• Journal of Preventive Medicine and Public Health
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• v.38 no.2
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• pp.132-140
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• 2005

Objectives: To propose a risk-adjustment model from insurance claims data, and analyze the changes in cesarean section rates of healthcare organizations after adjusting for risk distribution. Methods: The study sample included delivery claims data from January to September, 2003. A risk-adjustment model was built using the 1st quarter data, and the 2nd and 3rd quarter data were used for a validation test. Patients' risk factors were adjusted using a logistic regression analysis. The c-statistic and Hosmer-Lemeshow test were used to evaluate the performance of the risk-adjustment model. Crude, predicted and risk-adjusted rates were calculated, and compared to analyze the effects of the adjustment. Results: Nine risk factors (malpresentation, eclampsia, malignancy, multiple pregnancies, problems in the placenta, previous Cesarean section, older mothers, bleeding and diabetes) were included in the final risk-adjustment model, and were found to have statistically significant effects on the mode of delivery. The c-statistic (0.78) and Hosmer-Lemeshow test ($x^2$=0.60, p=0.439) indicated a good model performance. After applying the 2nd and 3rd quarter data to the model, there were no differences in the c-statistic and Hosmer-Lemeshow $x^2$. Also, risk factor adjustment led to changes in the ranking of hospital Cesarean section rates, especially in tertiary and general hospitals. Conclusion: This study showed a model performance, using medical record abstracted data, was comparable to the results of previous studies. Insurance claims data can be used for identifying areas where risk factors should be adjusted. The changes in the ranking of hospital Cesarean section rates implied that crude rates can mislead people and therefore, the risk should be adjusted before the rates are released to the public. The proposed risk-adjustment model can be applied for the fair comparisons of the rates between hospitals.

• The Journal of Korean Physical Therapy
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• v.22 no.4
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• pp.15-20
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• 2010

Purpose: The purpose of this study was to measure changes in the H-reflex and V wave under loading conditions (e.g. prone and standing position) and to investigate whether postural change would affect the H-reflex and V wave in post stroke hemiplegic patients. Methods: Thirty persons with hemiplegia resulting from stroke (20 males, 10 females) participated in this study. Electromyography (EMG) was used to electrically stimulate and record the soleus H-reflexes and V waves under various loading conditions. The normality of the distribution of each variable (H latency, $H_{max}/M_{max}$ ratio, $V_{max}/M_{max}$ ratio) was tested using the Kolmogorov-Smirnov test. The means of normally distributed continuous data were assessed by independent t-test (${\alpha}$=0.05). Results: There were statistically significant differences in $H_{max}/M_{max}$ ratio (p<0.01), $V_{max}/M_{max}$ ratio (p<0.01), H latency (p<0.01) among the prone and standing position. Conclusion: We found that the H-reflex and V wave in standing position was more active to weight bearing load than prone position.

• Korean journal of applied entomology
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• v.45 no.3 s.144
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• pp.261-268
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• 2006

Ten species of subtropical macro-moths including Squamura sp. of Metarbelidae, were discovered at Is. Daecheong in the West Sea. The other nine species are Zeuzera sp., Setora baibarana (Matsumura), Toccolosida rubriceps Walker, Hyposidra talaca (Walker), Celerena signata Warren, Creatonotos transiens (Walker), Vitessa suradeva Moore, Callambulyx rubricosa (Walker), and Dodusa nobilis Walker, and they are mostly distributed in the subtropical area from the southern part of China to Borneo or Java.

• Korean Journal of Plant Resources
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• v.33 no.4
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• pp.398-403
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• 2020

Plagiothecium platyphyllum Mönk (Plagiotheciaceae), a species unrecorded previously in the moss flora of the Republic of Korea (South Korea), was collected in the Surak stream of Mt. Daedun in Jeollabuk-do Wanju-gun Sanbuk-ri. This species was known to be distributed around China, Japan, North Korea, and Europe. The morphological characters of P. platyphyllum's leaf are ovate-lanceolate, and mostly asymmetric, 2.0~2.5 × 1.0~1.4 mm. The margin of the leaf is entirely below and weakly serrulated near the apex. The costae parts are double, unequal, with one branch reaching to the mid-leaf. Median leaf cells are linear-rhomboidal, 80~127 × 10~16 ㎛ and alar cells are rectangular. Central strand is developed in the core of the stem.

• Korean Journal of Plant Taxonomy
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• v.48 no.1
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• pp.43-47
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• 2018

Pimpinella saxifraga L. (Scarlet pimpernel or Burnet saxifrage), a newly introduced species, was found from Baekyakyi oreum (a parasitic cone or cinder cone) in Seogwipo, Jejudo Island. This species is native to Europe and western Asia and is reported as a widely invasive species around the world. Pimpinella saxifraga is distinguished from other related Korean taxa by leaves that are pinnately compound with 3-7 pairs of segments, which vary from simple, ovate, to 2-pinnatisect, with linear lobes. The vernacular name of "Baek-yak-yi-cham-na-mul" was assigned after the name of the cinder cone where it was initially discovered. We provide descriptions of the morphological characters, photographs and a key to allied taxa in Korea. The geographical origin and introduction routes are unknown, but it is highly likely that it was introduced as fodder given its high nutritious value for sheep and cattle or as a medicinal herb. This species invades commonly grasslands and woodlands and prefers dry, well-drained, and calcareous soils. The distribution of this species was analyzed by searching extensively in surrounding Baekyakyi oreum and adjacent cinder cones, but no other populations were observed. It is protected commonly at the edges or inside of the patchy pine forest in the cinder cone from grazing by cattle; given the worldwide invasive nature of this species, special monitoring and management plans should be developed.

• Journal of the Korean Geophysical Society
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• v.9 no.4
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• pp.343-349
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• 2006

In order to study unconsolidated sediments upstream of the Soyang Dam, seismic refraction data were recorded along five profiles of 94 m length. Receiver interval and record length were 2 m and 204 ms, respectively. Recorded data were analyzed using the traveltime tomography and delay-time methods in order to reveal sediment distribution in the investigation site. The acoustic basements are buried at approximately 14 m deep and their thickness shallows to southeast approaching to a hill. On the basement, pre-existing sediments deposited before construction of the Soyang dam lies. This sedimentary layer is composed of paleo-soil and sandy sediments. Above this layer, recent sediments comprise the top layer which is believed to have been deposited since the formation of the dam. Average thickness of this uppermost layer is approximately 1.6 m, which is much thicker than in the downstream.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.9
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• pp.973-980
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• 2015

With their wide geographical distribution, unconventional resources are continuously compared against conventional resources, but their development is expanding because TRRs (Technical Recoverable Resources) are similar to conventional resources. In particular, there is active development of unconventional gas resources such as shale gas, tight gas, CBM (coalbed methane) and gas hydrate. However, it is difficult to calculate the material properties of unconventional resources, especially the gas content, with current geophysical logging technology. Additionally, some overseas companies have monopolies on related equipment and materials. Therefore, this study developed a reservoir PCS (Pressure Core Sampler). It can collect core samples without gaseous loss by maintaining high pressure from the moment the core is sampled and record pressure and temperature in real time. Successful performance testing was also carried out for official verification of the manufactured PCS. The reservoir PCS will contribute to the acquisition of geophysical well logging data as well as accurate and reliable cores.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.9
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• pp.1325-1330
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• 2010

The breakdown of any critical component of a turbine results in the outage of power plants. Unexpected failure decreases equipment utilization and causes enormous economic losses. Currently, we conduct conservative preventive maintenance for a maintenance period that is proposed by a vendor. In the rapidly changing business environment, reliability-based maintenance is required in order to remain competitive and reduce maintenance costs while maintaining the reliability of equipment. In order to determine an appropriate maintenance period for guaranteeing reliability, we must determine the failure probability by carefully analyzing the failure history of the equipment. In this study, we created a database of failure history for power-plant turbines, predicted the best repair time using the Weibull function, and investigated how the appropriate maintenance cycle can be determined.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.12 no.1
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• pp.92-100
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• 2009

This study was carried out to investigate vegetation structure and soil properties of Angelica gigas population distributed in Jeombongsan, Bangtaesan, Odaesan, Gyebangsan and Jirisan. From August 2007 until September 2008, 5m${\times}$5m quadrat was established in native area of Angelica gigas in order to record a dominants and coverage, and soil factors at 20 sites. It was found that the altitude in the distributed areas for Angelica gigas population was 710m or more. Angelica gigas population was classified into Parasencio auriculata var. kamtschatical dominant population, Pseudostellaria palibiniana dominant population, Isodon excisus dominant population and typical dominant population. In the site of study, soil pH, electrical conductivity, soil organic matter, available phosphorous, and exchangeable potassium, exchangeable calcium, exchangeable magnesium, exchangeable natrium concentration and total nitrogen were ranged from 5.1~6.2, 0.1~0.79dS/m, 2.21~22.11%, 9.56~37.97mg/kg, 1.85~23.88cmol+/kg, 0.21~1.18cmol+/kg, 1.07~5.09cmol+/kg, 0.04~0.14cmol+/kg and 0.09~1.04% respectively. The Parasencio auriculata var. kamtschatical dominant population was found in area of high altitude and had high slope degree. But Pseudostellaria palibiniana dominant population was found in area of low altitude and low slope degree. Isodon excisus dominant population was found to have higher soil pH and exchangeable potassium concentration than the other dominant population.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.2 no.2
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• pp.104-111
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• 1990

The water level variation due to the Typhoon around the coast of Pusan in the southern sea of Korea is investigated from the observed tidal record. Water level variations at six stations along the coast are discussed in association with the meteorological data. The characteristics of storm surge at Pusan during Typhoon Thelma in 1987 is analysed using the observed data, and it is performed the numerical simulation of storm surge which includes a inverse barometric effect due to the horizontal distribution of sea sur-face pressure. From the calculation results, the peak value of storm surge in the coast of Pusan was occur-red around the 01：00 July 16th, which is well coincident with the observed water level variation at the Kadukdo. However, the calculated value at the Pusan TBM is inconsistent with the observed one, which is regarded due to a reason that the Tidal Bench Mark (TBM) locates in the channel. In the computation results, the maximum surge occurs at the coast of Nakdong estuary, which is considered primarily due to a topographic effect, and water level variation exceeded 2.5 meter in these areas while only about 60 cm in another coasts.