• The Korean Journal of Nuclear Medicine Technology
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• v.18 no.2
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• pp.33-38
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• 2014

Purpose Auto exposure control (AEC) in SPECT/CT automatically controls the exposure dose (mA) according to patient's shape and size. The aim of this study was to evaluate the effect of AEC in SPECT/CT on exposure dose reduction and image quality. Materials and Methods The model of SPECT/CT used in this study was Discovery 670 (GE, USA), Smart mA for AEC; and $^{99m}Tc$ as a radioisotope. To compare SPECT and CT images by CT exposure dose variation, we used a standard technique set at 80, 100, 120, 140 kVp, 10, 30, 50, 100, 150, 200, 250 mA, and AEC at 80, 100, 120, 140 kVp, 10-250 mA. To evaluate resolution and contrast of SPECT images, triple line phantom and flangeless Esser PET phantom were used. For CT images, noise and uniformity were checked by anthropomrphic chest phantom. For dose evaluation to find DLP value, anthropomorphic chest phantom was used and the CT protocol of torso was applied by standard technique (120 kVp, 100 mA) and AEC (120 kVp, 10-250 mA). Results When standard and AEC were applied, the resolutions at SPECT images with attenuation correction (AC) were the same as FWHM by center 3.65 mm, left 3.48 mm, right 3.61 mm. Contrasts of standard and AEC showed no significant difference: standard 53.5, 29.8, 22.5, 15.8, 6.0, AEC 53.5, 29.6, 22.4, 15.7, 6.1 In CT images, noise values at standard and AEC were 15.4 and 18.5 respectively. The application of AEC increases noise but the value of coefficient variation were 33.8, 24.9 respectively, obtaining uniform noise image. The values of DLP at standard and AEC were 426.78 and 352.09 each, which shows that the application of AEC decreases exposure dose more than standard by approximately 18%. Conclusion The results of our study show that there was no difference of AC in SPECT images based on the CT exposure dose variation at SPECT/CT images. It was found that the increased CT exposure dose leads to the improvement of CT image quality but also increases the exposure dose. Thus, the use of AEC in SPECT/CT contributes to obtaining equal AC SPECT images, and uniform noise in CT images while reducing exposure dose.

• Journal of Veterinary Clinics
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• v.27 no.6
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• pp.647-651
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• 2010

The advantages of the $CO_2$ laser are offset by the delay in laser wound healing secondary to thermal damage. To minimize the undesirable thermal damage of the $CO_2$ laser, investigators have developed technical advances in the delivery system of the laser energy. This study compared tissue healing of the continuous and the pulsed modes $CO_2$ laser wounds in an animal surgery model. Five healthy Landrace and Yorkshire mixed breeds of both genders were used (45-51 kg, 4-6 months old, three males and two females). A full thickness wound of skin ($2{\times}2{\times}2cm^2$) was made over on the each pig's both sides of dorsal midline at 0, 7, 14, and 18 days. The wounds created at 18, 14, 7 and 0 days were named post-wounding day (PWD) 3, 7, 14 and 21, respectively. In each pig, one wound (left side) was treated pulsed $CO_2$ laser and the other wound (right side) was treated continuous wave $CO_2$ laser. Each wound was closed with two interrupted suture of 3-0 sutures. At 21 days after initial wounding, each wound was taken for histological evaluations. The degrees of reepithelialization were performed more prominently in the pulsed mode group than in the continuous mode group. The degrees of granulation were greater significantly in pulsed mode group than those in the continuous mode on PWD 3 (p < 0.05). The degrees of fibroblasts in the pulsed mode group were greater significantly in comparison to those in the continuous mode group on PWD 7, (p < 0.05). In conclusion, reepithelialization, granulation and fibroblasts in the pulsed mode group were greater markedly in comparison to those in the continuous mode group. It was considered that pulsed mode $CO_2$ laser was more suitable for the skin incision than the continuous mode $CO_2$ laser.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.8 no.4
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• pp.311-318
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• 2010

U. S. NRC Regulation Guide 1.52 regulating ESF ACS in nuclear power plants has been revised to revision 3. To apply reduction of operability test time, allowance of alternative challenge agents for in-place leak test of HEPA filters, and upgrade of Methyl Iodide penetration acceptance criterion in activated carbon performance test suggested in Reg. Guide 1.52(Rev.3) on Yonggwang units 5 and 6 ESF ACSes, technical feasibility study was carried out with on-site experiments as well as experiments with a lab-scale model. It was confirmed that the moisture in the system returned to the level before the test in 1 or 4 days even though the moisture was removed during the operability test lasting more than 10 hours. Therefore, it is appropriate to perform monthly operability test in 15 minutes just long enough to check the operability of equipment. To change challenge material for in-place HEPA filter leak test, size of aerosol, production rate, and leak detection capability were compared for DOP and PAO. It was concluded that PAO can be substituted for DOP in nuclear power plants. The upgrade of Methyl Iodide penetration acceptance criterion from 0.175 % to 0.5 % in active carbon filter bed deeper than 4 inches was to conform to the change of activated carbon performance test method to ASTM D3803(1989). It was confirmed that Methyl Iodide penetration acceptance criterion of 0.5 % under $30^{\circ}C$, relative humidity 95 % condition was conservatively good enough for testing performance of active carbon insitu. The licence change of Yonggwang units 5 and 6 has been completed based on this study.

• Journal of Korean Orthopaedic Sports Medicine
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• v.2 no.1
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• pp.28-36
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• 2003

Purpose: To determine and to compare the effects of cyclic loading on the fixation strength of different femoral fixation methods in ACL reconstruction. Materials and Methods: Biomechanical test using an Instron(R) machine (Model No.5569. Mass, U.S.A) were carried out to compare the pull out strength of six different femoral fixation techniques after a cyclic loading in 72 Yorkshire pig knees. The graft-bone complex was cyclically loaded between 30N and 150N at 50 mm/min rate for 1000 cycles and maximal tensile testing was performed. A preload of 30N was applied to the graft along the axis of the tunnel 15 minutes. ANOVA and the Duncan multiple comparison test was used for the statistical analysis. Results: The mean maximum tensile strength of femoral fixation before and after the cyclic loading test were 1003.4$\pm$145N and 601.1$\pm$154N in hamstring-LA screw(R) group, 595.5$\pm$104N and 360.7$\pm$56N in hamstring-Bioscrew(R) group, 1431.7$\pm$135N and 710.7$\pm$114N in hamstring-Semifix(R) group, 603.6$\pm$54N and 459.1$\pm$46N in hamstring-Endobutton(R) fixation group, 1067.4$\pm$145 and 601.8$\pm$134N in the BPTB-Titanium interference screw group, and 987.1$\pm$168N and 588.7$\pm$124N in the BPTB-Bioscrew(R) group. And these data illustrated that cyclic loading reduces the maximum tensile strength by 40 $\%$, 39 $\%$, 50 $\%$, 24 $\%$, 44 $\%$, 40 $\%$ respectively. Conclusions: With the results of these experiments it should be emphasized that rehabilitation exercises after anterior cruciate ligament reconstruction should be executed with precaution as the repetitive flexion and extension of the knee would compromise the maximum tensile strength of the graft tendon.

• Journal of Intelligence and Information Systems
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• v.21 no.2
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• pp.49-67
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• 2015

Recently, emerging the notion of big data and social media has led us to enter data's big bang. Social networking services are widely used by people around the world, and they have become a part of major communication tools for all ages. Over the last decade, as online social networking sites become increasingly popular, companies tend to focus on advanced social media analysis for their marketing strategies. In addition to social media analysis, companies are mainly concerned about propagating of negative opinions on social networking sites such as Facebook and Twitter, as well as e-commerce sites. The effect of online word of mouth (WOM) such as product rating, product review, and product recommendations is very influential, and negative opinions have significant impact on product sales. This trend has increased researchers' attention to a natural language processing, such as a sentiment analysis. A sentiment analysis, also refers to as an opinion mining, is a process of identifying the polarity of subjective information and has been applied to various research and practical fields. However, there are obstacles lies when Korean language (Hangul) is used in a natural language processing because it is an agglutinative language with rich morphology pose problems. Therefore, there is a lack of Korean natural language processing resources such as a sentiment lexicon, and this has resulted in significant limitations for researchers and practitioners who are considering sentiment analysis. Our study builds a Korean sentiment lexicon with collective intelligence, and provides API (Application Programming Interface) service to open and share a sentiment lexicon data with the public (www.openhangul.com). For the pre-processing, we have created a Korean lexicon database with over 517,178 words and classified them into sentiment and non-sentiment words. In order to classify them, we first identified stop words which often quite likely to play a negative role in sentiment analysis and excluded them from our sentiment scoring. In general, sentiment words are nouns, adjectives, verbs, adverbs as they have sentimental expressions such as positive, neutral, and negative. On the other hands, non-sentiment words are interjection, determiner, numeral, postposition, etc. as they generally have no sentimental expressions. To build a reliable sentiment lexicon, we have adopted a concept of collective intelligence as a model for crowdsourcing. In addition, a concept of folksonomy has been implemented in the process of taxonomy to help collective intelligence. In order to make up for an inherent weakness of folksonomy, we have adopted a majority rule by building a voting system. Participants, as voters were offered three voting options to choose from positivity, negativity, and neutrality, and the voting have been conducted on one of the largest social networking sites for college students in Korea. More than 35,000 votes have been made by college students in Korea, and we keep this voting system open by maintaining the project as a perpetual study. Besides, any change in the sentiment score of words can be an important observation because it enables us to keep track of temporal changes in Korean language as a natural language. Lastly, our study offers a RESTful, JSON based API service through a web platform to make easier support for users such as researchers, companies, and developers. Finally, our study makes important contributions to both research and practice. In terms of research, our Korean sentiment lexicon plays an important role as a resource for Korean natural language processing. In terms of practice, practitioners such as managers and marketers can implement sentiment analysis effectively by using Korean sentiment lexicon we built. Moreover, our study sheds new light on the value of folksonomy by combining collective intelligence, and we also expect to give a new direction and a new start to the development of Korean natural language processing.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.3
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• pp.253-261
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• 2005

Catalytic wet oxidation of ppm levels of trichloroethylene (TCE) in water has been conducted using $TiO_2$-supported cobalt oxides at a given temperature and weight hourly space velocity. 5% $CoO_x/TiO_2$ might be the most promising catalyst for the wet oxidation at $36^{\circ}C$ although it exhibited a transient behavior in time on-stream activity. Not only could the bare support be inactive for the wet decomposition reaction, but no TCE removal also occurred by the process of adsorption on $TiO_2$ surface. The catalytic activity was independent of all particle sizes used, thereby representing no mass transfer limitation in intraparticle diffusion. Characterization of the $CoO_x$ catalyst by acquiring XPS spectra of both fresh and used Co surfaces gave different surface spectral features of each $CoO_x$. Co $2p_{3/2}$ binding energy of Co species exposed predominantly onto the outermost surface of the fresh catalyst appeared at 781.3 eV, which is very similar to the chemical states of $CoTiO_x$ such as $Co_2TiO_4$ and $CoTiO_3$. The spent catalyst possessed a 780.3 eV main peak with a satellite structure at 795.8 eV. Based on XPS spectra of reference Co compound, the TCE-exposed Co surfaces could be assigned to be in the form of mainly $Co_3O_4$. XRD measurements indicated that the phase structure of Co species in 5% $CoO_x/TiO_2$ catalyst even before reaction is quite comparable to the diffraction lines of external $Co_3O_4$ standard. A model structure of $CoO_x$ present on titania surfaces would be $Co_3O_4$, encapsulated in thin-film $CoTiO_x$ species consisting of $Co_2TiO_4$ and $CoTiO_3$, which may be active for the decomposition of TCE in a flow of water.

• Journal of Korean Home Economics Education Association
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• v.32 no.2
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• pp.77-97
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• 2020

The purpose of this study was to develop and evaluate the sustainable housing teaching-learning process plan aimed to achieve the global SDGs through home economics class in middle school that is based on the ADDIE model. The overall objective of the plan was to contribute to cultivating students' sustainable housing values and to creating sustainable lifestyle through everyday practice. The plan consisting of 4 lessons contained various activity and visual resources(4 individual and 4 team activity sheets, 4 reading texts, 1 homework sheet and 1 evaluation sheet, and 7 videos) for students and (4 sets of ppt and 4 reading texts) for teachers. The theme and team activities of each lesson were related to 2~7 targets of 2~3 SDGs, in total 11 targets of 5 SDGs. The plan was implemented to 4 classes of 127 senior students at Y middle school in Cheongju city during the period from the 29^th of August to the 18^th of September, 2019. The results showed that students were very positive and highly satisfied with not only practical contents but also adequacy of resources and activities of the whole 4-lessons, so that they actively participated in the lessons more than usual and looked forward to learning more about it. They thoroughly enjoyed various team activities such as brain writing, mandal art, visual thinking, making UCC, and planning the sustainable village as well as writing a short reflective journal at the end of each lesson. Students also reported that they highly accomplished the goal of each lesson and the overall objective. It could be concluded that the teaching-learning process plan of 4-lessons could contribute to cultivating students' sustainable housing values and to creating sustainable lifestyle through practicing everyday life. It indicates that home economics is one of the major subjects to contribute to the attainment of global issue of SDGs for OECD education 2030 and to educate the practically acting global citizen.

• Culinary science and hospitality research
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• v.23 no.2
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• pp.64-73
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• 2017

Although 24-hour recalls (24HR) capture detailed information on a person's food intake, this method suffers from difficulties in adequately measuring the usual intake of foods that are not consumed daily by most. Therefore, the purpose of this study is to investigate whether frequency of Food Frequency Questionnaire (FFQ) can be utilized in form of covariate when calculating usual intake of episodically-consumed foods and their distributions. Data used in this study was from the Korean National Healthy and Nutrition Examination Survey (KNHANES) 2012~2014 (3 years) and 10,945 subjects participated in this survey who performed both of 24HR and FFQ. In order to analyze the data, amount of intake in each food, which was reported in 24HR was recalculated according to 112 items in FFQ. We first assessed the relationship between FFQ frequency and the amount reported on 24HR. Second, we assessed the relationship between usual portion size of FFQ and the amount reported on 24HR. Our hypothesis was that people who reported high FFQ-reported frequency or FFQ-reported usual portion size would consume larger amounts of that food on 24HR than those with lower frequency or portion size of consumption of a food on the FFQ. For 59 of 112 individual foods (52.2%), there were statistically significant increasing relationships between FFQ frequency and consumption-day intake. Also, 102 of 112 individual foods (90.3%), there were statistically significant increasing relationships between FFQ usual portion size and consumption-day intake. For 10 of 13 food groups (grains, fruits, eggs, pulses, root and tuber crops, milk products, meat, beverage, alcoholic drink, vegetable, seaweeds and others), there were statistically significant increasing relationships between FFQ frequency and consumption-day intake. And there were statistically significant increasing relationships between FFQ usual portion size and consumption-day intake for all food groups. This study confirmed consistent correlation between reported FFQ frequency or usual portion size of food (group) consumption and consumption-day intake on 24HR. Therefore the frequency data may be utilized as important covariate when estimating usual intake of food or food groups.

• KDI Journal of Economic Policy
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• v.30 no.1
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• pp.71-130
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• 2008

Using data from the Korean Labor & Income Panel Study (KLIPS), this study investigates private income transfers in Korea, where adult children have undertaken the most responsibility of supporting their elderly parents without well-established social safety net for the elderly. According to the KLIPS data, three out of five households provided some type of support for their aged parents and two out of five households of the elderly received financial support from their adult children on a regular base. However, the private income transfers in Korea are not enough to alleviate the impact of the fall in the earned income of those who retired and are approaching an age of needing financial assistance from external source. The monthly income of those at least the age of 75, even with the earning of their spouses, is below the staggering amount of 450,000 won, which indicates that the elderly in Korea are at high risk of poverty. In order to analyze microeconomic factors affecting the private income transfers to the elderly parents, the following three samples extracted from the KLIPS data are used: a sample of respondents of age 50 or older with detailed information on their financial status; a five-year household panel sample in which their unobserved family-specific and time-invariant characteristics can be controlled by the fixed-effects model; and a sample of the younger split-off household in which characteristics of both the elderly household and their adult children household can be controlled simultaneously. The results of estimating private income transfer models using these samples can be summarized as follows. First, the dominant motive lies on the children-to-parent altruistic relationship. Additionally, another is based on exchange motive, which is paid to the elderly parents who take care of their grandchildren. Second, the amount of private income transfers has negative correlation with the income of the elderly parents, while being positively correlated with the income of the adult children. However, its income elasticity is not that high. Third, the amount of private income transfers shows a pattern of reaching the highest level when the elderly parents are in the age of 75 years old, following a decreasing pattern thereafter. Fourth, public assistance, such as the National Basic Livelihood Security benefit, appears to crowd out private transfers. Private transfers have fared better than public transfers in alleviating elderly poverty, but the role of public transfers has been increasing rapidly since the welfare expansion after the financial crisis in the late 1990s, so that one of four elderly people depends on public transfers as their main income source in 2003. As of the same year, however, there existed and occupied 12% of the elderly households those who seemed eligible for the National Basic Livelihood benefit but did not receive any public assistance. To remove elderly poverty, government may need to improve welfare delivery system as well as to increase welfare budget for the poor. In the face of persistent elderly poverty and increasing demand for public support for the elderly, which will lead to increasing government debt, welfare policy needs targeting toward the neediest rather than expanding universal benefits that have less effect of income redistribution and heavier cost. Identifying every disadvantaged elderly in dire need for economic support and providing them with the basic livelihood security would be the most important and imminent responsibility that we all should assume to prepare for the growing aged population, and this also should accompany measures to utilize the elderly workforce with enough capability and strong will to work.

• Journal of Korean Society of Forest Science
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• v.67 no.1
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• pp.17-27
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• 1984

The Yangsan Forest Management Station (YFMS) of Korean German Forest Management Project (KGFMP), working with the 6 legal villages of Uljugun, Kyongnam, led the forest owners in the area to organize the Forest Management Cooperative (FMC) voluntairily for improvement of private forest management and fostered it as a model from May 1975 to Apr. 1984. YFMS sent out FMC a forest manager as a forestry expert carrying out the leading extension program at the equal position with forest owners and gave FMC financial, administrative and technical assitances. During the 6 years from 1977 to 1982, 4 FMC were founded and are being operated democratically. 228 forest owners have taken the membership of their own free will and the forestland of the members covers 2,567 ha equivalent to 57% of the total private forest in the area. During the period the total area of the planting and tending is 4,185 ha, this means that a member executed 3.1 ha of forest operations per year in average, showing the high willingness on forest operations. In addition the joint works have resulted in the joint properties equivalent to 27 million Won and it will be an important foundation for operation of FMC which is a forest owners's cooperative organization for improvement of private forest management in this area. The total expenditure spent for the fostering of FMC amounted to 497,587 thousand Won and 58% of them were charged from KGFMP funds, 27% from the forest owners and 15% from public funds. The expenditure for investment was 273,104 thousand Won and 59% of the sum were appropriated as subsidies at the national level. The forest owners charged 43% of that and this means that each member invested approximately 100 thousand Won to his forestland per year in average. For the extension program 169,503 thousand Won were spent and it can be explained that 5,885 Won were spent per ha a year. The organization of FMC operated autonomously in a democratic way and the horizontal and leading extension system, which aspects the human rights, were very much effective in fostering the cooperative organization of forest owners for improvement of private forest management.