• Economic and Environmental Geology
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• v.49 no.4
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• pp.301-314
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• 2016

Disused Sealed Radioactive Sources (DSRSs) are stored temporally in the centralized storage facility of Korea Radioactive Waste Agency (KORAD) and planned to be disposed in the low- and intermediate-level radioactive waste (LILW) disposal facility in Gyeongju city. In this study, preliminary post-closure safety assessment was performed for DSRSs in order to draw up an optimum disposal plan. Two types of disposal options were considered, i.e. engineered vault type disposal and rock cavern type disposal which were planned to be constructed and operated respectively in LILW disposal facility in Gyeongju city. Assessment end-point was individual effective dose of critical group and calculated by using GoldSim code. In normal scenario, the maximum dose was estimated to be approximately $1{\times}10^{-7}mSv/yr$ for both disposal options. It meant that both options had sufficient safety margin when compared with regulatory limit (0.1 mSv/yr). Otherwise, in well scenario, the maximum dose exceeded regulatory limit of 1 mSv/yr in engineered vault type disposal and the exposure dose was mainly contributed by $^{226}Ra$, $^{210}Pb$ (daughter nuclide of $^{226}Ra$) and $^{237}Np$ (daughter nuclide of $^{241}Am$). For rock cavern type disposal, even though the peak dose satisfied regulatory limit, the exposure doses by $^{14}C$ and $^{237}Np$ were relatively high above 10% of regulatory limit. Therefore, it is necessary to exclude $^{14}C$, $^{226}Ra$ and $^{241}Am$ for two type of disposal options and additional management such as long-term storage and development of disposal container for those radionuclides should be performed before permanent disposal for conservative safety and security.

• Horticultural Science & Technology
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• v.32 no.3
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• pp.310-317
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• 2014

This study was conducted to find basic information for the research of morphological dormancy in seeds of two genera (Heloniopsis and Thalictrum) native to Korea. Seeds of Heloniopsis koreana, Heloniopsis tubiflora, Thalictrum rochenbrunianum, Thalictrum uchiyamai, and Thalictrum coreanum were collected, and embryo morphology and seed germination were investigated. All seeds of five species had underdeveloped embryos which occupied about 10-20% of the full seed length at maturity. The seeds of H. koreana and H. tubiflora had rudimentary embryos. The seeds of T. rochenbrunianum, T. uchiyamai, and T. coreanum had intermediate type between rudimentary and linear embryo. The small embryos of all seeds of five species grew to a critical length before radicles emerge from the seeds. At 30 days after sowing, the seeds of H. koreana and H. tubiflora germinated to 22.7% and 40.7%, respectively. On the other hand, the seeds of T. rochenbrunianum, T. uchiyamai, and T. coreanum germinated to 12.5%, 3.3%, and 0%, respectively. If embryo growth and germination in seeds are completed in approximately 30 days, the seed are said to have morphological dormancy (MD). However, if the seeds require > 30 days for germination, they are considered to have morphophysiological dormancy (MPD). Thus, the seeds of H. koreana and H. tubiflora had about 78% and 60% MPD, respectively. On the other hand, the seeds of T. rochenbrunianum, T. uchiyamai, amd T. coreanum had about 87%, 96%, and 100% MPD, respectively. There was a different level of dormancy (MD and MPD) within the same seed population examined. Therefore, germination of the seeds was delayed due to the underdeveloped embryos. This result could contribute to determine morphological seed dormancy and germination mechanism in seeds of the Korean Peninsula.

• Food Science and Preservation
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• v.15 no.1
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• pp.118-124
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• 2008

The chemical compositions and antioxidant activities of four different colored rice cultivars (white-colored rice: WCR, brown-colored rice: BCR, brown-colored waxy rice: BCWR, black-colored rice: BKCR) were investigated to evaluate the quality characteristics of the new brown rice cultivars. There was no significant differences in chemical compositions amongst the four rice cultivars, although WCR had higher amount of carbohydrate than did the other rice cultivars. 'The major fatty acids in the four rice cultivars were linoleic, oleic and palmitic acids, which accounted for about 96% of total fatty acids. Of note, higher amounts of saturated fatty acids (24.8%) and lower amount of unsaturated fatty acids (75.2%) were observed in BKCR than in the other rice cultivars. Two brown-colored rice cultivars, BCR and BCWR, possessed higher amounts of linoleic acid (40.8% and 42.1%, respectively) than did the other cultivars. The highest level of ${\alpha}$-tocopherol was found in WCR (51.3mg%), followed by BKCR (38.6mg%), BCWR (37.2 mg%), and BCR (34.5mg%). Free amino acid analysis showed that aspartic and glutamic acids were major amino acids of all cultivars, whereas phenylalanine, lysine, and histidine were minor. Particularly, relatively higher contents of aspartic and glutamic acids were found in BKCR, while relatively higher levels of alanine and ${\gamma}$-aminobutyric acid (GABA) were observed in BCR and BCWR. Also, BKCR had the highest phenolic content and antioxidant activity of any cultivar, followed by the two brown-colored rice cultivars and WCR. These results suggested that the new brown rice cultivars may possess quality characteristics intermediate between those of WCR and BCR.

• Journal of Korean society of Dental Hygiene
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• v.6 no.4
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• pp.437-453
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• 2006

To analyze dental hygienists and other manpower at dental care service institutions where a dental coordinator was working among about 200 dental care service institutions in Seoul, Gyeonggi Province, and Incheon as of June 2005 for contents of training for dental coordinators, opinions of qualification of dental coordinators, present and future services provided by dental coordinators, and awareness of dental coordinators and to provide basic data about future services, roles, and cultivation of dental coordinators, a survey was conducted and 216 copies returned were analyzed, obtaining the following results. 1. 83.8 percent needed an educational program for dental coordinators as an educational content; 41.7% had awareness of the educational content; and 83.8 percent insisted that over the intermediate level of curricula should be taken. Dental coordinator cultivation institutions identified included the institution under the control of the Korean Dental Hygienists Association and the education center for the department of dental hygiene; 76.9% insisted that an appropriate qualifying examination should be necessary. They suggested the central government department and the local government as a certification institution; 39.4% insisted that financial support for the education should be provided by financing education alone. Only 28.7% experienced dental coordinator education and 73.1% hoped to serve as a dental coordinator. They were found to expect a rise in payment(64.4%) and in the title(46.8%) after completion of the educational program. 2. 66.2% saw a dental hygienist as the most appropriate for a dental coordinator; clinical career (39.4%) and practical capacity(29.2%) were suggested as requirements for a dental coordinator; and a period of over three years(47.2%) was suggested for appropriate dental career. 3. Dental coordinators' present services included 'reservation management' for customer management, 'staff service training' for organization management, 'understanding of customer reception attitudes and actions' for self-management, 'hospital information management' for hospital marketing, 'acceptance' for hospital affairs management, and 'hospital environment management' for hospital facilities management; their future services included 'acquisition of ability to use a foreign language' for self-management, followed by 'staff service training' for organization management, 'training and counseling' for customer management, 'acquisition of counseling capacity' for self-management, 'complaining customer reception' for customer management, and 'marketing strategy implementation' for hospital marketing. 4. After comparing dental hygienists and other manpower in terms of dental coordinators' future services, dental hygienists showed interest in 'acquisition of ability to use a foreign language,' 'staff service training,' 'complaining customer reception,' and 'acquisition of counseling capacity' while other manpower showed interest in 'acquisition of ability to use a foreign language,' 'document data management,' 'acquisition of basic service manner,' 'acquisition of counseling capacity,' 'manpower management,' 'establishment and evaluation of a marketing strategy,' and 'education and counseling.' 5. As for awareness of dental coordinators, they were thought of as helpful in improving image of a dental clinic; it was found that continuous training should be necessary to develop dental coordinators' capacity; dental coordinators' services should be important and contribute to patients' qualitative satisfaction.

• Journal of the Korean Society of Radiology
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• v.15 no.5
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• pp.675-681
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• 2021

Recently, the Ministry of Education stipulates in the distance class operation regulations that student lecture evaluations for distance learning subjects should be conducted at least twice per semester and the results should be disclosed to students. Therefore, the lecture evaluation of D college was compared with the first semester of 2020 and the first semester of 2021. As for the multiple-choice evaluation result of the distance learning mid-course evaluation, the overall average of the mid-course evaluation of the distance class in the first semester of 2020 increased from 4.1819 to 4.4000 in the mid-course evaluation in the first semester of 2021.In the case of the first semester of 2020, due to Corona 19, all non-face-to-face classes were held, but in the first semester of 2021, face-to-face classes increased. The overall satisfaction level rose from 4.18 points in the first semester of 2020 to 4.39 points in the first semester of 2021. The screen composition, sound and picture quality, playback time, face appearance, lecture material provision, and frequency of use of the top 3% and bottom 3% also increased. Despite the changes caused by the LMS replacement, which was a concern, student attendance, assignments, and test submission rates also increased compared to the previous year. The null hypothesis that 'the difference between the two scores is the same' is the null hypothesis because the probability of significance is 0.000 and less than 0.05 in the case of the best 3% of the test result of the test result of the mid-course evaluation of distance classes in the first semester of 2020 and the evaluation of the intermediate lectures in the first semester of 2021. As this was rejected, it can be seen that the best score for the 2021 school year has significantly increased compared to the first semester of 2020. Also, in the case of Worst 3% or less, the significance probability is 0.000, which is less than 0.05, so the null hypothesis that 'the difference between the two scores is the same' was rejected, indicating that the Worst score for the 2021 school year was significantly higher than that for the first semester of 2020.

• Korea Trade Review
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• v.42 no.5
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• pp.137-159
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• 2017

This study divides manufacturing in 18 countries including Korea, China, Japan and OECD countries into 11 areas and estimates and compares the technological efficiency of each industry. The traditional view of productivity is to increase production capacity through technological innovation or process innovation, but it is also influenced by the technological efficiency of production process. A Stochastic Frontier Production Model (SFM) is a representative method for estimating the technical efficiency of such production. First, as a result of estimating the production function by setting the output variable as total output or value-added, in both cases, the output increased significantly in all manufacturing sectors as inputs of labor, capital, and intermediate increased. On the other hand, R&D investment has a large impact on output in chemical, electronics, and machinery industries. Next, as a result of estimating the technological efficiency through the production function, when the total output is set as the output variable, the overall average of each sector is 0.8 or more, showing mostly high efficiency. However, when value-added was set, Japan had the highest level in most manufacturing sectors, while other countries were lower than the efficiency of the total output. Comparing the three countries of Korea, China and Japan, Japan showed the highest efficiency in most manufacturing sectors, and Korea was about half or one third of Japan and China was lower than Korea. However, in the food and electronics sectors, China is higher than Korea, indicating that China's production efficiency has greatly improved. As such, Korea is not able to narrow its gap with Japan relatively faster than China's rapid growth. Therefore, various policy supports are needed to promote technology development. In addition, in order to improve manufacturing productivity, it is necessary to shift to an economic structure that can raise technological efficiency as well as technology development.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.21 no.2
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• pp.281-313
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• 1976

To obtain fundamental informations on cotton breeding efficiences for Korea, individual genetic relationships and interrelationships between the agronomic characteristics of Upland cotton were investigated. These experiments were couducted at the Mokpo Branch Station $(34^{\circ}48'N, $ $126^{\circ}23'E$ and altitude of 10m above sea level) from 1969 through 1972. Heterosis, combining ability, dominance and recessive gene action, genetic variance, and phenotypic and genotypic correlation were investigated by $F_1'S$ from an 11-parent partial diallel cross and the segregating $F_2$ and $F_3$ populations of the cross Paymaster times Heujueusseo Trice. The following points resulted from this study, 1. Heteroses for number of bolls per plant and lint yield were significant at 27, 84% and 37.26%, respectively. No other character had significant heteroses. 2. The GCA estimates for all studied characteristics were higher than the SCA estimates. Varieties with high GCA effects were Suwon 1 for earliness, Paymaster and Arijona for high lint percent, and Arijona for long fiber, etc, 3. SCA estimates for lint yield varied widely in crosses with Mokpo 4, Mokpo 6 and Heujueusseo Trice. Those crosses with the highest SCA effects were combinations with large characteristics differences, Example of these crosses are Mokpo 4 times Acala 1517W, Mokpo 4 times D. P. L. and Heujueusseo Trice aud Paymaster. 4. Early-maturing varieties were completely dominant to late-maturing varieties in some combinations while other crosses gave intermediate phenotypes. These results suggest additive genetic action by multi-genes. Heujueusseo Trice, Mokpo 6, and Suwon 1 showed highest degree of dominance for earliness. 5. There were no significant trends for inheritance of weight of boll and 100 seeds weight. 6. Long staple was partially to completely dominant to short staple. Though there were single gene ratios the rate of dominance decreased in the $F_2$ and $F_3$ populations in the cross between the long staple variety Paymaster and the short staple variety Heujueusseo Trice. Diallel cross $F_1$ hybrids showed complicated allelic gene action for staple length. Various dominance degree were shown by varieties. 7. Number of bolls per plant indicated strong over-dominance and small non-allelic additive gene action. 8. Lint Yield was characterized by over-dominance and by multiple non-allelic-gene action. High-yielding varieties were dominant to low-yielding ones. However, the low-yielding variety Heujueusseo Trice showed over-dominance, indicating different reactions according to the varieties and combinations. 9. Broad sense heritability for days to flowering was 34-39% while narrow sense heritability was 11%. Large variations of individual plants caused by Korean climatic conditions cause this situation. Heritability estimates for weight of boll was 30% for broad sense and 22% for narrow sense. 10. Heritability estimates for staple length and lint percent were very high suggesting strong selection effects. 11. Narrow sense heritability estimates for number of bolls per plant was 30% in the diallel cross $F_1$ hybrids and 36% in the $F_2$ population of the special cross. Broad sense heritability was estimated at 67% suggesting that. 12. Heritability estimates for lint yield was low due to high over-dominance in the diallel cross $F_1$ hybrids. Heritability estimates for yield was low in the $F_1$ hybrids but high in the $F_2$ and $F_3$ populations. 13. Phenotypic and genotypic correlations between lint percent and days to flowering and between staple length and days to flowering were high in the $F_1, $ $F_2$ and $F_3$ populations. Late-maturing varieties and individuals had long staple and high lint percent in general. As the correlation between days to flowering and lint yield was extremely low, the two traits were considered independent of each other. Days to flowering and number of bolls per plant were negatively correlated in the $F_3$ population, indicating early-maturing individual plants with many bolls may be readily selected. 14. Phenotypic and genotypic correlations between lint percent and staple length were high in $F_1, $ $F_2$ and $F_3$ populations. Accordingly, long staple varieties were high in lint percent. It was recognized that lint yield and lint percent were positively correlated in the diallel cross $F_1$ hybrids, and lint percent and staple length were positively correlated in the $F_2$ population, indicating that lint percent and staple length affect lint yield. 15. Lint yield was significantly and positively phenotypically correlated with number of bolls per plant in $F_1, $ $F_2$ and $F_3$ populations. A high genotypic correlation was also noted indicating a close genetic relationship. The selection efficiencies for a high-yielding variety can be increased when individual plants with many bolls are selected in later generations. The selection efficiencies for good fiber quality can be enhanced when individuals with long staple and high lint percent are selected in early generations.

• Radiation Oncology Journal
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• v.25 no.1
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• pp.16-25
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• 2007

[ $\underline{Purpose}$ ]: Breast conserving surgery (BCS) followed by chemotherapy (CTx.) and radiation therapy (RT) is widely performed for the treatment of early breast cancer. This retrospective study was undertaken to evaluate our interim results in terms of failure patterns, survival and relative risk factors. $\underline{Materials\;and\;Methods}$: From January 1999 through December 2003, 129 patients diagnosed with invasive breast cancer and treated with BCS followed by RT were subject to retrospective review. The median age of the patients was 45 years (age distribution, $27{\sim}76$ years). The proportions of patients according to their tumor, nodes, and metastases (TNM) stage were 65 (50.4%) in stage I, 41 (31.7%) in stage IIa, 13 (10.1%) in stage IIb, 9 (7.0%) in stage III, and 1 patient (0.8%) in stage IIIc. For 32 patients (24.8%), axillary node metastasis was found after dissection. BCS consisted of quadrantectomy in 115 patients (89.1%) and lumpectomy in 14 patients (10.6%). Axillary node dissection at axillary level I and II was performed for 120 patients (93%). For 7 patients (5.4%), only sentinel node dissection was performed with BCS. For 2 patients (1.6%) axillary dissection of any type was not performed. Postoperative RT was given with 6 MV X-rays. A tumor dose of 50.4 Gy was delivered to the entire breast area using a tangential field with a wedge compensator. An aditional dose of $9{\sim}16\;Gy$ was given to the primary tumor bed areas with electron beams. In 30 patients (23.3%), RT was delivered to the supraclavicular node. Most patients had adjuvant CTx. with $4{\sim}6$ cycles of CMF (cyclophosphamide, methotrexate, 5-fluorouracil) regimens. The median follow-up period was 50 months (range: $17{\sim}93$ months). $\underline{Results}$: The actuarial 5 year survival rate (5Y-OSR) was 96.9%, and the 5 year disease free survival rate (5Y-DFSR) was 93.7%. Local recurrences were noted in 2 patients (true: 2, regional node: 1) as the first sign of recurrence at a mean time of 29.3 months after surgery. Five patients developed distant metastases as the first sign of recurrence at $6{\sim}33$ months (mean 21 months). Sites of distant metastatic sites were bone in 3 patients, liver in 1 patient and systemic lesions in 1 patient. Among the patients with distant metastatic sites, two patients died at 17 and 25 months during the follow-up period. According to stage, the 5Y-OSR was 95.5%, 100%, 84.6%, and 100% for stage I, IIa, IIb, and III respectively. The 5Y-DFSR was 96.8%, 92.7%, 76.9%, and 100% for stage I, IIa, IIb, and III respectively. Stage was the only risk factor for local recurrence based on univariate analysis. Ten stage III patients included in this analysis had a primary tumor size of less than 3 cm and had more than 4 axillary lymph node metastases. The 10 stage III patients received not only breast RT but also received posterior axillary boost RT to the supraclavicular node. During the median 53.3 months follow-up period, no any local or distant failure was found. Complications were asymptomatic radiation pneumonitis in 10 patients, symptomatic pneumonitis in 1 patient and lymphedema in 8 patients. $\underline{Conclusion}$: Although our follow up period is short, we had excellent local control and survival results and reaffirmed that BCS followed by RT and CTx. appears to be an adequate treatment method. These results also provide evidence that distant failure occurs earlier and more frequent as compared with local failure. Further studies and a longer follow-up period are needed to assess the effectiveness of BCS followed by RT for the patients with less than a 3 cm primary tumor and more than 4 axillary node metastases.