• Journal of Korean Neurosurgical Society
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• v.55 no.2
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• pp.89-91
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• 2014

Chronic encapsulated intracerebral hematoma (CEIH) is a rare cerebrovascular disease that behaves as a slowly expanding lesion with a gradual onset. It is well established that CEIH is associated with arteriovenous malformations; however, CEIH associated with cavernous malformation (CM) is extremely rare. We herein report a case of CEIH associated with CM, and discuss its pathogenesis. A 12-year-old female was admitted to our hospital because of a one week history of progressive headache and nausea. Brain computed tomography scan and magnetic resonance imaging showed an intracerebral hematoma surrounded by edema in the right frontal lobe. One week later, her headache and nausea worsened, and a brain computed tomography scan revealed the enlargement of hematoma. A right frontal craniotomy was performed. The capsule, mass, and hematoma were totally removed. Histological examination confirmed the diagnosis of CEIH associated with CM. Immunohistochemical analysis revealed increased expression of vascular endothelial growth factor (VEGF) and the VEGF receptor-1 in the endothelium and fibroblasts. Our findings suggest that the activated VEGF pathway might have positively contributed to development of CEIH in the present patient.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.11
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• pp.972-978
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• 2012

This paper discusses the parallelization of multifrontal solution method, widely used for finite element structural analyses, for a shared memory architecture. Multifrontal method is easier than other linear solution methods because the solution procedure implies that unknowns can be eliminated simultaneously. Two innovative ideas are introduced to achieve optimal solver performance on a shared memory computer. Those are pairing two frontal matrices and splitting the frontal matrix in order to reduce the temporal memory space required by independent computing tasks. Performance comparisons between original algorithm and proposed one prove that proposed method is more computationally efficient on current multicore machines.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.7 no.4
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• pp.115-120
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• 2008

The fatalities of pedestrian accounted for about 40.0% of all fatalities in Korea (2005 year). In pedestrian involved accident, the most important data to inspect accident is throw distance of pedestrian. The throw distance of pedestrian can be influenced by many variables, such as vehicular frontal shape, vehicular impact speed, the offset of impact point, the height of pedestrian, and road condition. The trajectory of pedestrian after collision can be influenced by vehicular frontal shape classified into sedan type, box type, SUV type and van type. Many studies have been done about pedestrian accident with passenger car model and bus model for simple factors. But the study of pedestrian accident by van type vehicle was much insufficient, and even that the influence of multiple factors such as the offset of impact point was neglected. In this paper, a series of pedestrian kinetic simulation were conducted to inspect relationship between throw distance and multiple factors with using PC-CRASH s/w, a kinetic analysis program for a traffic accident for van type. By based on the simulation results, multi-variate regression was conducted, and regression equation was presented.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.2C
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• pp.194-199
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• 2009

This paper proposes a face detection algorithm that uses geometrical information on face and hair region. This information that face adjoins hair regions can be the important one for face detection. It is also kept in images with frontal, rotated and lateral face. The face candidates are founded by the analysis of skin regions after detecting the skin and hair color regions in an image. Next, the intersected lesions between face candidates and hair's are created. Finally, the face candidates that include the subsets of these regions turn out to be face. Experimental results showed the high detection rates for frontal and lateral faces as well as faces geometrically distorted.

• Korean Journal of Applied Biomechanics
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• v.20 no.2
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• pp.197-204
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• 2010

Scapular position and motion are essential for normal upper limb mobility; Further, the posture of patients with thoracic kyphosis is related to shoulder girdle function and disorder. The purpose of this study was to examine the effects of thoracic posture on the shoulder range of motion and on three-dimensional scapular kinematics. Thirty healthy subjects performed right-arm abduction along the frontal plane while standing in both erect and in slouched trunk posture. The scapular position and rotation, and shoulder and thoracic angles were recorded using a motion analysis system. The scapular upward rotation and internal rotation were significantly altered according to postural tatiges; however, scapular tilt was not affected. Shoulder angle was significantly decreased in the slouched posture as c rpared to tatt in the erect posture. Thus, a slouched posture(thoracic kyphosis) significantly affects the shoulder range of motion and scapular kinematics during shoulder abduction in the frontal plane.

• Journal of Ginseng Research
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• v.26 no.4
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• pp.187-190
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• 2002

Crude synaptic membrane fractions from the frontal cortex, striatum, brain stem and whole brain of rat were prepared to assay the effects of ginseng total saponin (GTS) on [$^3$H]DAGO bindings of the opioid $\mu$-receptors. Scatchard plots analysis binding data demonstrated that GTS (0.1 mg/ml) decreased the affinity of specific [$^3$H]DAGO bindings without changes in B$\_$max/ in the frontal cortex and striatum. On the other hand, GTS did not affect the [$^3$H]DAGO bindings iii the brain stem and whole brain. These results suggest that the regulation of [$^3$H]DAGO bindings by GTS may play roles in the change of the pharmacological responses of $\mu$-opioids.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.11
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• pp.1044-1050
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• 2004

The present study has been conducted to develop a heat pipe heat exchanger for middle-high temperature ranged from 300 to $600^{\circ}C$. Heat transfer rate, overall heat transfer coefficient and temperature effectiveness were investigated using a heat pipe heat exchanger with Dowtherm A as working fluid. Theoretical analysis was also conducted, and the followings were obtained: (1) Heat exchange rate increased as waste gas temperature supplied to evaporator and frontal velocity in condenser increased, (2) Overall heat transfer coefficient increased by $3{\sim}7\%$ as frontal velocity in evaporator and condenser increased, (3) Temperature effectiveness was about $30\%$ in evaporator and was about $40\%$ in condenser, (4) Heat recovery rate was about $38\%$, (5) Pressure drop did not exceed $8\;mmH_{2}O$ under the running condition of $1{\sim}3Nm/s$, (6) Simulation results were corresponded with experimental results.

• Journal of Biomedical Engineering Research
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• v.20 no.1
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• pp.21-27
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• 1999

In order to increase our understanding of the injury mechanism in the child occupant, three year old child model was developed using commercial dynamic package DADS. Total 14 segments and 12 joints were used to compose a model in three points belted condition with booster seat. HYGE sled test case was simulated to validate the developed model. Based on the comparison of the model and published test results, the developed model appears to be a resonable representation of the three year old dummy.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.2
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• pp.63-71
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• 2013

The estimation of occupant injury risk at crash accident is one of the most important assessments for the vehicle crashworthiness performance. The design of safety devices such as occupant restraining system also depend on the kinematics of occupant and its injury risk. The real world in-depth accident investigation provides detailed and realistic information of vehicle damage and occupant injury as well as the accident conditions. This paper introduces a statistical analysis of NASS/CDS database and domestic accident data to correlate speed change, vehicle damage extend, and occupant injury at frontal crash. The maximum crush extend shows a linear relationship with the effective impact speed. The injury risks of the occupant with and without restraining were also respectively quantified with the crush extend. This result can be effectively used for the emergent rescue of crash victims with automatic crash notification system.

• Journal of Biomedical Engineering Research
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• v.29 no.1
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• pp.17-24
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• 2008

The aim of this paper is to report our preliminary results of investigating the spatial focalization of Zen-meditation EEG (electroencephalograph) in alpha band (8-13 Hz). For comparison, the study involved two groups of subjects, practitioners (experimental group) and non-practitioners (control group). To extract EEG alpha rhythm, wavelet analysis was applied to multi-channel EEG signals. Normalized alpha-power vectors were then constructed from spatial distribution of alpha powers, that were classified by Fuzzy C-means based algorithm to explore various brain spatial characteristics during meditation (or, at rest). Optimal number of clusters was determined by correlation coefficients of the membership-value vectors of each cluster center. Our results show that, in the experimental group, the incidence of frontal alpha activity varied in accordance with the meditation stage. The results demonstrated three different spatiotemporal modules consisting with three distinctive meditation stages normally recognized by meditation practitioners. The frontal alpha activity in two groups decreased in different ways. Particularly, monotonic decline was observed in the control group, and the experimental group showed increasing results. The phenomenon might imply various mechanisms employed by meditation and relaxation in modulating parietal alpha.