• Journal of Trauma and Injury
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• v.19 no.2
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• pp.164-172
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• 2006

Background: The authors conducted a retrospective study to evaluate the mechanism of injury, the surgical techniques, the clinical features, the combined injuries, the treatment results, and the surgical complications in patients with atlantoaxial fracture/subluxations. Methods: The authors reviewed 71 cervical fracture/dislocations during a four-year period from September 2002 to August 2006. Among them, there were twenty one C1,2 fracture/subluxations. There were thirteen men (mean age : 43.5 years) and eight women (mean age : 50 years). Their follow-up period was at least 6 months, and the mean follow-up period was 9.6 months. Gardner-Wells tongs traction was used in all patients immediately on presentation. Surgical treatment was performed, depending on the pathologic conditions. Results: Of all 21 cases, 14 cases were injured in motor vehicle accidents, 5 were falls, and 2 were miscellaneous. There were four C1 fracture (5.6%), fourteen C2 fracture (66.7%), one C1 and 2 combined fracture (4.8%), and one C1-2 subluxation (4.8%). The C1 fractures in our series were classified as two Jefferson's fractures and two C1 lateral mass fracture. The C2 fractures were classified as one odontoid type I fracture, two odontoid type II fractures, five odontoid type III fractures, one hangman's fracture, and four C2 body tear-drop fractures. Atlantoaxial fractures were associated with six (28.6%) head injuries, four (19.0%) other spinal injuries, two (9.5%) chest injuries, and three (14.3%) spinal cord injuries. Surgical treatment was performed in nine cases, which included anterior odontoid screw fixation in two cases, transarticular screw fixation with iliac bone graft in one case, posterior fixation by using C2 pedicle screw and C3 lateral mass screw in three cases, lateral mass screw fixation C1-2 with iliac bone graft in one case, O(occipito)-C1-3-4 screw fixation in one case, posterior C2-3 wiring with allograft in one case, and halo vest in six cases. Conservative management was used in the rest of the patients in our trials. Bone fusion was complete in all cases. There were no operation-related complication, except one pin site infection in the case of halo vest. Conclusion: In this study, the choice of appropriate treatment according to the fracture types resulted in safe and effective management of unique atlantoaxial fracture/subluxations.

• The Korea Journal of Herbology
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• v.23 no.2
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• pp.225-233
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• 2008

Objectives : The purpose of the present study was to development of neuroprotective antioxidant agents. For the purpose, we investigated the neuroprotective effect of anti oxidant herb, the root of Polygonum cuspidatum on transient focal cerebral ischemia in rats. Methods : The roots of Polygonum cuspidatum were extracted by 85% MeOH (PCE). Radical scavenging effects were investigated using DPPH assay and TBARs (Thiobarbituric acid reaction substance) assay in brian homogenates. Neuroprotective effect was investigated using transient focal cerebral ischemia rat model (2 h of ischemia, 22 h of reperfusion) by behavioral test and measurement of brain damage using 2, 3, 5-triphenyltetrazolium chloride staining. Results : PCE showed potent and dose dependent radical scavenging effects in DPPH and TBARs assay. Oral administration of PCE reduced brain infarct volume by 29.7% and improved the sensory motor functional deficit by 29% compared with vehicle treated group. Conclusions : PCE showed radical scavenging effects and neuroprotective effect on stroke rat model. Therefore, Polygonum cuspidatum could be a candidate for the development of neuroprotective-antioxidant agents.

• Journal of Korean Society of Transportation
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• v.32 no.1
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• pp.1-12
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• 2014

The tier 3 methodology used in estimation of greenhouse gas emissions from road sectors is based on mileage data. However, such data can neither accurately represent the mileage of regional unit nor have sufficient integrated data reflecting the characteristics by region, vehicle type, fuel type and road type. Such estimation of greenhouse gas emissions is not reliable. Accordingly, the purpose of this study is, firstly to accumulate activity data based on distance traveled which enables us to accurately estimate the amount of green gas emitted by regional unit(emission point), and secondly, to develop a methodology for estimation of greenhouse gas emissions using these data. To do this, the study utilizes the mileage data of Korea Transportation Safety Authority(TS), statistics of registered motor vehicles, statistical yearbook of traffic volume from the Ministry of Land, Infrastructure and Transport(MLIT), the Korea Transport Database of the Korea Transport Institute(KOTI), and average road speed by local government. Methodology for estimation by local government level(emission point) is meaningful, because it reflects traffic pattern data including flow in and out and internal traffics. Finally, to verify the methodology presented in this study, it is applied to Seoul. Both greenhouse gas estimates, one by multiplying the average mileage and the number of registered vehicles and the other by multiplying traffic volume and road extension, are less than the amount estimated by the methodology presented in this study.

• Journal of the Korea Convergence Society
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• v.9 no.4
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• pp.1-7
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• 2018

Electric motors for electric vehicles differ in efficiency characteristics depending on the operation modes, studies for evaluating high efficiency characteristics in low speed and high speed operation modes are very important. Therefore, it is necessary to design method that can change the high torque, high output density, and high efficiency characteristics of driving motors for electric vehicles. In this paper, the diameter ratio of stator and rotor for the interior permanent magnet synchronous motor is change of designed 0.62, 0.65, and 0.68, respectively, and the efficiency characteristics of the entire operation section, average efficiency characteristics of the city driving modes and express highway driving modes are analyzed. As a result of analyzing the efficiency characteristics of the entire operating section, it was confirmed that as the diameter ratio increases, the high efficiency section moves to the low speed and low torque section and the high efficiency section moves to the high speed and low torque neighborhood as the diameter ratio decreases. As a result of analyzing the average efficiency characteristics in the city driving modes and express highway driving modes, the average efficiency of 0.68 model is analyzed to be more efficient than the 0.63 and 0.65 model ratio, and it is confirmed that it is suitable for city driving modes and express highway driving modes.

• Journal of the Economic Geographical Society of Korea
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• v.19 no.4
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• pp.677-693
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• 2016

Using Social Network Analysis and Trade in Value Added Database(TiVA), this paper examines the world trade network. Main findings are as follows. Firstly, there are three types of industries, which have dominant status in the world value added trade network. Those are the manufacturing industries in the developing countries such as China's electronics industry, the service industries in the developed countries such as U.S. R&D, and the manufacturing industries in the developed countries such as German motor vehicle industry. Secondly, the major hub industries in the world trade network have their own specific types in the brokerage roles. Most interestingly, U.S. service industries such as the R&D, the logistics industry, and the whole sale and retail industry reveal itinerant and liaison brokerage roles. Thirdly, Korean industries have been dominated by Chinese industries. However, the financial industry and the R&D industry could have revealed superior status as the brokerage role of itinerant. This implies Korean industries could sustain their competitiveness of the hubness status only by openness policy in the service industry.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.4
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• pp.353-358
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• 2013

The current interruption method is considered to be an efficient way of measuring the resistance of a fuel cell. In this study, the ohmic area specific resistances (ASRs) of polymer electrolyte fuel cells with different types of bipolar plates were evaluated using the current interruption method. The ohmic ASRs of both a fuel cell with graphite bipolar plates and a fuel cell with graphite foil-based assembled bipolar plates decreased as the current density increased. On the other hand, with increasing cell temperature, the ohmic ASRs of a fuel cell with graphite bipolar plates were decreased by a reduction in the proton transport resistance through the membrane, and the ohmic ASRs of a fuel cell with graphite foil-based assembled bipolar plates were increased by the differences in thermal expansion between different components of the bipolar plates.

• Korean Journal of Environmental Agriculture
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• v.18 no.2
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• pp.135-139
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• 1999

A new effective and economic method was developed, removing interferences such as chlorophyll and lipid from leaves with small amounts of reagents and solvents in order to analyse PAHs(Polycyclic Aromatic Hydrocarbons). The extract from a soxhlet containing $4{\sim}5g$ of leaves and 100ml of dichlormethane and refluxed for 20 hrs was concentrated and eluted with 60ml of a hexane:dichloromethane (1:1) mixture through a column of 9mm wide inner diameter and 130mm long, packed from the bottom with 2.5g of $Al_2O_3$, 1.5g of $SiO_2$and 2g of anhydrous $Na_2SO_4$. The eluent was concentrated and loaded on a GPC column of 20mm wide inner diameter and 280mm long, packed with 12g of Bio-beads. The column was washed with 37ml of the hexane:dichloromethane(1:1) mixture. Another 43ml of the mixture was eluted as a PAH fraction and collected. This eluent was concentrated under gentle nitrogen to $50{\mu}l$ and analysed using GC-MS. The recoveries, obtained by comparing with the amounts of the internal standards of deuterated PAHs were $43.3{\sim}107.5%$(RSD $2.2{\sim}9.5%$).

• Journal of Trauma and Injury
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• v.29 no.1
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• pp.1-7
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• 2016

Purpose: Tracheobronchial injuries caused by trauma are rare, but can be life threatening. The objective of this study was to evaluate the surgical outcome for patients with tracheobronchial injuries and to determine the difference, if any, between the outcomes for patients with penetrating trauma and those for patients with blunt trauma. Methods: From January 2010 to June 2015, 40 patients underwent tracheobronchial repair surgery due to trauma. We excluded 14 patients with iatrogenic injuries, and divided the remaining 26 into two groups. Results: In the blunt trauma group, injury mechanisms were motor vehicle accident (9 cases), free falls (3 cases), flat falls (1 case) and mechanical injury (1 case). In the penetrating trauma group, injury mechanisms were stab wounds (10 cases), a gunshot wound (1 case) and a stab wound caused by metal pieces (1 case). The mean RTS (Revised Trauma Score) was $6.89{\pm}1.59$ (range: 2.40-7.84) and the mean ISS (Injury Severity Score) was $24.36{\pm}7.16$ (range: 11-34) in the blunt group; the mean RTS was $7.56{\pm}0.41$ (range: 7.11-7.84), and the mean ISS was $13{\pm}5.26$ (range: 9-25) in the penetrating trauma group. In the blunt trauma group, 9 primary repairs, 1 resection with end-end anastomosis, 2 lobectomies, 1 sleeve bronchial resection and 1 pneumonectomy were performed. In the penetrating trauma group, 10 primary repairs and 2 resections with end-end anastomosis were performed. Complications associated with surgery were found in one patient in the blunt trauma group, and one patient in the penetrating trauma group. No mortalities occurred in either groups. Conclusion: Surgical management of a traumatic tracheobronchial injury is a safe procedure for both patients with a penetrating trauma and those with a blunt trauma.

• Journal of Trauma and Injury
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• v.24 no.2
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• pp.118-124
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• 2011

Purpose: The incidence of multiple trauma is increasing nowadays and is the leading cause of death among young adults. Initial treatment is well known to be crucial in multiple trauma victims. However, many indiscriminate transfers occur due to the lack of a well-organized trauma system in Korea. The objective of this study is to demonstrate the current serious state in which major trauma patients are transferred to the Emergency Medical Center of a university hospital from another medical center. Methods: From November 2009 to October 2010, we performed a retrospective study to analyze the characteristics of patients who visited the Ajou University Medical Center located in Gyeonggi-do. We evaluated the ISS (injury severity score), and a score over 15 point was identified as major trauma. The major trauma patients were separated into two groups according to the visit route, and the characteristics of each group were analyzed. Results: Among the 88,862 patients who visited to the Emergency Medical Center, trauma patients accounted for 19,950, and 343 of them were evaluated as major trauma patients. Among the 343 patients, 170 patients had been transferred from other medical centers. The proportion of males to females was 3.3:1, and the mean ISS was 22.7. The leading cause of trauma was motor vehicle accidents. Of the total 170 patients, 77.6% were admitted to the Intensive care unit and 36.3% underwent surgery. The 170 patients that had been transferred to our medical center, 78.8% were transferred from Gyeonggi-do, 15.3% were transferred from other regions, and 5.9% were miscellaneous. Conclusion: Almost half of the major trauma victims treat at our medical center had been transferred from other medical centers. Establishing a traumatic system, supported by well-organized trauma centers and emergency medical services, that can reduce inappropriate transfers among medical facilities is essential.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.10
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• pp.3873-3879
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• 2010

Home service robot are not working in the fixed task such as industrial robot, because they are together with human in the same indoor space, but have to do in much more flexible and various environments. Most of them are developed on the base of the wheel-base mobile robot in the same method as a vehicle robot for factory automation. In these days, for holonomic system characteristics, omni-directional wheels are used in the mobile robot. A holonomicrobot, using omni-directional wheels, is capable of driving in any direction. But trajectory control for omni-directional mobile robot is not easy. Especially, azimuth control which sensor uncertainty problem is included is much more difficult. This paper develops trajectory controller of 3-wheels omni-directional mobile robot using fuzzy azimuth estimator. A trajectory controller for an omni-directional mobile robot, which each motor is controlled by an individual PID law to follow the speed command from inverse kinematics, needs a precise sensing data of its azimuth and exact estimation of reference azimuth value. It has imprecision and uncertainty inherent to perception sensors for azimuth. In this paper, they are solved by using fuzzy logic inference which can be used straightforward to perform the control of the mobile robot by means of the fuzzy behavior-based scheme already existent in literature. Finally, the good performance of the developed mobile robot is confirmed through live tests of path control task.