• Economic and Environmental Geology
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• v.3 no.2
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• pp.55-73
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• 1970

The district investigated covers the central and southern portions of the Uiryong Quadrangle amounting to $40km^2$ in area and is bounded approximately by geographical coordinates of $128^{\circ}$ 28' $40^{{\prime}{\prime}}{\sim}128^{\circ}$ 24' 25"E in longitude and $35^{\circ}10{\prime}{\sim}35^{\circ}14^{\prime}06^{{\prime}{\prime}}N$ in latitude. The purpose of this investigation was to provide basic information in drawing up a comprehensive development plan of the copper ore deposits known to exist in the HamanKumbuk district with special emphasis given to the ascertainment of geological and paragenetic characteristics. The area consists chiefly of shale, sandy shale and chert, all belong to Kyongsang System of Cretaceous age. Intruded into these rocks are andesite, granodiorite, basic dikes, and acidic dikes. The mineralization which took place in the area, consists of mostly fissure-filling vein deposits, numbering several tens, with varying magnitudes. The fissures and shear zones created in rocks, such as chert and granodiorite, hosted the deposition of mineralizing vapors and/or hydrothermal solutions along their openings. The strike lengths of these veins vary from 50 to 600 meters in extension and 0.1 to 3 meters in width. Although the degree of fluctuation in width is great, it averages 0.3m. The stuctural patterns, which apparently affected the deposition of veins, are fissure patterns, trend NS to $N30^{\circ}W$, and steep-pitching tension fractures as well as normal fault pattern. Ore minerals associated with vein matters are primarily chalcopyrite and small amounts of scheelite, cobaltiferous arsenopyrite, and gold and silver intimately associated with sulphide minerals. Associated with these ore mineral are pyrite, pyrrhotite, magnetite, specularite and arsenopyrite. Gangue minerals noted are quartz, calcite, chlorite, tourmaline and hornblende. In terms of the compositions of associated minerals, the vein deposits in the district could be grouped under the following four categories: 1. Pyrrhoitite, Arsenopyrite, Gold and Silver Bearing Copper Vein (Type I) 2. Calcite-Scheelite-Copper Vein (Type II) 3. Magnetite-Pyrite-Copper Vein (Type III) 4. Tourmaline Copper Vein (Type IV) Of the four types, the first and the fourth are presently yielding relatively higher grades: of copper ores and concentrates. The estimated ore reserves total some 222,000 metric tons with the following breakdown in terms of metal contents: Name of Mines Au(g/t) Ag(g/t) Cu(%) Reserves(M/T) Kunbuk 15.92 78.69 6,074 60.498 Cheil Kunbuk - - 1.040 60,847 Haman - - 2.688 101,204 222,549 As rehabilitation of old workings and/or exploration of veins at depth proceed, additional estimation of ore reserves may become apparent and necessary. With regard to the problem of beneficiation and upgrading of low-grade ores in the district, it would be advisable to make decisions on location, treating capacity and mill flowsheet after sufficient amount of exploration is completed as suggested in the report.

• Health Policy and Management
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• v.23 no.2
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• pp.152-161
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• 2013

Korea has a single National Health Insurance program and all citizens are covered under this program, accounting 97% of the population, approximately 50 million people. Claims submitted by Health care providers are reviewed by Health Insurance Review and Assessment (HIRA) for the reimbursement. HIRA database contains not only individual beneficiary's information, but also healthcare service information such as diagnosis, procedures, prescriptions and tests for them. HRA database has gained attention as importance source for research due to its rich healthcare information and the demand of HIRA database has increased. Due to its tremendous size, however, researchers have had problems in accessing the database to conduct research. To meet this demand, we conducted a study to develop the inpatient sample data from HIRA database for research. This study has two purposes: 1) to determine a needed sample size; 2) to test reliability and validity of the sample data. We determined an adequate sample size to ensure representativeness and generality with additional consideration for convenience of calculation. The minimum sample size was 729,904 for the generality, and 488,861 for representativeness. After considering the convenience of calculation, our final sample size was 13% of the population, which was about 7.7 million beneficiaries. Age (5 years interval) and gender were used as stratification variables for sampling. In order to examine whether this sample data appropriately reflect population, we tested the reliability and validity of the sample data. From the sample data, we computed average expenditure of total claims per inpatient for 2011, frequency of top 30 disease, estimation of the number of stroke patients from the sample data, and then compared them to those from the population. Results confirmed reliability and validity of the sample data.

• Archives of Plastic Surgery
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• v.37 no.5
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• pp.626-632
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• 2010

Purpose: Nasal bone fractures are often classified as minor injury. However, the incidence of posttraumatic nasal deformity remains alarmingly high. It is because of unnoticed septal fracture. This study was conducted to determine the necessity of septoplasty for patients with nasal bone fracture accompanying grade I septal fractures. Methods: Among 105 patients with nasal bone fractures, 52 who had grade I septal fracture were diagnosed based on physical examination and computed tomography. Patients' age ranged from 14 to 65 years (mean 29.25 years), and 35 were male and 17 female. Patients were divided into 2 groups according to surgical treatment methods: patients who underwent closed reduction only (group 1, n=28) and those who underwent simultaneous closed reduction and septoplasty (group 2, n=24). The treatment outcomes were evaluated by comparing changes in nasal airway volume measured by acoustic rhinometry before the surgery, 3 months and 6 months after the surgery according to the timing of surgical repair and surgical treatment methods. Results: Nasal airway volume increased after the surgery by 17.8% in 3 months after the surgery, 25.2% in 6 months in group 1 and by 22.7% in 3 months, 35.8% in 6 months in group 2. The increase in airway volume after the surgery by 26.3% in 3 months after the surgery, 34.2% in 6 months after the surgery in operation within 1 week after trauma and by 12.1% in 3 months, 22.2% in 6 months after the operation later 1 week after trauma. The difference was statistically significant. Three patients in group 1 complained of intermittent nasal obstruction, two of whom showed a decrease in nasal airway volume by acoustic rhinometry. Conclusion: Most patients with nasal bone fractures accompanying grade I septal fractures have been treated with closed reduction in clinical settings. However, the results of this study suggest that septoplasty be performed after a correct diagnosis of septal fracture is made through comprehensive physical examination and computed tomography. Septoplasty is important to obtain more favorable outcomes and reduce complication.

• Informatization Policy
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• v.18 no.1
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• pp.45-54
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• 2011

The purpose of this study is to analyze the selection behavior decision model of telecommunications service under the telecommunication environments with joining the WiBro and 3GPP LTE-Advanced service at the sam time. The research results are as follows. First, mobile telecommunication service selection behavior is correlated with each other between WiBro and 3GPP LTE-Advanced service. Second, in the bivariate probit model estimates such as age, income, expenditure and income variable are important decision variables of WiBro and 3GPP LTE-Advanced service selection behavior. Gender and service using years, however, are not an important variables. The single and bivariate probit estimate results show the same estimation results. Finally, the two service selecting predictions by using the bivariate probit estimated results, 28.6% of WiBro and 25.3% of 3GPP LTE-Advanced were expected. Also, chance to join the two telecommunications services simultaneously is 19.3%. Therefore, WiBro selection probability is a little higher than 3GPP LTE-Advanced. The implications of these results, the future telecommunications service selection will be determined by economic factors such as income and expenditure. Thus, to enable the WiBro, policy means for reducing the excessive telecommunications expenditure are needed in the future.

• Korean Journal of Environment and Ecology
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• v.24 no.5
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• pp.591-600
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• 2010

We estimated and compared C storages and annual $CO_2$ uptakes by 9 dominant tree species planted along the streets. DBH and age by tree species were measured in the sites selected considering the planting status and distributions of tree species, and biomass, C storage, growth rate, and annual $CO_2$ uptake were estimated for each species. As a result, L. tulipifera, M. glyptostroboides, P. occidentalis were classified into fast-growing group, P. serrulata, G. biloba, Z. serrata, S. japonica, A. palmatum showed intermediate growth rates, and P. densiflora was slow-growing. Average C storage per tree was 205kgC/tree and ranged from 518kgC/tree(L. tulipifera) to 41kgC/tree(P. densiflora). Average annual $CO_2$ uptake by urban street trees over their lifespan ranged from $7.6kgCO_2$/tree/y to $99.1kgCO_2$/tree/y and L. tulipifera was the greatest, followed by glyptostroboides and P. occidentalis, and P. densiflora was the lowest. Total annual $CO_2$ uptake by all street trees in Gyeonggi-do, estimated based on the annual $CO_2$ uptake by each species, was as small as approximately 0.67% of that by forest in Gyeonggi-do. However, urban trees are still important because forest area continues to decrease and urbanization occurs annually in Gyeonggi-do, and should be managed considering their multi-functional aspects, including mitigation of heat island effect and building energy saving(indirect $CO_2$ uptake).

• Journal of Preventive Medicine and Public Health
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• v.51 no.3
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• pp.163-168
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• 2018

Objectives: Due to their developmental characteristics, adolescents have a higher probability than other age groups of experiencing injuries caused by accidents, violence, and intentional self-harm. The severity and characteristics of injuries vary by the intentionality and mechanism of injury; therefore, there is a need for a national-level estimate of the scale and the severity of injuries in adolescents that takes these factors into account. Methods: By using data from the Emergency Department-based Injury In-depth Surveillance Data, National Emergency Department Information System, the Korean National Hospital Discharge In-depth Injury Survey, and cause of death statistics, we calculated the emergency department (ED) visit rate, hospitalization rate, and death rate of injuries per 100 000 adolescents for each injury mechanism. The calculated rates were used to generate the injury pyramid ratio (ratio of death rate to hospitalization rate to ED visit rate) to visualize the scale and the severity of the injury. Results: The mortality rate in adolescents due to injury was 10/100 000; the corresponding rates for hospitalization and ED visits were 1623 and 4923, respectively, resulting in an injury pyramid ratio with the general pyramid form, with a 1:162:492 ratio of deaths to hospitalizations to ED visits. The mortality rate due to suicide/intentional self-harm was 5/100 000, while 35 were hospitalized for this reason and 74 made ED visits. The pyramid ratio of 1:7:15 for intentional self-harm/suicide showed a steep pyramidal form, indicating considerable lethality. The mortality rate due to motor vehicle collisions (MVCs) was 3/100 000; 586 were hospitalized for this reason, while 1023 made ED visits. The pyramid ratio of 1:195:341 for MVCs showed a gradual pyramid form, indicating that the lethality was low and the scale of injury was high. Conclusions: The main categories of injuries in adolescents were visualized in pyramid form, contributing to an understanding of the scale of each injury by mechanism in terms of levels of death, hospitalization, and ED visits. These findings will be helpful for understanding how to prioritize injuries in adolescents.

• Journal of The Korean Society of Agricultural Engineers
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• v.60 no.2
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• pp.75-84
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• 2018

Thermal stress of livestock has been issued due to recent climate change trends and this causes reproductive disorders, decreased feed consumption, immunosuppression, and increased mortality of animals. Concept of THI has been widely used to quantitatively evaluate the degree of thermal stress for animals, however use of this concept is restricted for animals living in the enclosed facilities such as mechanically ventilated broiler houses. In this study, time-based internal energy flow and variation trends of temperature and humidity were analyzed based on BES technique. Local weather data, insulation characteristics of building materials, heat and moisture generation rate from broilers according to age, algorithm of ventilation operation were adopted for boundary condition of the model to accurately compute THI values inside the mechanically ventilated broiler house. From the BES computation, excess frequency of THI threshold in Jeju city was highest on the assumption that air conditioning equipments were not installed. When general raising density ($39kg\;m^{-2}$) was adopted, total 2,191 hours were exceeded. Excess hours of THI threshold were strongly related to the cumulative air temperature ($R^2=0.87$).

• Journal of Animal Science and Technology
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• v.54 no.6
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• pp.395-400
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• 2012

This study was conducted to estimate the growth curve parameters for the body weight (BW) and body length (BL) of miniature pigs in Korea. Growth curve parameters were estimated through a nonlinear regression model using Gompertz, Logistic, and von Bertalanffy methods. A total of 25 piglets were measured monthly from birth up to 15 months of age to estimate both body weight and length. Results showed that the estimated average values for the body weight (body length) were 31.83 kg (58.77 cm) for the mature weight (A), 3.06 (1.74) for the growth ratio (${\beta}$), and 0.28 (0.52) for the maturing rate (${\kappa}$). Average inflection points showing maximum growth rate estimated each month for body weight were 3.97 kg and 11.70 cm, while for the body length were 1.06 kg and 21.61 cm. Moreover, the estimated maturation rates of the body weight and length for the group of Sire 1 were 0.22 and 0.40 respectively, whereas for the group of Sire 2 these values were 0.34 and 0.39. On the other hand, for the groups of Dam 1, Dam 2, and Dam 3, maturation rates for their body weights were 0.26, 0.28 and 0.33 respectively, while for their body lengths these values were 0.43, 0.37, and 0.38, respectively. The study also indicated a negative relationship between the values of mature weight and maturity rate for the body weight will result to a higher inflection point which is in contrast for the body length where results show that a positive relationship between the values of mature length and the maturity rate will result to a higher inflection point. Furthermore, the growth performance of miniature pig varies across stages but using these estimated growth curve parameters could improve the genetic traits of miniature pig.

• The Korean Journal of Quaternary Research
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• v.1 no.1
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• pp.3-20
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• 1987

With regard to the Quaternary formations in the Korean Peninsula, very few studies have been done specially from a stratigraphic viewpoint. The alluvial sediments filling in the valleys have often been considered as the only formation of Quaternary age (more precisely of the Holocone) and so the Pleistocene was regarded as an erosional or nondepositional episode. This is apparently evident from a quick look at the general geological maps of the Peninsula, which show a lithological sequence of Mesozoic or Paleozoic substrata immediately overlain by Holocene alluvium. Likewise, the Pleistocene period was described in terms of unconformity in most local or regional stratigraphical successions of the Peninsula. Recently several different types of Quaternary formation, besides the so-called Holocene alluvium in the valley plain have been found around the Peninsula. They consist of coastal deposits, marine or fluviatile terrace deposits, ancient valley fill deposits or slope deposits. Some parts of the volcanic sediments in Jeju Is. are also known as the Quaternary sequence. Thus the Quaternary deposits in the Peninsula are far more developed than previously known to gelolgists. Moreover the importance of Quaternary research became recently apparent in Korea due to the shortage of raw materials and to the policy of an optimum land-use. Advanced constructions and land reclamation have required more precise engineering parameters of loose materials and an estimation of land stability. This does not imply only the engineering, or the structural properties of the loose material, but at the same time the basic study of the sediments from the stratigraphical and environmental viewpoints has been necessary. In this connection, Quaternary outcrops specially along the coastal fringe of the Peninsula have been mapped, profiled and sampled for sedimentological, clay-mineralogical and palaeomagnetic studies. All these results are compiled for the core of the Quaternary stratigraphy of the Peninsula.

• Journal of Nutrition and Health
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• v.50 no.6
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• pp.624-644
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• 2017

Purpose: This study analyzed iodine intake by establishing an iodine database of general Korean foods eaten by Korean adults based on the data from the 1998 ~ 2014 KNHANES (Korea National Health and Nutrition Examination Survey). Methods: Data on 56,818 subjects aged 19 years and older were obtained from health behavior interviews and a 24-hour dietary recall survey. Iodine intake of subjects was analyzed according to general characteristics, dietary lifestyle, food groups, and cooking method. Results: An iodine database was established for 312 food items. The mean iodine intake of Korean adults decreased from $641.6{\mu}g$ in 1998 to $236.2{\mu}g$ in 2014 per day. Iodine intake of women was higher than that of men. For age distribution, those aged 30 ~ 49 years constituted more than 39 ~ 46% of subjects by survey year. Regarding iodine intake according to dietary lifestyle, the highest iodine intake was 29.4 ~ 34.4% for lunch while that of breakfast decreased. The highest iodine contribution by food group was seaweed such as kelp, sea mustard, and laver. Conclusion: The results of this study indicate that iodine intake of Korean adults has been decreasing, and iodine intake is associated with the prevalence of thyroid disease. This study provides basic data for the estimation of iodine intake in Korean adults.