• Korean Journal of Environment and Ecology
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• v.32 no.5
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• pp.486-496
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• 2018

In this study, we have selected Larix kaempferi as a study area in Woraksan National Park for understanding the ion index according to the difference of topography in national parks. We measured the weather and ion at two fixed points, ridge and valley, where the Larix kaempferi dominates in the same ecological structure in Woraksan National Park. The weather measurement results showed the average, maximum, and minimum temperatures of $28.22^{\circ}C$, $29.9^{\circ}C$, and $26.4^{\circ}C$, respectively at the ridge. The average, maximum, and minimum temperatures at the valley were $27.08^{\circ}C$, $27.8^{\circ}C$, and $25.5^{\circ}C$, respectively. The average, maximum, and minimum relatively humidities at the ridge were 67.02%, 75.25%, and 61.95%, respectively. he average, maximum, and minimum relatively humidities at the valley were 69.74%, 76.8%, and 63.75%, respectively. The average, maximum, and minimum amounts of positive ions generated in the ridge was $698.40{\pm}59.80ea/cm^3$, $885.88ea/cm^3$, and $597.88ea/cm^3$, respectively. The average, maximum, and minimum amounts of negative ions generated in the ridge were $736.07{\pm}83.89ea/cm^3$, $934.53ea/cm^3$, and $599.32ea/cm^3$, respectively. The ion index is calculated to be 1.06. The average, maximum, and minimum amounts of positive ions generated in the valley were $1,732.49{\pm}354.08ea/cm^3$, $2,652.10ea/cm^3$, and $1,110.92ea/cm^3$, respectively. The average, maximum, and minimum amounts of negative ions generated in the valley were $1,990.47{\pm}433.57ea/cm^3$, $3,126.75ea/cm^3$, and the minimum value was $1,352.17ea/cm^3$. The ion index is calculated to be 1.16. The difference in the amount of negative ions generated in ridge and valley was $1089.26ea/cm^3$, and the difference of the calculated ion index between the ridge portion and the valley portion was 0.10. The results of this study were provided as the reference weather data of national parks for health management.

• Radiation Oncology Journal
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• v.19 no.2
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• pp.163-170
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• 2001

Purpose : The measurement of radiation survival using a clonogenic assay, the established standard, can be difficult and time consuming. In this study, We have used the MTT assay, based on the reduction of a tetrazolium salt to a purple formazan precipitate by living cells, as a substitution for clonogenic assay and have examined the optimal condition for performing this assay in determination of radiation sensitivity. Materials and Methods : Four human cancer cell lines - PCI-1, SNU-1066, NCI-H630 and RKO cells have been used. For each cell line, a clonogenic assay and a MTT assay using Premix WST-1 solution, which is one of the tetrazolium salts and does not require washing or solubilization of the precipitate were carried out after irradiation of 0, 2, 4, 6, 8, 10 Gy. For clonogenic assay, cells in $25\;cm^2$ flasks were irradiated after overnight incubation and the resultant colonies containing more than 50 cells were scored after culturing the cells for $10\~14$ days. For MTT assay, the relationship between absorbance and cell number, optimal seeding cell number, and optimal timing of assay was determined. Then, MTT assay was performed when the irradiated cells had regained exponential growth or when the non-irradiated cells had undergone four or more doubling times. Results : There was minimal variation in the values gained from these two methods with the standard deviation generally less than $5\%$, and there were no statistically significant differences between two methods according to t-test in low radiation dose (below 6 Gy). The regression analyses showed high linear correlation with the $R^2$ value of $0.975\~0.992$ between data from the two different methods. The optimal cell numbers for MTT assay were found to be dependent on plating efficiency of used cell line. Less than 300 cells/well were appropriate for cells with high plating efficiency (more than $30\%$). For cells with low plating efficiency (less than $30\%$), 500 cells/well or more were appropriate for assay. The optimal time for MTT assay was after 6 doubling times for the results compatible with those of clonogenic assay, at least after 4 doubling times was required for valid results. In consideration of practical limits of assay (12 days, in this study) cells with doubling time more than 3 days were inappropriate for application. Conclusion : In conclusion, it is found that MTT assay can successfully replace clonogenic assay of tested cancer cell lines after irradiation only if MTT assay was undertaken with optimal assay conditions that included plating efficiency of each cell line and doubling time at least.

• Journal of Animal Environmental Science
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• v.13 no.2
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• pp.113-120
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• 2007

This study was conducted to measure Nitrogen(N), Phosphate($P_2O_5$), Potassium ($K_2O$), Organic matter(OM) and Moisture content of liquid pig manure by Near Infrared Spectroscopy(NIRS) and to develop an alternative and analytical instrument which are used for measurement of N, $P_2O_5$, $K_2O$, OM, and Moisture contents for liquid pig manure. The liquid pig manure sample's transmittance spectra were measured with a NIRS in the wavelength range of 400 to 2,500 nm. Multiple linear regression and partial least square regression were used for calibrations. The correlation coefficient(RSQ) and standard error of calibration(SEC) obtained for nitrogen were 0.9190 and 2.1649, respectively. The RSQ for phosphate, potassium, organic matter and moisture contents were 0.9749, 0.5046, 0.9883 and 0.9777, and the SEC were 0.5019, 1.9252, 0.1180 and 0.0789, respectively. These results are indications of the rapid determination of components of liquid pig manure through the NIR analysis. The simple analytical instrument for liquid pig manure consisted of a tungsten halogen lamp for light source, a sample holder, a quartz cell, a SM 301 spectrometer for spectrum analyzer, a power supply, an electronics, a computer and a software. Results showed that the simple analytical instrument that was developed can approximately predict the phosphate, organic matter and moisture content of the liquid pig manure when compared to the analysis taken by NIRS. The low predictability value of potassium however, needs further investigation. Generally, the experiment proved that the simple analytical instrument was reliable, feasible and practical for analyzing liquid pig manure.

• Investigative Magnetic Resonance Imaging
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• v.13 no.2
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• pp.152-160
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• 2009

Purpose : To intra-individually compare diagnostic accuracy of high-resolution contrast-enhanced magnetic resonance angiography (CE-MRA) with computed tomography angiography (CTA) and digital subtraction angiography (DSA) for the assessment of supraaortic steno-occlusive disease. Materials and Methods : Twenty-eight patients (20 men, 8 women, 53-79 years of age) underwent supraaortic CE-MRA, CTA and DSA. CE-MRA was performed on two 1.5T MR scanners (voxel dimension: $0.66{\times}0.66{\times}1.1$ or $1.2\;mm^3$), and CTA on 64-slice CT scanners (voxel dimension: $0.42{\times}0.42{\times}0.63\;mm^3$). All the three examinations were completed within 40 days (median 19 days; range 1-40 days). Retrospective evaluation and measurement of diameter of 6 extracranial and 9 intracranial arterial segments was done by 2 experienced radiologists. Results: A total of 420 arterial segments were examined by CE-MRA, CTA and DSA. On DSA, 34 stenoocclusive lesions were noted at extracranial (n= 19) and intracranial (n = 15) vessels. For extracranial stenosis greater than 70%, sensitivity, specificity, positive predictive value (PPV) and negative predictive values (NPV) were 94.7%, 98.7%, 90.0% and 99.3% on CE-MRA, and 94.7%, 99.3%, 94.7% and 99.3% on CTA. For intracranial stenosis greater than 50%, sensitivity; specificity, PPV and NPV were 93.3%, 98.3%, 77.8%and 99.6% on CE-MRA, and 86.7%, 97.9%, 72.2% and 99.1 % on CTA, with DSA as the standard of reference. Conclusion : Supraaortic CE-MRA is as reliable as CTA in depicting the arterial stenosis, and is effective in screening of significant stenosis of both extracranial and intracranial arterial stenosis.

• Journal of Preventive Medicine and Public Health
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• v.32 no.3
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• pp.361-373
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• 1999

Objectives: Receive Operating Characteristic(ROC) curve with the area under the ROC curve(AUC) is one of the most popular indicator to evaluate the criterion validity of the measurement tool. This study was conducted to develop a standardized questionnaire to discriminate workers at high-risk of work-related musculoskeletal disorders using ROC analysis. Methods: The diagnostic results determined by rehabilitation medicine specialists in 370 persons(89 shipyard CAD workers, 113 telephone directory assistant operators, 79 women with occupation, and 89 housewives) were compared with participant's own replies to 'the questionnair on the worker's subjective physical symptoms'(Kwon, 1996). The AUC's from four models with different methods in item selection and weighting were compared with each other. These 4 models were applied to 225 persons, working in an assembly line of motor vehicle, for the purpose of AUC reliability test. Results: In a weighted model with 11 items, the AUC was 0.8155 in the primary study population, and 0.8026 in the secondary study population(p=0.3780). It was superior in the aspects of discriminability, reliability and convenience. A new questionnaire of musculoskeletal disorder could be constructed by this model. Conclusion: A more valid questionnaire with a small number of items and the quantitative weight scores useful for the relative comparisons are the main results of this study. While the absolute reference value applicable to the wide range of populations was not estimated, the basic intent of this study, developing a surveillance fool through quantitative validation of the measures, would serve for the systematic disease prevention activities.

• The korean journal of orthodontics
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• v.28 no.1 s.66
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• pp.17-27
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• 1998

Study on growth change of dental arch is considered to both an important data in orthodontic diagonsis and treatment planning as well as analysis of treatment results , also, arch form is important in anthropology and dentistry, even more so in prosthodontics and orthodontics. In the field of orthodontics, studies on the functional aspect of upper and lower teeth and maintenance of stability of dentition and occlusion were carried out from the early days. Some of the early studies include explanation of growth change in dental arch from measuring directly fom human stroll, and afterwards, cephalometrics x-rays were introduced; accordingly, studies using cephalometric measurement and linear measurements of study models were often performed. By this method, arch width, arch depth and perimeters were measured, and growth change or dental arch was studied. The subject ror this study were sn children(boys and girls or ages from 3 yens to 12 years from Kang-won district and Seoul, who has no history of orthodontic treatment and who show healthy status and normal growth and development. Cephalometric x-ray, panoramic x-ray, and study model were taken for each subject consecutively for 2 years, and the subjects are still followed up. 400 pairs of study models from the past two years were used in this study; mesio-distal diameater of each tooth, intercanine width, intermolar width, canine depth, molar depth and arch perimeters were measured. Afterwards, mean value and each standard deviation of each age group and each gender were obtained, and representation graph were drawn. The following conclusion were obtained. 1. Intercanine width showed gradual increase until the age of 10-years and after that, showed no increase. 2. Intermolar width in upper arch showed gradual increase : intermolar width in lower arch showed no significant chang, and after the age of 9-years, showed increase. 3. Cainine arch depth showed relatively rapid increase after the age of 6-years, and this pattern was more obvious in lower arch. 4. Molar arch depth increased gradually in both archs and it decrease after the age of 10-years : this phenomenon was more prominent in the lower arch. 5. Arch perimeter showed gradual inerease and convert to plateau at the age of 10-years, after that, it decreased. this pattern was more prominent in lower arch.

• Journal of The Korean Association For Science Education
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• v.15 no.2
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• pp.173-184
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• 1995

The purpose of this study was to analyse the problems of 'Science Inquiry Experiment Contest(SIEC)' which was one of 8 programs of 'The 2nd Student Science Inquiry Olympic Meet(SSIOM)'. The results and conclusions of this study were as follows: 1. It needs to reconsider the role of practical work within science experiment because practical work skills form one of the mainstays in current science. But the assessment of students' laboratory skills in the contest was made little account of. It is necessary to remind of what it means to be 'good at science'. There are two aspects: knowing and doing. Both are important and, in certain respects, quite distinct. Doing science is more of a craft activity, relying more on craft skill and tacit knowledge than on the conscious application of explicit knowledge. Doing science is also divided into two aspects, 'process' and 'skill' by many science educators. 2. The report's and checklist's assessment items were overlapped. Therefore it was suggested that the checklist assessment items were set limit to the students' acts which can't be found in reports. It is important to identify those activities which produce a permanent assessable product, and those which do not. Skills connected with recording and reporting are likely to produce permanent evidence which can be evaluated after the experiment. Those connected with manipulative skills involving processes are more ephemeral and need to be assessed as they occur. The division of student's experimental skills will contribute to the accurate assess of student's scientific inquiry experimental ability. 3. There was a wide difference among the scores of one participant recorded by three evaluators. This means that there was no concrete discussion among the evaluators before the contest. Despite the items of the checklists were set by preparers of the contest experiments, the concrete discussions before the contest were necessary because students' experimental acts were very diverse. There is a variety of scientific skills. So it is necessary to assess the performance of individual students in a range of skills. But the most of the difficulties in the assessment of skills arise from the interaction between measurement and the use. To overcome the difficulties, not only must the mark needed for each skill be recorded, something which all examination groups obviously need, but also a description of the work that the student did when the skill was assessed must also be given, and not all groups need this. Fuller details must also be available for the purposes of moderation. This is a requirement for all students that there must be provision for samples of any end-product or other tangible form of evidence of candidates' work to be submitted for inspection. This is rather important if one is to be as fair as possible to students because, not only can this work be made available to moderators if necessary, but also it can be used to help in arriving at common standards among several evaluators, and in ensuring consistent standards from one evaluator over the assessment period. This need arises because there are problems associated with assessing different students on the same skill in different activities. 4. Most of the students' reports were assessed intuitively by the evaluators despite the assessment items were established concretely by preparers of the experiment. This result means that the evaluators were new to grasp the essence of the established assessment items of the experiment report and that the students' assessment scores were short of objectivity. Lastly, there are suggestions from the results and the conclusions. The students' experimental acts which were difficult to observe because they occur in a flash and which can be easily imitated should be excluded from the assessment items. Evaluators are likely to miss the time to observe the acts, and the students who are assessed later have more opportunity to practise the skill which is being assessed. It is necessary to be aware of these problems and try to reduce their influence or remove them. The skills and processes analysis has made a very useful checklist for scientific inquiry experiment assessment. But in itself it is of little value. It must be seen alongside the other vital attributes needed in the making of a good scientist, the affective aspects of commitment and confidence, the personal insights which come both through formal and informal learning, and the tacit knowledge that comes through experience, both structured and acquired in play. These four aspects must be continually interacting, in a flexible and individualistic way, throughout the scientific education of students. An increasing ability to be good at science, to be good at doing investigational practical work, will be gained through continually, successively, but often unpredictably, developing more experience, developing more insights, developing more skills, and producing more confidence and commitment.

• Journal of Korean Society of Forest Science
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• v.81 no.4
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• pp.337-345
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• 1992

In this research, a kinematic wave model was applied for the runoff analysis, Regulation of streamflow was estimated by the calibration of roughness coefficient as a parameter. The data analyzed were obtained from Ananomiya and Shirasaka experimental basins at Tokyo University Forest in Aichi. Estimation methods and characteristics of roughness coefficient as a evaluation method of hydrological function of forest are summarized as follows ; 1. Roughness coefficient($N_s$) indicates the resistance of hillslope to the flowing water of surface runoff. There exists an hypothesis that resistance of hillslope to flowing water increase with the growth forest and development of the $A_o$ layer. 2. Roughness coefficient($N_s$) was estimated by the parameter when the stream direct runoff was calculated by using the kinematic wave. 3. Secular change of '$N_s$' in ananomiya has a curve which has an upper limit and increases exponentially near the limit. The curve quickly increased from 1935 to 1945 when results of afforestation for erosion control were thought to be effective. On the other hand, slight increase of '$N_s$' in Shirasaka indicates that there was not such a big change in the surface of soil layer. 4. The increase of '$N_s$' was related with decrease of direct runoff and increase of base flow. It was recognized that the rate of direct runoff decreased with the improvement of forest physiognomy and the rate of base flow was increased. But absolute value of water runoff per one storm decreased in chronological order.

• Journal of Korean Society of Forest Science
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• v.105 no.4
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• pp.401-413
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• 2016

Forest resources utilization and variable disturbance history have been affected the rarity and conservation value of forest relict trees, which served as habitat for forest biodiversity, important carbon stock and cultural role include human and natural history in South Korea. This study was conducted to establish the baseline data for forest resources conservation by clarifying species diversity, spatial distribution and ecological characteristics (individual and habitat) of forest relict trees (DBH > 300 cm) based on the data getting from mountain trail, high resolution aerial photos and field professionals and field survey. As results, 54 taxa (18 family 32 genus 48 species 1 subspecies 3 variety and 2 form) as about 22% of tree species in Korea was identified in the field. 837 individuals of forest relict trees were observed and the majority of the trees was in Pinaceae, deciduous Fagaceae and Rosaceae, which families are abundant in population diversity. High elevation area was important to relict trees as mean altitudinal distribution was 1,200 m a.s.l as likely affected by human activity gradients and mid-steep slope and North aspect was important environment for the trees remain. Many individuals exhibited 'damage larger branch' (55.6%) and consequent relatively lower mean canopy coverages (below 80%). Synthetically, present diversity and abundance of relict forest trees in South Korea were the result of complex process among climate variation, local weather and biological factors and the trees of big and old were estimated to important forest biodiversity elements. In the future, clarifying the role and function of relict trees in forest ecosystem, in- and ex- situ programmes for important trees and habitat, and activities for building the background of conservation policy such as "Guideline for identifying and measurement of forest relict trees".

• The Korean Journal of Nuclear Medicine Technology
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• v.19 no.2
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• pp.112-114
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• 2015

Purpose Vitamin D to Anti- Rickets both steroid compounds showing activity, By acting on bone tissue secretary and the key to maintain serum Ca homeostasis. The blood level of vitamin D is the largest in D3 that the concentration of the metabolite is reflected in the holding state of vitamin D in vivo. Sunlight to change the 7-dehydrocholesterol in the skin and through the skin to D3, In the liver in combination with the D2 and D3 D4 changes. The Radioimmunoassay(RIA) method is measuring the D 3, the sensitivity can be measured also difficult trace substance to measure the normal test because it is very sensitive, but recently, a check is possible, for the Total D3 in Chemimicroparticle immunoassay(CMIA) or Chemiluminescent immunoassay(CLIA) measuring using microparticle RIA and CMIA(Architect i2000SR) / use the CLIA(DXI-800) method to compare and evaluate the correlation between the tests in the same test items. Materials and Methods Commissioned from January 2014 to March 2015 patients were enrolled in a total of 273 people. 29 out of 273 people conducted by RIA were compared with CMIA, 244 patients were compared with CLIA. Using reagents and equipment were used RIA(Diasource), CMIA(Architect i2000SR, Abbott Diagnostics) / CLIA( Unicel DXi-800, Beckman coulter). Results Correlation of the RIA and CLIA was a R2 = 0.1844 (y = 0.7303x + 3.9005), and the correlation of RIA CMIA is R2 = 0.2762 (y = 0.8862x + 4.56) respectively. (According to statistics, during the same period RIA is Deficiency 4.31%, Insufficiency 90.53%, Sufficiency 5.16%, was Excess 0%, CLIA / CMIA is Deficiency 17.02%, Insufficiency 75.91%, Sufficiency 7.03%, indicating the distribution of 0.03 % Excess) Conclusion Serum vitamin D and parathyroid hormone that show an inverse relationship, the level above which are not parathyroid hormone and vitamin D reduced the increase. The density is different for each study, at most 20 is reported to be the maximum between 30 ng / ml. In Korea it requires a proposed standard of vitamin D deficiency, reference to the WHO lack the case more than 10ng/ml, 20ng/ml and defined by the lack of, if not more than, the IOM, but looking at 12ng/ml or less to the normal to lack, at least 20ng/ml, the reference do not match the deficit under 20ng/ml, 21-29ng/ml relative lack between, was also defined as a sufficient condition for more than 30ng/ml. Although not statistically is between RIA and CLIA two ways to vitamin D levels change according to season match, when seasonally seen in summer as commonly known (April to September), winter (October to March) relative to the increase measured than it was found. Finally, the study on the correlation between the two methods have been expected to result in a consistent and apply the same view high reference value on the graph is difficult. However, there may be differences between the test equipment and methods, and could be especially the case of RIA method using an organic solvent is difficult to compare different methods and correlated view similar trend in vitamin D deficiency and quarterly aspect ratio.