• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.2
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• pp.560-569
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• 2016

Purpose The purpose of this study was not only to explore the factors associated with the survival of OHCA(Out-of-hospital Cardiac Arrest), but to provide ideas for improving the operation of emergency medical system in Korea. Method 90,734 OHCAs(Out-of-hospital Cardiac Arrest) with a cardiac etiology, who had been transported by 119 EMS ambulances for seven years from 2006 to 2012 in Korea, were analyzed. The data had a multilevel structure in that patient's survival in the same region is interrelated, so two-level (patient-region) logistic regression analysis was applied to adjust this correlation. Results The adjusted OR in group who were given CPR(Cardiopulmonary Resuscitation) by a bystander were 1.40 for survival to discharge. In addition, the adjusted OR in the group with an implementation of AED (automated external defibrillator) before arriving in hospital was 2.98 for survival to discharge. we categorized some continuous variables (number of emergency physician, OHCAs volume fo hospital, area deprivation level) into five quintiles. The adjusted OR in the number of emergency physician compared with Q1(lowest) was 1.29(Q2), 2.89(Q3), 3.39(Q4), 4.07(Q5), respectively. the adjusted OR in OHCAs volume of each hospital compared with Q1(lowest) was 2.06(Q2), 3.06(Q3), 3.46(Q4), 4.36(Q5), respectively. Lastly, the adjusted OR in deprivation level compared with Q1(least deprived area) was 0.72(Q4), 0.64(Q5) so that the adjusted OR of survival to discharge tended to decrease in more deprived districts. Conclusion The survival to discharge was better significantly in group given CPR by a bystander and with the implementation of AED before arriving in hospital. The survival to discharge tended to be significantly better in hospitals with a larger number of emergency physicians and higher volume of OHCAs in less deprived districts.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.25 no.6
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• pp.374-385
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• 2013

Sediment particle motions have been numerically simulated over a sinusoidal ripple. Turbulent boundary layer flows are generated by Large Eddy Simulation, and the sediment particle motions are simulated using Lagrangian particle tracking method. Two unsteady flow conditions are used in the experiment by employing two different wave amplitudes while keeping other conditions such as wave period same. As expected, the amount of suspended sediment particles is clearly dependent on the wave amplitude as it is increasing with increasing flow intensity. However, it is also observed that the pattern of suspension may be different as well due to the only different condition caused by wave amplitude. Specially, the time of maximum sediment suspension within the wave period is not coincident between the two cases because sediment suspension is strongly affected by the existence of turbulent eddies that are formed at different times over the ripple between the two cases as well. The role of these turbulent eddies on sediment suspension is important as it is also confirmed in previous researches. However, it is also found the time of these eddies' formation may also dependent on the wave amplitude over rippled beds. Therefore, it has been proved that various flow as well as geometric conditions under waves has to be considered in order to have better understanding on the sediment suspension process over ripples. In addition, it is found that high turbulent energy and strong upward flow velocities occur during the time of eddy formation, which also supports high suspension rate at these time steps. The results indicate that the relationship between the structure of flows and bedforms has to be carefully examined in studying sediment suspension at coastal regions.

• Restorative Dentistry and Endodontics
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• v.30 no.1
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• pp.38-48
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• 2005

The purpose of this study was to compare and evaluate the shaping ability of the three different Ni-Ti file systems used by undergraduate students. Fifty undergraduate students prepared 150 simulated curved root canals in resin blocks with three Ni-Ti file systems - $ProFile^{(R)}$ (PF), Manual $ProTaper^{(R)}$ (MPT), Rotary $ProTaper^{(R)}$ (RPT). Every student prepared 3 simulated root canals with each system respectively. After root canal preparation, the Ni-Ti files were evaluated for distortion or breakage Assessments were made according to the presence of various types of canal aberrations. The pre- and post-instrumented canal images were attained and superimposed. The instrumented root canal width were measured and calculated for the net transportation (deviation) and the centering ratio. Under the condition of this study, both $ProTaper^{(R)}$ systems allowed significantly more removal of root canal wall than the $ProFile^{(R)}$ system. In the important other aspects such as the centering ratio, there was no significant differences between the systems. Novice dental students were able to prepare curved root canals with any kinds of Ni-Ti file systems with little aberration and great conservation of tooth structure. Students want to learn effective methods and at the same time simple rotary procedures. The rotary $ProTaper^{(R)}$ systems were one of the most compatible to these students from the point of view of cutting ability The $ProFile^{(R)}$ system was also compatible in safe and gentle shaping.

• Journal of Bio-Environment Control
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• v.29 no.4
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• pp.440-447
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• 2020

The demand for large-scale horticultural complexes utilizing reclaimed lands is increasing, and one of the pending issues for the construction of large-scale facilities is to establish foundation design criteria. In this paper, we tried to review previous studies on the method of reinforcing the foundation of soft ground. Target construction methods are spiral piles, wood piles, crushed stone piles and PF (point foundation) method. In order to evaluate the performance according to the basic construction method, pull-out resistance, bearing capacity, and settlement amount were measured. At the same diameter, pull-out resistance increased with increasing penetration depth. Simplified comparison is difficult due to the difference in reinforcement method, diameter, and penetration depth, but it showed high bearing capacity in the order of crushed stone pile, PF method, and wood pile foundation. In the case of wood piles, the increase in uplift resistance was different depending on the slenderness ratio. Wood, crushed stone pile and PF construction methods, which are foundation reinforcement works with a bearing capacity of 105 kN/㎡ to 826 kN/㎡, are considered sufficient methods to be applied to the greenhouse foundation. There was a limitation in grasping the consistent trend of each foundation reinforcement method through existing studies. If these data are supplemented through additional empirical tests, it is judged that a basic design guideline that can satisfy the structure and economic efficiency of the greenhouse can be presented.

• The Journal of Korean Society for Radiation Therapy
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• v.21 no.1
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• pp.33-39
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• 2009

Purpose: The aim of this study is to compare patient's body posture and its position at the time of simulation with one at the treatment room using On-board Imaging (OBI) and CT (CBCT). The detected offsets are compared with position errors of Rando Phantom that are practically applied. After that, Rando Phantom's position is selected by moving couch based on detected deviations. In addition, the errors between real measured values of Rando Phantom position and theoretical ones is compared. And we will evaluate target position's accuracy of KV X-ray imaging's 2D and CBCT's 3D one. Materials and Methods: Using the Rando Phantom (Alderson Research Laboratories Inc. Stanford. CT, USA) which simulated human body's internal structure, we will set up Rando Phantom on the treatment couch after implementing simulation and RTP according to the same ways as the real radioactive treatment. We tested Rando Phantom that are assumed to have accurate position with different 3 methods. We measured setup errors on the axis of X, Y and Z, and got mean standard deviation errors by repeating tests 10 times on each tests. Results: The difference between mean detection error and standard deviation are as follows; lateral 0.4+/-0.3 mm, longitudinal 0.6+/-0.5 mm, vertical 0.4+/-0.2 mm which all within 0~10 mm. The couch shift variable after positioning that are comparable to residual errors are 0.3+/-0.1, 0.5+/-0.1, and 0.3+/-0.1 mm. The mean detection errors by longitudinal shift between 20~40 mm are 0.4+/-0.3 in lateral, 0.6+/-0.5 in longitudinal, 0.5+/-0.3 in vertical direction. The detection errors are all within range of 0.3~0.5 mm. Residual errors are within 0.2~0.5 mm. Each values are mean values based on 3 tests. Conclusion: Phantom is based on treatment couch shift and error within the average 5mm can be gained by the diminution detected by image registration based on OBI and CBCT. Therefore, the selection of target position which depends on OBI and CBCT could be considered as useful.

• Korean Journal of Environment and Ecology
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• v.27 no.5
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• pp.592-613
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• 2013

This study was carried out to analyze the vegetation properties, soil characteristic, and ordination of forest in Hongdo island and the results are as follows: Castanopsis cuspidata var. sieboldii community, Quercus acuta community, Machilus thunbergii community, Pinus densiflora community and Carpinus coreana community. The results of importance value on the vegetation of Hongdo island consisted of the following in order: 75.56% of Castanopsis cuspidata var. sieboldii, the highest, 34.84% of Pinus densiflora, 29.11% of Machilus thunbergii, 26.88% of Camellia japonica, 17.79% of Quercus acuta, 15.23% of Dendropanax morbifera, 13.41% of Ligustrum japonicum, 12.67% of Carpinus coreana. Due to the high organic matter, total nitrogen and low pH, the soil properties of Hongdo island are different from those of other forest in Korea. The composition of soil properties in the same areas are as follows: organic matter, total nitrogen, available phosphorous, exchangeable $K^+$, exchangeable $Ca^{2+}$, exchangeable $Mg^{2+}$ contained, and soil pH. The capacities of these chemical properties of the soil ranged from 14.48~25.45%, 0.49~0.90%, 26.00~58.68 mg/kg, $0.64{\sim}1.64cmol^+/kg$, $6.22{\sim}21.5cmol^+/kg$, $2.92{\sim}6.95cmol^+/kg$, and 4.42~5.44 respectively. The results of the correlation between communities and soil conditions of vegetation of Hongdo island by DCCA ordination method are as follows: Castanopsis cuspidata var. sieboldii community was found in the highest soil moisture and followed in order Machilus thunbergii community, Quercus acuta community. The Machilus thunbergii community was found in the highest pH, exchangeable $Ca^{2+}$, exchangeable $Mg^{2+}$, exchangeable $K^+$ and cation exchange capacity. The Carpinus coreana community was found in the highest elevation, total nitrogen, cation exchange capacity, exchangeable $Mg^{2+}$ and followed in order Pinus densiflora community.

• Journal of Korean Society of Forest Science
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• v.53 no.1
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• pp.44-55
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• 1981

Neutral sulfite precooked fir chips were refined in the Asplund Laboratory Defibrator at various temperature ($20^{\circ}C$, $120^{\circ}C$ and $180^{\circ}C$). The effects of refining temperatures on the physical property and morphological structure of the resulting pulps were discussed. Yields of precooked chips (84%, 92% and 100%) and refining temperature affected remarkably the yield of refined pulp, its beatability, sheet strength and morhphological characteristics. Pulp yield and beatability decreased with increasing refining temperature. Fiber surface of unbeaten pulp from precooked chips of 84% yield was to some extent covered by the secondary wall, while that of the pulp form precooked yield of 92% by the compound middle lamella. In the case of uncooked chips, fibers were damaged heavily, and the exposed fiber surface resulted from the equal amount of the secondary wall and the compound middle lamella. In the case of pulps prepared from precooked chips of higher yields (92% and 100%), sheet strength increased linearly as sheet density increased. But at the same sheet density, pulp from lower precooked yield (84%) had better sheet strength after open discharge refining as compared to pressurized refining, because pulp from the former had much amounts of fines fraction of higher water retention value than the latters. And there was observed a little difference in fiber length distribution but nearly similar in its morphology with increasing refining temperature.

• Journal of Applied Biological Chemistry
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• v.52 no.4
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• pp.180-186
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• 2009

Whole plants of Vitex rotundifolia were extracted for 2 days with methylene chloride ($CH_2Cl_2$) followed by extraction of the residue for an additional 2 days. The same procedure was also applied using methanol (MeOH). The two crude extracts were combined and partitioned between $CH_2Cl_2$ and $H_2O$. The organic layer was further partitioned between n-hexane and 85% aq. MeOH, and the aqueous layer was also further fractionated with n-BuOH and $H_2O$, successively. From the 85% aq. MeOH fraction, one compound was isolated through the repeated HPLC. According to the results of physicochemical data including NMR and MS, the chemical structure of the compound was determined as artemetin (1). The antiproliferative effects of the crude extracts, fractions, and compound against HT1080, AGS, MCF-7 and HT-29 human cancer cells were compared with the control by using MTT assay. In the comparative analysis, the 85% aq. MeOH fraction exhibited the strongest antiproliferative effects on human cancer cell lines in a dose-dependent manner (p<0.05). In addition, exposure of compound 1 isolated from 85% aq. MeOH fraction led to strong antiproliferative effect in HT1080 cancer cell lines. These results suggest that the extracts and compound isolated from V. rotundifolia may be used as potential chemopreventive and chemotherapeutic agents.

• Proceedings of the Korean DIstribution Association Conference
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• 2006.08a
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• pp.47-68
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• 2006

This study aims to determine the association structure of the behavioral relationship variables, such as trust, commitment, cooperation, communication and coercive power, in the relationship between the buyers and suppliers of industrial parts. It also investigates the impact of the use of IT technologies on the relationships quality. Data was collected from 216 part suppliers of machinery, electronics and automobiles located in Incheon. Data supported all of the proposed hypotheses. First, it was confirmed that parts suppliers' trust in buyers leads to the commitment into relationships with buyers. Second, cooperation and communication showed a positive influence on parts suppliers' trust in buyers, and coercive power gave a negative influence on trust. Third, the use of IT technologies like Internet and E-Mail between parts suppliers and buyers was verified to have generally a positive influence on the quality of relationships. At the same time, cooperation and communication were confirmed to have a positive influence on each other, and cooperation and coercive power as well as communication and coercive power were confirmed to have negative influence on each other. This study is a pioneering attempt to examine the relationships between suppliers and buyers of industrial parts, and the influence IT technologies on the relationship quality. Also, the findings will be practically much helpful to find how to reinforce the relationships between parts suppliers and buyers.

• Journal of Life Science
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• v.25 no.12
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• pp.1354-1361
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• 2015

This study was aimed to investigate the distribution status and phylogenetic relationship of Myotis aurascens in Jeju Ialnd, which has not clearly confirmed until now. We found three groups of M. aurascens from three different cave enforcements (CEs). The bat population of Jeju Island had smaller levels of HBL and Hfcu, but greater levels of TL, EL, FAL, and Tra than those of the Korean Peninsula population. Jeju bats had wide range in the lengths of FAL and Hfcu comparing to those of European bats. From the bimonthly monitoring to each finding site, we have actually failed to observe those again, estimating that they use those CEs as the daily-roosting place in activating seasons. The sequences of CYTB and COI genes showed identical sequences among Jeju bats tested, indicating that they are maternally related. The results from molecular phylogeny showed that the sequences of these bats located on the same branch with those for M. aurascens in the phylogenetic trees. Besides, the nucleotide sequences of the Jeju bats showed the closest relation with that of Korean Peninsula. Consequently, these findings indicate that the bats of M. aurascens, verified the natural distribution in Jeju Island, have originated from a single maternal origin and differences in morphological and genetic backgrounds form those of Korean Peninsula and the other countries, and had probably immigrated via Korean Peninsula. These findings will contribute as basic information for understanding the migration history and biogeographic relationship of mammals on Jeju Island in East Asia.