• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.1
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• pp.1-15
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• 2016

Annual litterfall production and leaf area index (LAI, $m^2/m^2$) were estimated using litter traps in Gwangneung, Mt. Taewha and Mt. Gariwang. Annual total litter fall production including branch, bark, others was the highest in Gwangneung($7497.3{\pm}326.5kg/ha/yr$), which had the highest basal area at late successional stage, and followed by Mt. Taewha($5929.1{\pm}225.8kg/ha/yr$) and Mt. Gariwang($3,210.1{\pm}220.1kg/ha/yr$). Mt. Gariwang had the lowest litterfall production due to high elevation and short growing season even with the higher stand density and basal area than Mt. Taewha. Similarly, LAI, which was calculated by multiplying the mass of leaf litter with specific leaf area, was the highest in Gwangneung($5.99{\pm}0.69$) and followed by Mt. Taewha($5.20{\pm}0.24$) and Mt. Gariwang($4.06{\pm}0.42$) and the upper canopy species had the highest leaf area index in every sites (Gwangneung : 4.72, Mt. Taewha : 3.08, Mt. Gariwang : 2.19). However, species specific LAI estimation based on the relationship between basal area and leaf area was limited due to upper canopy species non-proportionality of basal area with LAI. In addition, the comparison between direct and indirect LAI measurement showed the importance of canopy clumping, especially at high density. Our study emphasized the necessity of direct LAI measurement using litter fall traps especially at temperate deciduous forest with diverse species.

• Journal of the Korean earth science society
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• v.34 no.6
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• pp.536-549
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• 2013

This study investigates the damages of and analyzes the social and economic impacts of volcanic ash eruptions in the world in order to estimate the potential volcanic ash impacts in South Korea when Mt. Baekdusan volcano erupts in the future. First, we build a comparison chart called "the impact of volcanic ash" on each economic and social sector by using major volcanic eruptions and we compare the damage with respect to volcanic ash thickness/weights. Secondly, we analyze the social and economic impact from volcanic ash. The economic damage is not likely to occur in South Korea, unless Mt. Baekdusan erupts in winter. However, the potential damage should not be overlooked because the volcanic ash may have a global impact around the world. If Mt. Baekdusan volcano erupts when the wind blows from north or northeast, the volcanic ash may then significantly affect South Korea of which economy is highly dependent on exports. Particularly when the volcanic ash moves to the densely populated metropolitan areas or agricultural areas, the damage can be significant. In preparation for the potential volcanic disasters, the volcanic ash forecast table suitable for South Korea should be prepared. In addition, building a Korean volcanic ash hazard map in advance will have a strategic significance.

• Journal of Environmental Health Sciences
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• v.41 no.1
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• pp.1-10
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• 2015

Objectives: The purpose of this study was to propose an indirect exposure assessment method using a questionnaire survey at a time when direct exposure assessment would be impossible after a chemical accident. Methods: About two weeks after an accident, a questionnaire survey was performed with 1,264 persons from the local community. Variables related to exposure were extracted from the survey contents, weighted and then graded for comparison with subjective symptoms in order to evaluate the extent of exposure. Survey items suitable for reflecting the previous exposure level during the accident were extracted, weighted and divided into quartile ranges. Subjective symptoms showed an increasing tendency with higher exposure level when compared with final exposure level (p<0.01). Results: For the relationship between the final exposure grade and subjective symptoms, as the exposure grade was increasing the rates complaining of symptom also showed an increasing tendency. However, when adjusted for demographic characteristics, there was a tendency for the eye irritation symptom to appear higher in women, and respiratory organ irritation appeared higher in smokers. Conclusions: When the problem of recall bias is considered, this study may not have completely unraveled exposure and the characteristics of the participants can affect subjective symptoms. Nevertheless, the exposure rating method of using a questionnaire showed a significant relationship with symptom level. It can be deemed that assessment of past exposure may be successfully evaluated by questionnaire in cases such as chemical accidents.

• Journal of the Korean Society of Radiology
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• v.6 no.4
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• pp.313-320
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• 2012

Current medical institutions with the development of medical technology to the increased demand for health use of radiation equipment is increasing rapidly. Direct radiation from the patient receives the aim of reducing exposure as much as possible is important and the spatial dose of scattered radiation with in the space to engage in reducing healthcare physician, radiation workers and carers need to reduce indirect exposure. X-ray radiation workers and caregivers in the X-ray room to wearing of protective clothing is advised. However Radiation worker sand caregivers of patients with secondary is done, by wearing protective clothing to wear protective clothing because of the weight and discomfort have been neglected. In this study, based on the presence or absence of clothing scattered radiation from space to measure distances, depending on the horizontal and height by measuring the angle of the importance of wearing protective clothing were investigated.

• Journal of Educational Research in Mathematics
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• v.23 no.3
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• pp.313-333
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• 2013

In this research, the researchers constructed a survey questionnaire for measuring the multicultural competence of Korean mathematics teachers and administered the survey to 309 mathematics teachers. The analysis indicates that Korean mathematics teachers' level of multicultural competence is rather low (the mean is 2.636 and the standard deviation .290). In particular, the mean of the multicultural competence related to mathematics was lower than the mean of the multicultural competence in general. Moreover, there was no significant difference between the groups according to the length of teaching experience, the participation into the course in multicultural teacher education, and the experience of indirect exposure to people of different cultural background. On the contrary, the experience of direct exposure to people of different cultural background and teachers' major led to a significant difference in the within group comparison. Moreover, the analysis showed that mathematics teachers' level of competence in subject matter had significant impact on their teaching practice responsive to students' backgrounds. Based on the results, the researchers presented implications for the development of multicultural mathematics teacher education to enhance mathematics teachers' competence required for their teaching in culturally diverse school.

• Journal of Korea Water Resources Association
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• v.45 no.7
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• pp.729-741
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• 2012

Among the methods of precipitation data acquisition, a rain gauge station has a distinctive advantage of direct measurement of rainfall itself, but multiple stations should be installed in order to obtain areal precipitation data required for hydrological analysis. On the other hand, a rainfall radar may provide areal distribution of rainfall in real time though it is an indirect measurement of radar echoes on rain drops. Rainfall radars have been shown useful especially for forecasting short-term localized torrential storms that may cause catastrophic flash floods. CAPPI (Constant Altitude Plan Position Indicator), which is one of the several types of radar rainfall image data, has been provided on the Internet in real time by Korea Meteorological Administration (KMA). It is one of the most widely available rainfall data in Korea with fairly high level of confidence as it is produced with bias adjustment and quality control procedures by KMA. The objective of this study is to develop an improved way to extract quantitative rainfall data applicable to even very small watersheds from CAPPI using CIVCOM, which is a new image processing method based on a vector-based scheme proposed in this study rather than raster-based schemes proposed by other researchers. This study shows usefulness of CIVCOM through comparison of rainfall data produced by image processing methods including traditional raster-based schemes and a newly proposed vector-based one.

• The Journal of Korean Academy of Prosthodontics
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• v.48 no.1
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• pp.8-15
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• 2010

Purpose: The purpose of this study was to evaluate the effect of various methods of dentin bonding agent application and air abrasion pretreatment on microtensile bond strength between dentin and resin, using a self-etching adhesive system. Material and methods: Thirty freshly extracted human molars were obtained and divided into 6 groups of 5 teeth. A 2-step self etching adhesive system (Clearfil SE Bond) was used for all groups. The control specimens were prepared using a direct immediate bonding technique. The delayed dentin sealing specimens were prepared using an indirect approach without dentin prebonding. The immediate dentin sealing specimens were prepared using dentin prebonding immediately following preparation. Immediate dentin sealing teeth and delayed dentin sealing teeth had provisional restorations using Fermit for two weeks. Then all specimens of each group were divided into two groups of three, depending on air abrasion pretreatment. Composite "crowns" were incrementally built on and specimens were stored in water for 24 hours. All teeth were prepared for a microtensile bond strength test. Bond strength data were analyzed with a one-way ANOVA test, and post hoc comparison was done using the Scheffe's test. Results: The mean microtensile bond strengths of all groups were not statistically different from each other. Conclusion: When preparing teeth for indirect restorations, IDS and DDS with Clearfil SE bond, have no difference on the microtensile bond strength between dentin and resin. Air abrasion pretreatment did not affect the microtensile bond strength when using IDS and DDS with Clearfil SE bond.

• Journal of Food Hygiene and Safety
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• v.36 no.1
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• pp.68-76
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• 2021

Foodborne outbreaks frequently occur worldwide and result in huge economic losses. It is the therefore important to estimate the costs associated with foodborne diseases to minimize the economic damage. At the same time, it is difficult to accurately estimate the economic loss from foodborne disease due to a wide variety of cost components. In Korea, there are a limited number of analytical studies attempting to estimate such costs. In this study we investigated the components of economic cost used in foreign countries to better estimate the cost of foodborne disease in Korea. Seven recent studies investigated the cost components used to estimate the cost of foodborne disease in humans. This study categorized the economic loss into four types of cost: direct costs, indirect costs, food business costs, and government administration costs. The healthcare costs most often included were medical (outpatient) and hospital costs (inpatient). However, these cost components should be selected according to the systems and budgets of medical services by country. For non-healthcare costs, several other studies considered transportation costs to the hospital as an exception to the cost of inpatient care. So, further discussion is needed on whether to consider inpatient care costs. Among the indirect costs, premature mortality, lost productivity, lost leisure time, and lost quality of life/pain, grief and suffering costs were considered, but the opportunity costs for hospital visits were not considered in any of the above studies. As with healthcare costs, government administration costs should also be considered appropriate cost components due to the difference in government budget systems, for example. Our findings will provide fundamental information for economic analysis associated with foodborne diseases to improve food safety policy in Korea.

• Korean Journal of Remote Sensing
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• v.39 no.5_3
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• pp.933-948
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• 2023

Atmospheric aerosols not only have adverse effects on human health but also exert direct and indirect impacts on the climate system. Consequently, it is imperative to comprehend the characteristics and spatiotemporal distribution of aerosols. Numerous research endeavors have been undertaken to monitor aerosols, predominantly through the retrieval of aerosol optical depth (AOD) via satellite-based observations. Nonetheless, this approach primarily relies on a look-up table-based inversion algorithm, characterized by computationally intensive operations and associated uncertainties. In this study, a novel high-resolution AOD direct retrieval algorithm, leveraging machine learning, was developed using top-of-atmosphere reflectance data derived from the Geostationary Ocean Color Imager-II (GOCI-II), in conjunction with their differences from the past 30-day minimum reflectance, and meteorological variables from numerical models. The Light Gradient Boosting Machine (LGBM) technique was harnessed, and the resultant estimates underwent rigorous validation encompassing random, temporal, and spatial N-fold cross-validation (CV) using ground-based observation data from Aerosol Robotic Network (AERONET) AOD. The three CV results consistently demonstrated robust performance, yielding R²=0.70-0.80, RMSE=0.08-0.09, and within the expected error (EE) of 75.2-85.1%. The Shapley Additive exPlanations(SHAP) analysis confirmed the substantial influence of reflectance-related variables on AOD estimation. A comprehensive examination of the spatiotemporal distribution of AOD in Seoul and Ulsan revealed that the developed LGBM model yielded results that are in close concordance with AERONET AOD over time, thereby confirming its suitability for AOD retrieval at high spatiotemporal resolution (i.e., hourly, 250 m). Furthermore, upon comparing data coverage, it was ascertained that the LGBM model enhanced data retrieval frequency by approximately 8.8% in comparison to the GOCI-II L2 AOD products, ameliorating issues associated with excessive masking over very illuminated surfaces that are often encountered in physics-based AOD retrieval processes.

• Journal of Korean Public Health Nursing
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• v.3 no.2
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• pp.5-46
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• 1989

The current medical payment Insurance Rates in Korea stipulate charges for medical treatment by the doctor, pharmaceutist, medical technician and maternity nurse. But unfortunately didn't specify those charges for nursing done by the professional nurse. Only basic nursing fee is accounted insufficiently in current medical insurance fee schedule. therefore, Being face with covering entire people by medical insurance by 1991, It seems that the problems pertaining to operating the hospital and medical insurance system would be incessantly expanded in that no mention is made of medical charges rendered by major medical producer service in the current system, For that reason, this study made an attempt to clarify the importance the professional nursing puts of the current medical payment. The purpose of this study was to accounting nursing fee which diveded into the current medical fee schedule. (Method) 1. Data collection; Importance and difficulties in nursing activities was conducted in 'S' National University Hospital. Total nursing activities were selected 72 items which included direct care and indirect care. This study was conducted to evaluating the degree of importance and difficulties according to nursing activities through questionnaire to 204 RN. and so relative difficulties (acuity) were computered because the nursing cost level of each nursing service was differently established by the equivalent coefficient according to degree of relative difficulty and time required. 2. Calculation of cost according to nursing activities; After 47 nursing activities were selected in General surgery nursing units, calculation of nursing cost was as follows Cost of Nursing activity = (relative difficulty X Average hourly wage and benefits of nurse) + material cost of nursing -t- Average nursing administration cost So, Calculated cost by nursing activities was compared to current non-insured and insurance rate. 3. Calculation of nursing cost by K - DRG ; Total of 578 patients who were hospitalized in General Surgery units from January to March 1988 ware classified by K - DRG After estimation of total nursing cost based on the K-DRG, verified the appropriateness of basic nursing fee in medical insurance rate (Results) 1. Analysis of degree of importance and difficulties were 4.16 and 3.67 based on 5 point scale. This score were judged that it is worthy specifying the nursing fee 2. The nursing cost of 47 nursing service items in general surgery patients showed that the average cost of nursing activity was \1374.5 and The lowest cost was \217 of 'oral administration nursing' item, The highest cost was \11,025 of 'saline enematill clear' item 3. The result of comparison between the calculated cost by nursing activities against the current non-insured and insurance rate showed that 13 items(27.7%) involved to payment of insurance rate, 9 items(19.1%) involved to non-insured rate, remainder 25 items (53.2%) were not charged anywhere of total 47 nursing activities 4. When calculated cost by nursing activities was 100. current insurance rate was 62.3, non-insured rate was 176.6. Therefore this showed that most of non-insured rate were higher than calculated nursing cost. The insurance rate, however, were lower than it. Reim-bursement was imputed to non-insured patients. So the current rate system became estrainged from cost system. When Remainder 25 items of nursing activities compared' to \1390 of daily basic nursing fee per patient belonged to payment as a insurance fee schedule, basic nursing fee schedule was 1-2% of calculated cost of nursing activities. Therefore it showed that nursing fee was not counted adequately in it. 5. Nursing cost by K-DRG estimated in chart review based on counting number of nursing activities and length of stay The result showed that average amount of total nursing cost was \183828.1 Comparison of nursing cost calculated by K- DRG and basic nursing fee schedule showed that only 12.3% of nursing cost was charged (Conclusion) From the above research result, It is fact that nursing prime cost should be estimated more accurately and included adequately in current medical payment system. The payment system of nursing activities should be introduced not only nursing activities of drug administration and injection fee belonged to insurance fee schedule but also most nursing activities belonged not to mekical fee schedule. Even if introducing payment system of nursing activities, It should be estimated scientific method of Accounting nursing cost So nurses could offer nursing care of good quality, thereby they could make a great contribution not merely to the convalescence of the patient but to the promotion of the people's health.