• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.6
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• pp.557-565
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• 1984

The year-to-year fluctuations of seasonal variation of sea surface temperatures (SST) in the Korea Strait are studied based on monthly SST data for more than 50 years at Mitsushima ana Okinoshima in the strait. The frequency distribution of SST has two peaks at temperatures below and above the multi-year average, but that of SST anomalies has only one peak at the zero anomaly. More than $95\%$ of the anomalies are in the range of ${\pm}2^{\circ}C$. The harmonic constansts of seasonal SST variation vary from year to year. The standard deviations of annual means, annual amplitudes, ana semi-annual amplitudes are less than $1^{\circ}C$, and those of the annual ana semi-annual phases are about $5^{\circ}$ and less than $50^{\circ}$, respectively. The SST in the Korea Strait have a tendency to decrease their amplitudes as the annual means increase. Physical mechanisms responsible for the analyzed results are discussed in this paper.

• Journal of the Speleological Society of Korea
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• v.14 no.15
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• pp.42-90
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• 1987

Lee, Moon Won reported by 63 kinds lescribing the petrography and bulk chemical Composition in Petrology of Cheju volcanic island. The total Chemical Composition data was analyzed by the program of FORTRAN77. First, the Conversition equations and the scatter diagram were examined to the analysis, by the least square method. Next, a statistical data requested a mean Value, maximum value, minimum value, the range, the standard deviation, the variance, the Standord Error and the Coefficient of variation. In the standard deviation, a small Composition is MnO and P$_2$O$\sub$5/, a large Composition is SiO$_2$, Mgo and FeO. The Standard error and the variance were the tandency looked like the Standard deviation well. However, the Coefficient Variation differs from the Standard deviation. Where, a large Coefficient of variation are H$_2$O$\^$-/ and H$_2$O$\^$+/, a small Coefficient of variation are Al$_2$O$_3$ and SiO$_2$. The Correlation of Coefficient Can be Calculated numerically from the relation between SiO$_2$, Al$_2$O$_3$ and TiO$_2$ to other Compositions.

• Journal of the Korean Chemical Society
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• v.47 no.6
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• pp.578-584
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• 2003

Polychlorinated biphenyls (PCBs) known as environmental contaminants in soil were analyzed by the soil pollution standard process test and the static supercritical $CO_2$ extraction mode. It was shown that the percent average recoveries of PCBs by the soil pollution standard process test were ranged in 25-35% and the corresponding standard deviations were above 10%. In contrast, the percent average recoveries of PCBs by the static supercritical $CO_2$ extraction mode were 2-2.5 times higher and standard deviations were within 7%. These results indicate that static supercritical $CO_2$ extraction mode may be a useful alternative to sample pretreatment certified by the soil pollution standard process test. The increasing supercritical $CO_2$ pressure from 1130 psi to 1996 psi at $40^{\circ}C$ enhanced the recovery of all PCB congeners from soil. However, at same Tc and Pc, the equilibrium time (5 versus 60 minutes) had no effect on the recovery of each PCB congener. Finally, similar PCB recoveries were obtained under the same extraction condition, regardless of the molecular weight and structure (coplanar versus non-coplanar) of PCB congeners.

• Journal of Nutrition and Health
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• v.9 no.2
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• pp.68-86
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• 1976

The primary purpose of this study is to evaluate the correct nutritional status on pre-school children in Korea. Furthermore, it made an attempt to find and define nutrional problems, and assist in establishment on their nutritional improvement plan. For this, food intake and health condition (physical, clinical, biochemical and parasitological) survey on 109 Pre-school children in both sexes, randomly selected from Yang-Gu area in Gang-Won province and Rea-ju area in Kyong-gy Province, were conducted by means of three-day records, during the two periods of Spring and Fall season in 1975. The results obtained are summerized as follows: 1. The food intake; Average food intake of the subjects per day were $508{\sim}647g$ ($83{\sim}91%$ in vegetable foods and $5.5{\sim}11.7%$ in animal foods) in Yang-gu area, and $587{\sim}698g$ ($88{\sim}89%$ in vegetable foods and $6.3{\sim}7.6%$ in animal foods) in Rea-ju area. 2. The intake of energy and nutrients; a) Calory intake. Average energy intake of subjects per day in Yang-gu area$(1120{\sim}1415kcal)$ were all lower than the Korean Recommended Dietary Allowances (RDA) in either Spring and Fall survey, whereas the subjects in Rea-ju area were lower intake $(1213{\sim}1418kcal)$ than the RDA in the Spring but higher intake$(1516{\sim}1755kcal)$ than the RDA in the Fall, and the average intake were similar level with that of RDA. b) Protein intake. Average protein intake of the subjects per day in Yang-gu area $(33{\sim}43g)$ girl subjects in Rea-ju area $(35{\sim}39g)$ were lower than the RDA in either Spring and Fall survey, whereas the boy subjects in Rea-ju area$(36{\sim}38g)$ were lower in Spring and higher $(49{\sim}57g)$ in the Fall than that of the RDA, but the average $(43{\sim}47g)$ were similar level with the RDA. The protein intake from animal sources in all subjects were much lower $(5.5{\sim}11.7\;of\;total\;protein)$ than the RDA. c) Fat intake. Average fat intake were very lower in all subjects of both area $(14{\sim}24g\;in\;Yang-gu,\;10{\sim}12g\;in\;Rea-ju)$ than that of RDA which is recommended $12{\sim}14%$ of total energy to be supplied from fat. d) Calcium intake. Average calcium intake were very low in all subjects of both area $(264{\sim}355mg\;in\;Yang-gu\;and\;283{\sim}429mg\;in\;Rea-ju)$, especially, these in Spring were about a half level of the RDA, and it was much increased in the Fall due to increased intake of milk, but it was still not enough than the RDA. e) Vitamin A intake. Average intake of V.A ($703{\sim}1465\;IU$ in Ynag-gu and $750{\sim}1521\;IU$ in Rea-ju) were also lower than the RDA, moreover their V-A sources were mainly vegetable, so that the V-A supply might be critical one for the subjected. f) Riboflavin intake. Average riboflavin intake on all subjects in both area except boys in Rea-ju area in Fall, were very lower than the RDA. 3. The physical status; a) Average weight and height of boys aged 4 and 5 in Yang-gu area and girls of aged 5 in Rea-ju area were lower than those of Korean Standard of 1967 report, but those by age of girls in Yang-gu area and boys in Rea-ju area were a little heigher than the Korean Standard. It is, hower, present Korean standard of physical status might be somehow heigher than the 1967, since the socio-economical situation has been much improved during past a decade. So that, if one considered on this sense, the physical status of the subjects on this survey might be somehow lower than those of present Korean standard. b) Average upper arm circumference in both area were no difference each other, and their mean values of age 4, 5 and 6 in boy and girl were 15.6, 16.5, 16.4 and 15.5, 16.5, 16.4cm respectively. c) Average chest girth of boys were similar to those of Korean standard whereas the girls were smaller than the Korea standard. The average head circumference also showed similar tendency with the chest girth. 4. The clinical findings; The most popular clinical signs were angular stomatitis and dental caries, and boys had more heigher incidence then the girls. 5. The biochemical findings; a) Hemoglobin and anemia Average Hb value of boys and girls were 11.4 and 10.9g per 100 ml of blood respectively. The incidence of anemia (Hb value below 11 g/100 ml, by WHO) was increased by age, and girls had more heigher incidence than the boy (34% : 48%). The incidence of anemia in age of 4,5, and 6 in boys and girls were 28%, 41% 34%, and 33%, 50%, 49% respectively. The degree of the anemia was not severe, and the anemia of there subjects may be caused mainly low intake of better quality protein and low iron intake as well. b) Hematocrit. Average Ht value of whole subject were $39.9{\sim}41.6%$. c) Blood plasma protein. Average blood plasma protein contents of whole subjects were $6.6{\sim}7.4gm$ per 100 ml. The incidence of deficient range (<6.0g%, by ICNND) was only one girl of age 4 in yang Gu area. 6. Parasitological findgs; The most popular parasitism were asicris lumbicoides and trichocephalus trichiura, and about 2/3 of the whole subjects were suffering one or more of these parasitism.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.2
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• pp.223-228
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• 2006

High-performance liquid chromatography(HPLC) and fluorescence derivatization were applied for a trace-level N-nitrosodimethylamine(NDMA) analysis of water samples. Fluorescence intensity was optimized with the excitation wavelength of 340 nm and the emission wavelength of 530 nm. pH adjustment after denitrosation was necessary to get a maximum intensity at pH between 9 and 12. Maximum intensity was found with a dansyl chloride concentration of 330 to 500 mg/L. Percentile error in the water sample analyses through solid phase extraction was 12-162% and 6-23% for the lower concentration level(10-200 ng/L NDMA) and the higher level(100-1000 ng/L NDMA), respectively, showing more discrepancy in lower level. However, the average ratios of estimated NDMA to the standard NDMA were close to 1 for both concentration ranges, presenting this HPLC method could detect from tens to hundreds nanograms NDMA per liter. Accurate determination of NDMA, which was injected to a wastewater effluent, revealed the selectivity of fluorescence derivatization for the target compound(NDMA) in the presence of complex interfering compounds. The HPLC with fluorescence derivatization may be applicable for determining NDMA of water and wastewater samples fur various research purposes.

• International Journal of Highway Engineering
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• v.8 no.4 s.30
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• pp.125-133
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• 2006

In this study, the Korean Industrial Standard(KS) penetration grade system was examined to evaluate its statistical validity. It was found from this limited study that the system has no gap between each grade, the binder falling out of limit trespasses into other binder grade. Therefore, many products can have similar property level with an adjacent grade even though the mean value is within the specification limit. It was also found out that the equal range setup of each grade, such as 20 for 40-60, 60-80, 80-100, has no statistical foundation. Since KS penetration grade is defined without gap between each grade, the producer must maintain the coefficient of variation below the level by the ASTM system to satisfy the normal quality control limit of products. Due to its lack of a gap between grades, higher percentage of products will be duplicated even if the mean is at the median of the specification limits due to material's quality uncertainty. Especially if the mean moves toward the upper limit, a half or more of the binder grade will be overlapped with the upper binder grade. Therefore, KS penetration specification should be immediately modified by statistically valid methodologies.

• Journal of Korean Orthopaedic Sports Medicine
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• v.7 no.1
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• pp.45-49
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• 2008

Purpose: To evaluate the recovery time of biochemical changes of body after half-course marathon running. Materials and methods: Thirteen amateur half course marathon runners (12 males and 1 females) were studied. Their average age was 44 years old (range: $38{\sim}54$). Biochemical parameters with blood test including AST, ALT, CK-MB, Treponin, BUN, Cr Na, K were evaluated at finish line, 2nd days, 2nd weeks after running. Results: All the biochemical changes were within normal range throughout recovery time, AST reached its maximum level at finish line and continued until 2nd day after running and returned its pre-running level at 2nd week's test. CK-MB reached its maximum level 2nd day after running and recovered at 2nd week's test. Na, K, BUN and Cr reached to the maximum level at finish line, and recovered to pre-running level at 2nd day's test. Conclusion: In case of half-course marathon, the changes of the kidney enzymes due to dehydration were recovered after 2nd day. And the biochemical indicators of muscle fatigue recovered after 2nd week. It needs at least 2 weeks rest after half-course marathon to recover all the biochemical parameter of the body.

• The Journal of the Korea Contents Association
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• v.11 no.7
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• pp.234-238
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• 2011

This paper will evaluate the usefulness of 3D target of CBCT by comparing human body's posture and position when simulated treatment is being carried out as well as human phantom posture and position using CBCT which is applying OBI. From the Rando Phantom which is located in the datum point moved in parallel and rotationary direction using CBCT. Then the mean and standard deviation difference on images location difference that are acquired were compared with real the Rando Phantom' moved distance. To make a plan of simulated treatment with the same procedure of real radiation therapy, we are going to setup the Rando Phantom. With an assumption that the position is set in accurate place, we measured the setup errors accroding to the change of the translation and rotation. Tests are repeated 10 times to get the standard deviation of the error values. The variability in couch shift after positioning equivalent to average residual error showed lateral $0.2{\pm}0.2$mm, longitudinal $0.4{\pm}0.3$mm, vertical $-0.4{\pm}0.1$mm. The average rotation erroes target localization after simulated $0.4{\pm}0.2$ mm, $0.3{\pm}0.3$ mm, and $0.3{\pm}0.4$ mm. The detection error by rotation is $0{\sim}0.6^{\circ}$ CBCT 3D/3D matching using the Rando Phantom minimized the errors by realizing accurate matching during simulated treatment and patient caring.

• Progress in Medical Physics
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• v.18 no.1
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• pp.48-54
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• 2007

This study is to develope a phantom for MOSFET (Metal Oxide Semiconductors Field Effect Transistors) dosimetry and compare the dosimetric properties of standard MOSFET and microMOSFET with the phantom. In this study, the developed phantom have two shape: one is the shape of semi-sphere with 10cm diameters and the other one is the flat slab of $30{\times}30cm$with 1 cm thickness. The slab phantom was used for calibration and characterization measurements of reproducibility, linearity and dose rate dependency. The semi-sphere phantom was used for angular and directional dependence on the types of MOSFETs. The measurements were conducted under $10{\times}10cm^2$ fields at 100cm SSD with 6MV photon of Clinac (21EX, Varian, USA). For calibration and reproducibility, five standard MOSFETS and microMOSFETs were repeatedly Irradiated by 200cGy five times. The average calibration factor was a range of $1.09{\pm}0.01{\sim}1.12{\pm}0.02mV/cGy$ for standard MOSFETS and $2.81{\pm}0.03{\sim}2.85{\pm}0.04 mV/cGy$ for microMOSFETs. The response of reproducibility in the two types of MOSFETS was found to be maximum 2% variation. Dose linearity was evaluated In the range of 5 to 600 cGy and showed good linear response with $R^2$ value of 0.997 and 0.999. The dose rate dependence of standard MOSFET and microMOSFET was within 1% for 200 cGy from 100 to 500MU/min. For linearity, reproducibility and calibration factor, two types of MOSFETS showed similar results. On the other hand, the standard MOSFET and microMOSFET were found to be remarkable difference in angular and directional dependence. The measured angular dependence of standard MOSFET and microMOSFET was also found to be the variation of 13%, 10% and standard deviation of ${\pm}4.4%,\;{\pm}2.1%$. The directional dependence was found to be the variation of 5%, 2% and standard deviation of ${\pm}2.1%,\;{\pm}1.5%$. Therefore, dose verification of radiation therapy used multidirectional X-ray beam treatments allows for better the use of microMOSFET which has a reduced angular and directional dependence than that of standard MOSFET.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.10 no.2
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• pp.57-62
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• 1992

As population is increased, land use types are changed mountainous areas from flatland in Korea. Because natural disaster as landslides occur of life, property, and environmental damage, prediction of landslides have become increasingly important. We focus on the issue for assessment of landslides, not slope stability analysis for a simple slope site. In this study, we could know the correlations of mean, standard deviation for brightness value of imagery by aerial photo scanning. The range of brightness values and standard deviation of landslide area is 35~65 and tend to increment of value, in the every years. When evaluating large regions with past occurrence of landslides, it is possible to search for correlation of site conditions such as degree of slope, soil characteristics, vegetative cover, and rainfall conditions in aerial photo interpretation data.