• Journal of Astronomy and Space Sciences
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• v.26 no.2
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• pp.229-236
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• 2009

KOorea Multi-purpose SATellite(KOMPSAT)-5 will be launched at 550km altitude in 2010. Accurate satellite position(20 cm) and velocity(0.03 cm/s) are required to treat highly precise Synthetic Aperture Radar(SAR) image processing. Ionosphere delay was eliminated using dual frequency GPS data and double differenced GPS measurement removed common clock errors of both GPS satellites and receiver. SAC-C carrier phase data with 0.1 Hz sampling rate was used to achieve precise orbit determination(POD) with ETRI GNSS Precise Orbit Determination(EGPOD) software, which was developed by ETRI. Dynamic model approach was used and satellite's position, velocity, and the coefficients of solar radiation pressure and drag were adjusted once per arc using Batch Least Square Estimator(BLSE) filter. Empirical accelerations for sinusoidal radial, along-track, and cross track terms were also estimated once per revolution for unmodeled dynamics. Additionally piece-wise constant acceleration for cross-track direction was estimated once per arc. The performance of POD was validated by comparing with JPL's Precise Orbit Ephemeris(POE).

• Korean Journal of Ecology and Environment
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• v.42 no.1
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• pp.124-133
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• 2009

Effects of substrates on the relative immigration activities (RIAs) of epilithic diatoms were examined in Sum River, a tributary of South Han River, Korea. Two hundreds of tile substrates coated with 5% agar were deposited at seven study stations (30 tiles per site) for one month from March 7 to April 7, 2008. Water sampling, physico-chemical factor measurement, and diatom analysis were performed in the field and laboratory. Over the study, major epilithic diatom species were Nitzschia amphibia, Navicula subminuscula, Cymbella minuta in both the natural and artificial substrates. Two dominant species, Nitzschia amphibia and Cymbella minuta often found at seven stations. Among all observed taxa, Nav. subminuscula and Caloneis silicula showed the highest RIA, with the value over 15 throughout the study. Regarding the algal morphology, the biraphe type species showed higher RIA than any other morph, while they comprised over 55% of total biomass, indicating a density effect. Additionally, a significant relationship between RIA and 20-day deposited substrate (p<0.05) showed in two diatom species, Nitzschia fonticola, Gomphonema quadripunctatum, which showed relatively high RIAs. These results indicate that the relative immigration activities of epilithic diatom species can be influenced by algal density in the water and substrate, nutrients, and deposited time at least 20 days.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.703-709
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• 2017

Korea Utility Helicopter(KUH) is a project to replace the aging helicopter presently being operated by the military with a domestic helicopter. The auxiliary power unit is a device that supplies emergency power to the system by an alternator installed when the main generator fails and the start motor converts the electrical energy of the battery into mechanical rotational energy to rotate the auxiliary power unit engine. With continuing power and operation, defects of the starting motor were found and improvements were carried out to solve it. In the failure mode analysis, the causes of possible defects were classified into 5 categories. Analysis of the 5 factors revealed that the main cause of defects is mechanical wear, which was found to be related to spring pressure. 250 tests were conducted through the theoretically determined pressure and regression analysis was performed with 4 sampling.The results showed that pressure was related to wear rate. In conclusion, early wear and breakage due to wear can be controlled through spring force and test showed the prediction of wear and the validity of the result were confirmed.

• Journal of Nutrition and Health
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• v.39 no.2
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• pp.160-170
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• 2006

This study was conducted to provide foundation data for making health care policy for married women by assessing the dietary intake between highly educated married, employed and unemployed women. It is a direct interview, cross-sectional study with 24-hour recall method for one day. In selecting the subjects for this study, married, unemployed women were selected from a certain area (Daedeok Science Town) in Daejeon where there are high rates of highly educated women, and the married, employed women were selected from the teaching profession in order to avoid confounding due to including a variety of jobs. According to the Korean Standard Classification of Occupations, teaching is the representational occupation of highly educated, married women. Then, to prevent confounding due to age, we selected the subjects out of each age group at the same rate through random sampling. Women who had not graduated college, worked only part-time, or had no current spouse were excluded. As a result, 486 highly-educated, married, unemployed (250) and employed (236) women were used for analyzing data. The unemployed women consumed a higher amount of fat, cholesterol, sodium, vitamin C and folic acid while the employed women consumed a higher amount of iron, vitamin $B_l$ and vitamin $B_2$. P/M/S ratio being 1/1.18/1.05 and 1/1.05/0.87, for the unemployed women and the employed women, respectively, unemployed respondents had a higher saturated fat intake than those of employed. It is in excess of the standard ratio (1/1/1) of the Korean RDA. At the same time, in unemployed respondents the percent of energy intake from fat (24.8%, 23.2%) and animal fat (12.4%, 11.4%) were higher than those of employed respondents. The mean daily nutrient intake of calcium, zinc, and iron for both groups of respondents were lower than the Korean RDA. Both groups had phosphorus as the highest nutrient and calcium as the lowest nutrient of INQ (Index of Nutritional Quality) while nutrients with the INQ being less than 1 were calcium and iron. To sum up, the following conclusions can be made: Nutrition education and guidance for reduction of the intake of fat, especially animal fat, are necessary for unemployed women. In addition, highly educated, married, unemployed and employed women should increase the consumption of foods rich in iron and calcium to prevent anemia and osteoporosis, while decreasing the intake of phosphorus to balance proportions of calcium and phosphorus.

• Journal of Nutrition and Health
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• v.15 no.3
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• pp.171-180
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• 1982

The nutritional survey and blood sampling was conducted from May 23 to 27, 1971, in order to investigate the state of the nutritional intake in relation to blood contents of rural women. This survey covered a total of 47 women residing in Youngam-gun, Cholla-namdo, Korea. The daily diet of these subjects was observed by 24-hour recall method and weighing method for 3 days and hemoglobin (Hb), hematocrit(Hct), mean corpuscular hemoglobin concentration (MCHC), serum protein, serum albumin, A/G ratio, serum iron, total iron binding capacity (TIBC), transferrin saturation (TS), serum cholesterol and blood specific gravity (SG) were measured. The results were summarized as follows ; The rate of intake of vegetable foods was high, especially cereals, and that of animal foods was low, especially eggs and milk and milk products. The daily intake of niacin was sufficient, and the intakes of energy and iron were also tend to be adequate. On the contrary, the intakes of vitamin A, $B_2$ and C, calcium and protein were insufficient. The mean red blood cell number was $410.8{\pm}26.4{\times}10^{4}/mm^{3},$ the mean values of Hb, Hct and MCHC were $12.5{\pm}0.9gm%$, $37.5{\pm}2.4%$ and $33.2{\pm}0.5%$ thus the anemic prevalences were 21.3%, 12.8% and 93.6% comparing with the anemic criteria of WHO. The levels of serum protein and serum albumin were $7.1{\pm}0.4gm\;%$ and $4.3{\pm}0.3gm\;%$so the A/G ratio was indicated $1.6{\pm}0.2.$. The levels of serum iron and TIBC were $91.9{\pm}27.5{\mu}g/100ml and $297.5{\pm}31.4{\mu}g/100ml,$ so TS was calculated $31.2{\pm}9.7\;%$. The mean value of SG was $1.044{\pm}0.002,$ and the level of serum cholesterol was $164.3{\pm}25.4mg/dl$. In the relation between each of bloood content, Hb showed positive correlation not only with Hct but also protein at the level of significance of 1 per cent and 5 per cent, and protein also showed a positive correlation with serum cholesterol at the 1 per cent level of significance. In the relation between the nutrient intake and blood contents, vitamin C intake showed a positive correlation with Hb, serum protein and serum iron at the level of significance of 1 per cent, iron intake also showed a positive correlation with serum iron and serum cholesterol at the same significant level, and protein intake showed a positive correlation with serum iron at the at the level of significance of 5 per cent.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.12
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• pp.5295-5302
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• 2016

Objectives: A physically active lifestyle is important for cancer survivors. Therefore, this study was conducted to 1) provide population-based estimates of the prevalence of physical activity and sitting time, and 2) their correlates in Korean cancer survivors. Materials and Methods: This study analyzed a cancer survivor subsample (N=1,482) from 2008-2013 Korea National Health and Nutrition Examination Survey (KNHANES), data selected with a complex sampling design. Overall and subgroup-specific prevalences of physical activity and sitting time were estimated. Correlates of moderate- to vigorous-intensity physical activity ( MVPA) and sitting time were tested using age-group-specific hierarchical multiple regression models. Results: Overall adherence rate to physical activity guidelines was 34.9% (95% CI=31.5-38.4). Age-group-specific adherence rates were 41.1% (95% CI=36.3-45.9) in adults (30-64 years old), and 25.3% (95% CI=21.0-25.3) in older adults (65 years or older). Adults spent 213.33 minutes (95% CI=172.4-254.3) per week on MVPA and 55.3 minutes (95% CI=36.4-64.6) on sitting time per day. In adults, sitting time was significantly associated with employed status (B=28.0, p=0.046), smoking (B=-47.4, p=0.020), and number of comorbidity conditions (B=-13, p=.037). MVPA was significantly associated with marital status (B=134.9, p<0.001), employment status (B=98.12, p=.046), and years since cancer diagnosis (B=104.7, p=0.015). Older adults spent 162.2 minutes (95% CI=119.5-204.8) per week on MVPA and 63.0 minutes (95% CI=45.0-89.5) on sitting time per day. Their significant correlates were sex (B= -45.2, p=0.014), smoking (B=-70.14, p<0.001), and years since cancer diagnosis (B=37.0, p=0.024). Age (B=5.8, p=0.042) and marital status (B=83.8, p=0.033) were also significantly associated with MVPA in older adults. Conclusion: A majority of Korean cancer survivors do not sufficiently participate in physical activity. In general, older, unhealthier, non-working, and being unmarried were risk factors for physical inactivity. While this study informs public health policy makers and practitioners about physical activity intervention demand for cancer survivors, future investigations should address psychosocial mediators to better inform intervention programs.

• Journal of the Korean Society of Child Welfare
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• no.54
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• pp.145-172
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• 2016

The purpose of this study was to examine whether parenting attitudes would have an effect on the developmental trajectories of school adjustment for adolescents in out-of-home care. Additionally, we hypothesized that this model would be different between boys and girls. In this study, we analyzed three waves of data collected from 341 adolescents living in residential facilities, group homes or foster homes by using cluster sampling methods. Growth-curve longitudinal analysis was conducted, and the results indicated that levels of school adjustment had increased from the 1st through the 3rd grade of middle school. Positive parenting attitudes had a positive impact on initial school adjustment and rate of change, whereas negative parenting attitudes had a negative impact only on the initial school adjustment. Second, multi-group analysis revealed that there were group differences between boys and girls in their initial school adjustment by positive parenting attitudes. Based on these results, this study discussed further suggestions to increase school adjustments for adolescents in out-of-home care.

• Journal of Korean Society of Forest Science
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• v.110 no.4
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• pp.543-553
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• 2021

This research focused on the investigation of isoprene and terpene emissions from 30 major urban tree species. We conducted sampling using a specific dynamic enclosure system between August and September 2020. Seedlings less than three years old were enclosed in a chamber consisting of a 400 L transparent Tedlar bag. The air-flows from the chamber's outlet were sampled using Tenax-filled sorbent tubes in the presence of standard conditions (temperature: 30℃, PAR: 1,000 μmol/m²/sec). A thermal desorption GC/MS system was used to analyze 38 BVOC compounds (isoprene, monoterpene, sesquiterpene, oxygenated monoterpene, and sesquiterpene). Isoprene emitters included Phyllostachys bambusoides, Quercus serrata, Daphniphyllum macropodum, and Buxus Koreana. Monoterpene emitters included Pinus rigida, Acer pictum subsp. mono, Larix kaempfer, Magnolia denudata, Metasequoia glyptostroboides, Pinus koraiensis, Pinus densiflora, and Abies holophylla. The monoterpene emission profiles were dominated by α-pinene, myrcene, limonene, β-pinen, and sabinene, while caryophyllene and farnesene were the prominent sesquiterpenes. Predominant oxygenated monoterpene compounds were also discovered as pulegone, borneol, menthol, eucalyptol, and nerol, while caryophyllene oxide were the prominent oxygenated sesquiterpenes. Sesquiterpenes and oxygenated sesquiterpenes had relatively lower contributions for all species.

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.5
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• pp.851-858
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• 2021

Due to the increase in renewable energy and distributed resources, not only traditional data but also various energy-related data are being generated in the new energy industry. In other words, there are various renewable energy facilities and power generation data, system operation data, metering and rate-related data, as well as weather and energy efficiency data necessary for new services and analysis. Energy big data processing technology can systematically analyze and diagnose data generated in the first half of the power production and consumption infrastructure, including distributed resources, systems, and AMI. Through this, it will be a technology that supports the creation of new businesses in convergence between the ICT industry and the energy industry. To this end, research on the data analysis system, such as itemized characteristic analysis of the collected data, correlation sampling, categorization of each feature, and element definition, is needed. In addition, research on data purification technology for data loss and abnormal state processing should be conducted. In addition, it is necessary to develop and structure NIFI, Spark, and HDFS systems so that energy data can be stored and managed in real time. In this study, the overall energy data processing technology and system for various power transactions as described above were proposed.

• Journal of the Korean Society of Radiology
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• v.15 no.2
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• pp.153-158
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• 2021

X-ray image analysis is a very important field to improve the early diagnosis rate and prediction accuracy of periodontal disease. Research on the development and application of artificial intelligence-based algorithms to improve the quality of such dental X-ray images is being widely conducted worldwide. Thus, the aim of this study was to design a super-resolution algorithm for predicting periodontal disease and to evaluate its applicability in dental X-ray images. The super-resolution algorithm was constructed based on the convolution layer and ReLU, and an image obtained by up-sampling a low-resolution image by 2 times was used as an input data. Also, 1,500 dental X-ray data used for deep learning training were used. Quantitative evaluation of images used root mean square error and structural similarity, which are factors that can measure similarity through comparison of two images. In addition, the recently developed no-reference based natural image quality evaluator and blind/referenceless image spatial quality evaluator were additionally analyzed. According to the results, we confirmed that the average similarity and no-reference-based evaluation values were improved by 1.86 and 2.14 times, respectively, compared to the existing bicubic-based upsampling method when the proposed method was used. In conclusion, the super-resolution algorithm for predicting periodontal disease proved useful in dental X-ray images, and it is expected to be highly applicable in various fields in the future.