• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.2
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• pp.281-287
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• 2009

An eruption failure can be observed for child and adolescent periods when the primary dentition is changed to the permanent dentition through the mixed dentition frequently. The eruption failure can lead to miss erupting times of the tooth, then it will cause a lot of problems including root resorption, esthetic problem, transposition of adjacent tooth, malocclusoin and etc. Especially, the maxillary first molar is importantly concerned with occlusion and growth and is an essential tooth for development and maintenance of occlusion. So, it is a momentous part of more proper occlusal management to find these abnormal cases at the early stage and solve the problems. The sorts of eruption failures of the maxillary first molars can be divided into delayed eruption, impaction and the primary retention and the secondary retention. When physical obstacles cause impaction, first of all they must be removed then we can treat the impaction with observation after removal, surgical exposure or orthodontic traction. If the source of impaction is an ectopic eruption, the treatment can be a brasswire, a pendulum appliance, a space maintainer or space regainer after the extraction of the second deciduous tooth and etc. These cases are made a diagnosis of eruption failures of the maxillary first molars in mixed dentition period and have good prognosises after my treatments. So I reported them.

• Journal of Environmental Health Sciences
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• v.46 no.1
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• pp.35-44
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• 2020

Objectives: The purpose of this study was to compare the health status of residents who were exposed to the Iksan industrial area in the living environment and those who were not exposed to such a source of industrial activity through a questionnaire survey designed to appraise the residents' health levels. Method: The authors conducted a health questionnaire survey of 1,012 residents around Iksan regarding their personal information, physician-diagnosed disease history, odors experienced, and more. Logistic regression was performed to identify the associations between hazardous chemical exposure and physician-diagnosed diseases. Result: Logistic regression shows significant differences in allergic rhinitis, cardiovascular disease, hypertension, dyslipidemia, liver disease, and osteoporosis. Odors were experienced by 88.0% of the survey group. The seasons were summer (71%) and spring (24.9%). Conclusion: For allergic rhinitis, cerebral cardiovascular disease, and hypertension, which were significantly higher in the case group than in the control group in the disease diagnosis and disease treatment history of physicians, it was difficult to completely eliminate the association with odor exposure in the Iksan Industrial Complex. It is considered that it has affected nearby residents. This study means that a correlation between chronic diseases has been found through regression analysis, and furthermore, this result can be used as a basis for sampling for secondary epidemiological surveys.

• KSBB Journal
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• v.16 no.1
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• pp.87-94
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• 2001

The biosynthesis of Lovastatin, a cholesterol lowering agent formed by the filamentous fungus, cerulenin-resistant Aspergillus terreus mutant was studied in shake flasks and bioreactors. The lovastatin production could be improved by fed-batch under the limited condition of carbon source. The relationship between the fungal morphology and the lovastatin production was also examined during the fed-batch cultures. The fed-batch studies in shake flasks were carried out to find the optimum glucose feeding method, and the pulsed feeding of glucose from 3 days onward at 24 hours intervals was found to be optimal to increase the lovastatin production and reduce the average pellet size. When the pH was controlled at around 5.8 during the whole fermentation period, the lovastatin concentration reached 384 mg/L, which is much higher than the values obtained pH-uncontrolled and pH 7.4. The optimal glucose feeding strategies was found that 30 g/L of glucose was added initially in batch mode, and then fed-batch was conducted by continuous addition of glucose solution(180 g/L) from 72 to 240 hr at a rate of 1.2 mL/hr at $28^{\circ}C$, pH 5.8, 400 rpm, and 1.0 vvm. The lovastatin concentration of 547 mg/L was obtained in 168 hr. It was about 1.5 times higher than the value of the batch fermentation.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.663-666
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• 2005

Gas hydrates are ice-like compounds that form at the low temperature and high pressure conditions common in shallow marine sediments at water depths greater than 300-500 m when concentrations of methane and other hydrocarbon gases exceed saturation. Estimates of the total mass of methane carbon that resides in this reservoir vary widely. While there is general agreement that gas hydrate is a significant component of the global near-surface carbon budget, there is considerable controversy about whether it has the potential to be a major source of fossil fuel in the future and whether periods of global climate change in the past can be attributed to destabilization of this reservoir. Also essentially unknown is the interaction between gas hydrate and the subsurface biosphere. ODP Leg 204 was designed to address these questions by determining the distribution, amount and rate of formation of gas hydrate within an accretionary ridge and adjacent basin and the sources of gas for forming hydrate. Additional objectives included identification of geologic proxies for past gas hydrate occurrence and calibration of remote sensing techniques to quantify the in situ amount of gas hydrate that can be used to improve estimates where no boreholes exist. Leg 204 also provided an opportunity to test several new techniques for sampling, preserving and measuring gas hydrates. During ODP Leg 204, nine sites were drilled and cored on southern Hydrate Ridge, a topographic high in the accretionary complex of the Cascadia subduction zone, located approximately 80km west of Newport, Oregon. Previous studies of southern Hydrate Ridge had documented the presence of seafloor gas vents, outcrops of massive gas hydrate, and a pinnacle' of authigenic carbonate near the summit. Deep-towed sidescan data show an approximately $300\times500m$ area of relatively high acoustic backscatter that indicates the extent of seafloor venting. Elsewhere on southern Hydrate Ridge, the seafloor is covered with low reflectivity sediment, but the presence of a regional bottom-simulating seismic reflection (BSR) suggests that gas hydrate is widespread. The sites that were drilled and cored during ODP Leg 204 can be grouped into three end-member environments basedon the seismic data. Sites 1244 through 1247 characterize the flanks of southern Hydrate Ridge. Sites 1248-1250 characterize the summit in the region of active seafloor venting. Sites 1251 and 1252 characterize the slope basin east of Hydrate Ridge, which is a region of rapid sedimentation, in contrast to the erosional environment of Hydrate Ridge. Site 1252 was located on the flank of a secondary anticline and is the only site where no BSR is observed.

• Journal of Korean Academy of Nursing
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• v.23 no.1
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• pp.68-89
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• 1993

This study was conducted to develop a model of a fee schedule for nursing services.'Regardless of the demand for skilled and professional nursing service today, the Korean health insurance system does not furnish a chapter for the nursing service fee schedule. A nation-wide survey of hospital nursing service fee schedules was to provide practical and realistic data about how the variety of nursing services are being charged. From September 1990 to April 1991, data from the fee schedule used by twenty hospitals located in eight large cities which are designated large medical regions in the Korea Health Care and Patient Referral System were collected. Nursing services and the fees charged for them were analyzed. The nursing services were subjected to a secondary analysis with referrence to reports on “nursing services to be charged in Korea”. The total number of nursing services recommended by the literatures was 177 : finally 141 types of nursing services were selected by investigator as chargable nursing services. In addition, data on managerial characteristics of the hospitals were collected to discover influential variables for a nursing fee schedule model. Under the assumption that all the managerial characteristics of the hospitals influenced the fee schedule, the following model was tested : Fee of nursing services (C) = f(A₁, A₂, A₃, A₄, A/sub 5/, A/sub 6/, A/sub 7/, A/sub 8/,) When, A₁ = number of nurses A₂ = the first salary of a nurse educated in a four year A₃ = scale of nursing management division A₄ = location of the hospital A/sub 5/ = the type of hospital management (profit / non-profit) A/sub 6/ = number of hospital beds A/sub 7/ = years of hospital operation A/sub 8/ = number and kinds of clinical divisions The results showed that the model should be built as follows : C = f (A₁, A/sub 4/, A/sub 5/) Each nursing service was applied to the fee schedule with consideration for the professional level and time-taken to provide the services. Detailed fee schedules were presented in the related tables. Of the 141 kinds of nursing services, 24.8% were chargeble to the Korea Health Insurance, 32.6％ of the nursing services were being paid directly by the patienty. The rest of nursing services (42.6％) were not being charged to any source. It was recommened that the Korea Health Insurance Reimbursement system should add a classification system for nursing services that can be used in the national health care program. Further study is needed about how to include 32.6% of the nursing services now being paid for directly by the patients in the health insurance system.

• Journal of Korean Neurosurgical Society
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• v.46 no.5
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• pp.479-483
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• 2009

Objective : A mouse model of spinal cord injury (SCI) could further increase our basic understanding of the mechanisms involved in injury and repair of the nervous system. The purpose of this study was to investigate whether methods used to produce and evaluate photochemical graded ischemic SCI in rats, could be successfully adapted to mice, in a reliable and reproducible manner. Methods : Thirty female imprinting control region mice (weighting 25-30 g, 8 weeks of age) were used in this study. Following intraperitoneal injection of Rose bengal, the translucent dorsal surface of the T8-T9 vertebral laminae of the mice were illuminated with a fiber optic bundle of a cold light source. The mice were divided into three groups; Group 1 (20 mg/kg Rose bengal, 5 minutes illumination), Group 2 (20 mg/kg Rose bengal, 10 minutes illumination), and Group 3 (40 mg/kg Rose bengal, 10 minutes illumination). The locomotor function, according to the Basso-Beattie-Bresnahan scale, was assessed at three days after the injury and then once per week for four weeks. The animals were sacrificed at 28 days after the injury, and the histopathology of the lesions was assessed. Results : The mice in group 1 had no hindlimb movement until seven days after the injury. Most mice had later recovery with movement in more than two joints at 28 days after injury. There was limited recovery of one joint, with only slight movement, for the mice in groups 2 and 3. The histopathology showed that the mice in group 1 had a cystic cavity involving the dorsal and partial involvement of the dorsolateral funiculi. A larger cavity, involving the dorsal, dorsolateral funiculi and the gray matter of the dorsal and ventral horns was found in group 2. In group 3, most of the spinal cord was destroyed and only a thin rim of tissue remained. Conclusion : The results of this study show that the photochemical graded ischemic SCI model. described in rats, can be successfully adapted to mice, in a reliable and reproducible manner. The functional deficits are correlated an increase in the irradiation time and, therefore, to the severity of the injury. The photothrombotic model of SCI, in mice with 20 mg/kg Rose bengal for 5 minutes illumination, provides an effective model that could be used in future research. This photochemical model can be used for investigating secondary responses associated with traumatic SCI.

• Atmosphere
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• v.29 no.4
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• pp.403-416
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• 2019

Precipitation samples were collected at the GAW Stations in Anmyeon-do and Gosan for 10 years (2008-2017) to analyze pH, electrical conductivity and NH₄⁺, Na⁺, K⁺, Mg²⁺, Ca²⁺, SO₄^2-, NO₃^-, Cl^-, and F^- ions. From the analysis, the correlation between pH and rainfall, the composition of precipitation and comparison with other regions, and the results of neutralization characteristics by seasonal and pH were determined. In the comparison of ion balance and conductivity for the validation of analytical data, the correlation coefficients were within the range of 0.996~0.999, implying good linear relationship. The volume-weighted pH of the Anmyeon-do and Gosan areas were 4.7 and 4.9, respectively. The pH of the rainfall was affected by washout and rainout in both areas. The ionic strength of precipitation at Anmyeondo and Gosan were 0.42 ± 0.63 mM and 0.37 ± 0.75 mM, indicating about 27.6% and 35.3% of the total precipitation as per a pure precipitation criterion (10^-4 M), respectively. The composition ratio of ionic species were 44.7% and 57.5% for marine sources (Na⁺, Mg²⁺, Cl^-), 40.6% and 22.2% for the secondary inorganic components (NH₄⁺, nss-SO₄^2-, NO₃^-), and 5.6% and 4.0% for the soil source (nss-Ca²⁺), respectively. The neutralization factor of Anmyeon-do and Gosan were 0.43~0.65 and 0.34~0.48, and the neutralization factors of calcium carbonate were 0.15~0.34 and 0.25~0.30, respectively. Thus, both regions have the highest rate of neutralization caused by ammonia. As pH increased in Anmyeon-do and Gosan, change in calcium carbonate became greater than that in ammonia.

• Journal of Educational Research in Mathematics
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• v.15 no.2
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• pp.177-196
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• 2005

In the Korean curriculum, students learn the concept of sample, sampling and other concepts related to sample and sampling, when they have reached the 10th grade of high school. But before the 10th grade, they have an activity about data collection, data analysis and the formulation of conclusion. We then investigated and analyzed the informal knowledge of students before they receive formal instructions. The results enabled the identification of the maximum response rate for each question that each student agreed or disagreed with. In particular, it didn't agree with how students consider the characteristic of population in the process of sampling, and the students agreed on a sampling process without considering the characteristic of the population or the components that consist the population. It showed that 5th grade students didn't investigate the data connected with sampling, and didn't understand the validity of sample survey process. While, 6th grade students equally understood sample size, sampling process, the reliance of data acquired through sample survey that applied to the source of judgment. But in details, it revealed that student had a misconception, or stayed at a subjective judgment level. The significant point is that many high school students didn't adequately understood a sample size with sampling. Though statistics instruction has traditionally been delayed until upper secondary education, this inquiry convinced us that this delay is unnecessary.

• The Journal of the Korea Contents Association
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• v.16 no.2
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• pp.320-331
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• 2016

This study was conducted to find a practical implication regarding efficient and smooth service utilization including care burden reduction of family caregivers by empirically analyzing the factors influencing the dementia patient home care intention of family caregivers, based on Anderson's behavior model. For this study, the subjects and characteristics suitable for the study purpose were selected using the source data of "A Survey on the Dementia Recognition and Needs" targeting 26 cities and countries in Gyeonggi-do and then secondary analysis was conducted. This study targeted 539 dementia families, and based on Anderson's behavior model, variables related to predisposing factors, enabling factors and need factors were inserted, and hierarchical regression analysis was applied. The analysis result showed that at a significance level of 5%, the home care intention was high when family caregivers were not living in cities, they were spouses or children and their economic level was high as predisposing factors, and the dementia-related attitude was positive as a enabling factor, and the degree of dementia was mild and care burden was low as need factors. Moreover, need factors were relatively important variables among the three factors mentioned above. These findings demonstrate that for improving the home care intention, there is a need to construct a support strategy, which considers the degree of dementia and economic characteristics and develop diverse counseling and education programs for a positive attitude towards dementia and a differentiated strategy depending on regional and family characteristics.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.3
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• pp.323-329
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• 2005

In this paper, performance of a hybrid sequential aerobic-anaerobic natural system was investigated. Continuous aerobic and anoxic conditions were created by alternatively placing waste stabilization pond (WSP) and wale. hyacinth pond (WHP). Two pilot-scale treatment lines were built and operated; The first consists of WSP integrated with WHP and the second of WSP connected with Dark Pond(DP), namely control system ponds which were used to examine the effects of water hyacinth on nitrification and de-nitrification. The overall performance in nitrogen was 86% reduction in WSP-WHP and 36% in WSP-control pond system. Nitrogen was mostly removed by nitrification and de-nitrification which simultaneously occurred in the same water hyacinth ponds. For the de-nitrification, benthic layer was found out to be adequate support as a carbon source. In addition, WSP-WHP system was very effective in reducing phosphorus. Overall P removal efficiency in WSP-WHP is 81%, while it is only 16% in WSP-control. difference in phosphorus reduction between those two systems is thought to be caused by the plants and probably their roots producing extra-cellular materials, but these aspects need to be further studied.