in the 2 year soils. The LFS(Ba, Sr, Cs) and transitional elements are high in the 2 year soils, but low in the 4 year soils. The HFS(Y, Zr) is high in the 4 year soils. In the correlation coefficients, most of the elements from the 4 year show positive relationships. Positive correlations are shown in the $Al_2O_3$-CaO, MnO-MgO, V-Tl, and Ba-Sr pairs in all localities. In the ginseng contents, clear chemical differences with the ages are shown in the shale and granite ares, but not clear in the phyllite area. In the shale area Mn, Mg, Ba, Sr, and Y contents, increase with ages but decrease in Al, Cs, Be and Cd. In the correlation coefficients, degrees of the correlations for the major elements become low with the ages. Positive correlations are shown in the Al-Mn, Ti, Mn-Ti, Mg-Ca, Ca-K, Ba-Cs, Y and Cs-Y pairs. Comparisons with ginsengs of the same ages from the different areas suggest that generally, the 2 years in the shale and 3 and 4 years in the granite area are distinctive. Relative ratios(granite/ shale area) of the ginsengs are below 1 in the major elements except Mn in the 2 year ginsengs and above 1 in the other elements except Mg and Na in the 4 year. Relative ratios(granite/ phyllite area) of the ginsengs are high in the 3 year from the phyllite area. In the relative ratios(weathered/field soils) of the soils, numbers of the elements showing the ratios of above 1 increase from the shale, to phyllite and granite in the case of the major elements, but decrease in the case of the trace elements. These results suggest that major elements are high in the granite while trace elements are high in the shale area. In the relative ratios between field soils and ginsengs(field soils/ginseng), the shale area, regardless of the ages, show differences of several hundred times in the $Al_2O_3$, $TiO_2$, Y and Tl, of several ten times in the MnO, MgO and Ba and of several times in the CaO contents. These results suggest that ginseng contents are significantly different from the field soils in the $Al_2O_3$, $TiO_2$, Y and Tl, but similar in the CaO contents. The phyllite area, regardless of the ages, show differences of several hundred times in the $Al_2O_3$, $TiO_2$, Y, Tl and Be, of several ten times in the MnO, MgO, $Na_2O$ and Ba, and of several times to ten times in the CaO, $K_2O$ and Sr contents. These results suggest that ginseng contents are significantly different from those of the field soils in the $Al_2O_3$, $TiO_2$, Y, Tl and Be, but similar in the CaO, $K_2O$ and Sr contents. The granite area, regardless of the ages, show differences of several hundred times in the $Al_2O_3$, $TiO_2$, Tl and Be, of several ten times in the Ba, and of several times to ten times in the MgO and CaO contents. Of the other elements, differences of several times to ten times are shown in the MnO, $K_2O$ and Sr contents. These results suggest that ginseng contents are significantly different from those of the field soils in the $Al_2O_3$, $TiO_2$, Tl and Be, but similar in the $K_2O$ and Sr contents. Comparisons among the different ages from the same area suggest that, in the case of shale area, differences of several hundred times in the $Al_2O_3$ and $TiO_2$, of the several ten times in the MnO, MgO and Ba and several times in the CaO and $K_2O$ are shown in the 2 year ginsengs. Differences of several hundred times in the $Al_2O_3$, $TiO_2$, Cs, Y, Tl and Be, of above several ten times in the MnO, MgO, $K_2O$ and Ba, and of several times in the CaO and Sr are shown in the 3 year ginsengs. Differences of several hundred to thousand times in the $Al_2O_3$, of above several hundred times in the $TiO_2$, Cs and Y, and of several ten times in the MnO, MgO, $K_2O$ and Ba, and of several times in the $Na_2O$ are shown in the 4 year ginsengs. These relationships suggest that, regardless of the localities in the shale area, $Al_2O_3$ contents of the soils show big differences from those of the ginsengs. Regardless of the ages of ginsengs, comparisons with the overall average contents of each area show differences of several hundred times in the $Al_2O_3$, $TiO_2$, Cs and Tl and of several ten times in the MnO. These overall relationships suggest that the $Al_2O_3$, $TiO_2$, Cs and Tl contents of the soils are higher than those of the ginsengs, show big differences between two and low different contents are found in the MnO. In detail, differences of several hundred times in the Y, and ten times in the MgO and Sr, and of several times in the CaO, $Na_2O$, $K_2O$ in the case of shale area, are shown. These results suggest that the soils are higher than the ginsengs in the Y and significantly differences in Y, and moderately differences in the MgO and Sr, and low differences in the CaO, $Na_2O$ and $K_2O$ are shown between soils and ginsengs.

• International Journal of Air-Conditioning and Refrigeration
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• v.16 no.4
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• pp.117-123
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• 2008

The present study is directed at flow and heat transfer of $CO_2$ and oil mixtures in a circular tube. PAG and POE oils are considered in this study. Flow characteristics of $CO_2$ and oil mixtures have been investigated by flow visualization. Pressure drop has been measured in the range of operating mass flow rate from 0.1 to 0.4 kg/min in a circular tube. Heat transfer characteristics of $CO_2$/oil mixtures have been investigated using a counterflow heat exchanger. In case of pure liquid $CO_2$ as well as $CO_2$ and POE mixtures, flow are seen to be uniform so that $CO_2$ and POE oil are still miscible even at flowing state. However, it is found that $CO_2$ and PAG are not miscible. Pressure drop of $CO_2$/PAG mixtures are much higher than that of $CO_2$/POE mixtures as well as pure $CO_2$ at a fixed mass flow rate. As the concentration of POE oil is increased from 0 to 5 wt%, pressure drop is increased. However, heat transfer rate and heat transfer coefficient of $CO_2$/POE mixtures are much higher than that of $CO_2$/PAG mixtures. The f-factor correlation and Nusselt number correlation for $CO_2$/POE oil mixtures are suggested in this paper.

• Journal of the Korean Ceramic Society
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• v.24 no.3
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• pp.277-281
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• 1987

The various contents of MgF2 from 0 to 12.5wt% are studied in the AlF3-(Mg＋Sr＋Ba)F2-P2O5 system for the effects of various properties in glasses and the atmosphere of melting was controlled by N2 and Ar gas respectively. Density, refractive index, infrared transmission, thermal conductivity and thermal expansion coefficient of glasses are determined. Density, refractive index and thermal conductivity are decreased, micro-hardness and thermal expansion coefficient are increased according to the increasing of MgF2 contents. Infrared transmittance decreases with increasing the MgF2 contents and it slightly dropped by air than N2 and Ar atmosphere. Other properties are not influenced by atmosphere control.

• Korean Journal of Microbiology
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• v.21 no.2
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• pp.95-102
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• 1983

The penicillin G acylase(pga) gene was cloned in the vector plasmid pKM $300(Ar^r,\;Tc^r,\;6.33kb)$ for the study of the structure and expression of the pga gene. This recombinant plasmid pPAKS-1 DNA(24.5 Kb) was cleaved into 2 fragments by restriction enzyme Eco R1.1fragment by BamH1, 4fragments by Hind III, and 2 fragments by Pst I. The pga gene was located on the Eco R1.Hind III-C fragement of pPAKS-1. The recombinant plasmids pPAKS-1 and pPAKS-2, in which the Hind III-B and Hind III-D fragments pPAKS-1 are deleted, are characterized. The results are summarized as follows : 1. Doubling times of bacterial strain bearing pPAKS-1 and pPAKS-2 are 90 and 60 minutes, respectively. 2. pPAKS-1 and pPAKS-2 are present at about 16-32 and 70 copies per cell, respectively, are 0.66 and 5.5 units, respectively, which represent 2-fold and 20-fold higher enzyme 4. pPAKS-1 is very unstable, but pPAKS-2 is stable.

• International Journal of Highway Engineering
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• v.15 no.5
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• pp.123-133
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• 2013

PURPOSES : The present paper is to compare vehicles' $CO_2$ emissions in roundabouts and signalized intersections. METHODS : The present paper uses the SIDRA software with variables of traffic and road conditions. RESULTS : The results of the study are as follows : First, when entering traffic volumes are more than 1600pcph, vehicle's $CO_2$ emissions in roundabouts are lower than those of signalized intersections regardless of the left turn ratio. Second, When entering traffic volumes are more than 2800pcph, vehicles's $CO_2$ emissions in 2-lane approaches are lower than those of 1-lane approaches in signalized intersection. Third, when entering traffic volumes are more than 1600pcph, vehicle's $CO_2$ emissions of CASE B are lowest. (CASE B is the condition with one exclusive left-turn lane and one exclusive straight lane and one shared straight lane with right-turn.) Also, CASE A is the condition that vehicle's $CO_2$ emissions in roundabouts are lower than those of signalized intersections between 1600pcph and 3600pcph. (CASE A is the condition with one exclusive left-turn lane and one shared straight lane with right-turn.) But, when entering traffic volumes are more than 4000pcph, vehicle's $CO_2$ emissions in signalized intersections is lower than those of roundabouts. CONCLUSIONS : It may be concluded that vehicle's $CO_2$ emissions on roundabouts are much lower than those of signalized intersections, especially, when entering traffics volumes are between 1600pcph and 3600pcph in 1-lane or 2-lane approaches.

• Journal of Chest Surgery
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• v.8 no.2
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• pp.81-88
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• 1975

Up to October 31, 1975, 34 cases of atrial septal defect, secundum type, operated in this department, were presented. This is 23.2% of all congenital heart diseases, operated utilizing cardiopulmonary bypass, in this department during this period [34 out of 146]. Out of 34 cases, 32 cases are pure ostium secundum type and one case is sinus venosus and another one is ostium secundum type with partial anomalous pulmonary venous drainage. Six cases of endocardial cushion defect and 3 cases of trilogy of Fallot are excluded in this report. All 34 cases are repaired under direct vision utilizing extracorporeal circulation. Among 34 cases of atrial septal defect, 16 cases are male, and 18 cases are female. Their ages range between 3 to 48 years, but over 59% of the cases are below the ages of 20 years. Thirty-two cases are repaired by direct sutures while 2 cases are repaired with Teflon patches. The average perfusion time is 30 minutes; the shortest 12 and the longest 81 minutes. The number of the defect is single in 31 cases, double in 2 cases, triple in one case. But the associated defect except the main defect are so small as can be closed by simple direct suture. The size of the defect is average $12cm^2$; the smallest 0.7 and the largest $25cm^2$. The surgical mortality is 2 cases [5.6%] and other cases are found to be excellent in the follow up studies.

• Journal of the Korean Geographical Society
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• v.39 no.3
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• pp.425-443
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• 2004

Fluvial terraces is poorly developed along Bukhan River in Central Korea. Altitude from riverbed of T1 terraces are 18-29m, T2 terraces 2539m, respectively. Rubification index of T2 is 0.66, T1 is 0.54, and thickness of gravel weathering rind on gneiss of T2 are 14.0mm, granites of T2 are $\infty$, gneiss of T1 are 5.0mm and granites of T2 are 8.0mm, because weathering in deposits of T2 terraces, older than T1, is severer than T1 terraces. Since deposits in T2 have more active and longer weathering than T1, SiO$_2$/Al$_2$O$_3$ is 3.32 in T2 and 4.06 in T1, and SiO$_2$/R$_2$O$_3$ is 2.64 in T2 and 3.19 in T1. CIA(Chemical Index of Alteration) is 87.85％ in T2 and 85.88％ in T1. Kaolinite and halloysite are founded in deposits of T2 indicating high weathering, and are founded gibbsite made tv eluviation of kaolinite. However, deposits of T1 have no kaolinite, and are found plagioclase, weak mineral in weathering process. Comparing to previous researches by estimated age as altitude from riverbed, rubification index, thickness of gravel weathering rind, element contents and mineral composition, forming age of T2 terraces in Bukhan River are estimated in marine oxygen isotope stage 6 (130-190ka), and T1 terraces are marine oxygen isotope stage 4(59-74ka).

• Bulletin of the Korean Chemical Society
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• v.34 no.7
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• pp.2167-2170
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• 2013

A low-cost and simple recycling process of waste thermoelectric modules has been investigated using chemical reduction methods. The recycling is separated by two processes, such as dissolving and reduction. When the waste thermoelectric chips are immersed into a high concentration of $HNO_3$ aqueous solution at $100^{\circ}C$, oxide powders, e.g., $TeO_2$ and $Sb_2O_3$, are precipitated in the $Bi^{3+}$ and $HTeO{_2}^+$ ions contained solution. By employing a reduction process with the ions contained solutions, $Bi_2Te_3$ nanoparticles are successfully synthesized. Due to high reduction potential of $HTeO{_2}^+$ to Te, Te elements are initially formed and subsequently $Bi_2Te_3$ nanoparticles are formed. The average particle size of $Bi_2Te_3$ was calculated to be 25 nm with homogeneous size distribution. On the other hand, when the precipitated powders reduced by hydrazine, $Sb_2O_3$ and Te nanoparticles are synthesized because of higher reduction potentials of $TeO_2$ to Te. After the washing step, the $Sb_2O_3$ are clearly removed, results in Te nanoparticles.