• The Korean Journal of Pain
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• v.12 no.1
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• pp.157-161
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• 1999

We report a patient with spontaneous intracranial hypotension. In addition to the cardinal feature of a postural headache and a low CSF pressure, the patient also had subdural hematoma demonstrated by brain MRI. Radionuclide cisternography revealed a CSF leakage in the intracranium. CSF leakage from spinal meningeal defects may be the most common cause of this syndrome. The headache is a consequence of the low CSF pressure producing displacement of pain-sensitive structures. Methods of treatment are identical to those for post-dural puncture headaches. We experienced a patient with spontaneous intracranial hypotension developed in the intracranium who was successfully managed with a cervical blood patch.

• Journal of the Korea institute for structural maintenance and inspection
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• v.5 no.2
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• pp.155-162
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• 2001

In this study a structure with viscoelastic and viscous dampers with identical damping coefficient subjected to stationary seismic and wind load were analyzed in time and frequency-domain to compare motion control capability of viscous and viscoelastic dampers. The dampers were placed based on story drift and acceleration obtained from RMS responses. According to the analysis results, the motion control capability of viscous dampers turned out to be superior to that of the viscoelastic dampers for the case of seismic load. On the contrary, in case of wind load, the viscoelastic dampers were more effective in the mitigation of dynamic responses. However, it was also found that the differences were in a narrow margin.

• 유체기계공업학회:학술대회논문집
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• 2003.12a
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• pp.469-475
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• 2003

The performance of a centrifugal compressor composed of an impeller, tandem diffuser rows and axial guide vanes has been predicted numerically and compared with available experimental results on its design rotational speed. The pitchwise-averaged mixing plane method was employed for the boundaries between rotor and stator to obtain steady state solutions. The overall characteristics showed differently according to the relative positions of tandem diffuser rows while the characteristics of impeller showed almost identical. The numerical results agree with the measured data in respect of their tendency. It turned out that 0% of relative positions is the worst case in terms of static pressure recovery and efficiency. According to the experimental results, some pressure fluctuations and malfunction of the compressor were observed for 75% case. However, this numerical calculation using mixing plane method did not capture any of those phenomena. Thus, unsteady flow calculation should be performed to investigate the stability of the compressor caused by different diffuser configuration.

• Journal of Auto-vehicle Safety Association
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• v.14 no.4
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• pp.100-105
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• 2022

Oblique car to car frontal impact is quite common on the road and series of studies have been done to realize this in the lab. At a certain angle of oblique crash a car (ego) is to travel at a speed of xkm/h to hit the other car(traffic) which is approaching to ego at a speed of ykm/h. Symmetry of the speed of two vehicles, x vs. y, is studied with respect to the impulse of the ego vehicle as well as occupant injury. If there is symmetry of speed of two vehicles, number of case studies needed to analyze the oblique frontal impact may decrease: ex. in the case of 30degree oblique crash 40km/h (ego) / 80km/h (traffic) will show the similar behavior as 80km/h (ego) / 40km/h (traffic) crash.

• International Commerce and Information Review
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• v.11 no.3
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• pp.363-390
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• 2009

This study investigates the role of private participation in FTA Negotiation in case of US, Mexico and Japan. We utilize Putnam(1988)'s two stage negotiation model, Schelling Conjecture and Principal-Agent(P-A) theory to understand the role of private sector in FTA Negotiation. Those theories are useful to understand the behavior and interaction of key players such as private sector, congress and government in FTA negotiation. Putnam(1988)'s two stage negotiation model divides the FTA negotiation process into two processes: the external negotiation with foreign country and domestic negotiation with domestic interest group. Principal-Agent(P-A) theory provides the theoretical foundation of Putnam's two stage negotiation model, which is that principal's interest is not identical to the interest of Agent. We showed that the private sector and congress play an important role in FTA negotiation in United States. In case of Mexico, the private sector and government occupy the dominant position in FTA negotiation. In particular, the cooperation of industry and government has been successfully established via COECE in Mexico. In contrast to these countries, the role of private participation in trade policy is relatively low in Japan and Korea.

• Archives of Plastic Surgery
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• v.33 no.5
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• pp.663-665
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• 2006

Purpose: Dermatofibroma is a lesion several millimeters to several centimeters in size, arising from dermis or subcutaneous tissue, mostly at extremities of a middle aged female. It is a benign fibrous tumor that to our knowledge metastasis have not been reported and may recur only locally. Here we report a rare case of 36-year-old female with dermatofibroma arising from back and metastasized to both lungs. Methods: We performed an en-block elliptical mass excision for skin lesion and metastatectomy for multiple nodules of both lungs. Results: Histologically, the tumors of both lungs and skin lesion showed dilated cystic airspaces which were lined by respiratory epithelium with underlying layers of tumor cells. The tumor cells were composed of plump to spindled fibrohistiocytic cells arranged in storiform growth pattern. There were no cellular pleomorphism, atypical mitosis, and necrosis. These are the specific features of a dermatofibroma and we could examined the histologic findings of skin and lungs identical. Thus, this indicates that dermatofibroma of back was metastasized to both lungs. Conclusion: We report this case to notice that dermatofibroma is a benign tumor but it rarely metastasizes.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.2
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• pp.45-53
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• 2013

In this paper, we analyze the typical phase voltage and line current waveform characteristics of the distribution system with 3 phase small synchronous generation source in case with load and non-load group, in order to investigate the power quality for end load connected of generation source. As demonstrated by our experimental results, the distortion and power quality of phase voltage and line current waveform were relatively good for low voltage 3 phase model grids connected of 3 phase small synchronous generation source in case with non-load group. However, distortion and power quality of voltage and current waveform was poor for low voltage 3 phase model grids connected to 3 phase small synchronous generation source in the load group with some phase voltage and frequency difference. From the above results, we conclude that the phase voltage and frequency of 3 phase generation source must be identical to that of distribution system source to maximize the power quality. Also, special attention is required in case of having load group or non-load group to 3 phase generation source.

• Journal of Fashion Business
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• v.10 no.2
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• pp.18-26
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• 2006

In this study, the effects of chitosan pre-treatment on the mordanting effect and dyeability were investigated in the dyeing using Japanese pagoda tree. The chitosan treatment effects were evaluated mainly focused on the colors after dyeing of cotton and nylon fabrics which were treated with acidic aqueous solution of chitosan. In the case of chitosan untreated fabrics, the mordanting effects on the cotton and nylon were insignificant and the dyeability was very low. Regardless of the mordant types(Al, Sn, and Fe), the dyed fabrics exhibited almost identical yellowish colors. In the case of chitosan treated fabrics, dark colors were obtained compared to the case of chitosan untreated and ${\Delta}E$ values were increased significantly. In cotton fabrics, the most excellent result was obtained under the condition of unmordanted and chitosan treated fabrics. This verifies the fact that routin coloring matters establish direct linkages with the chitosan components, which exhibit cationic nature, easily. In nylon fabrics, the effects of mordanting treatment and chitosan treatment are so insignificant that the routin coloring matters are presumed to establish direct dyeing with the nylon molecular chains.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.1
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• pp.36-42
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• 2011

This paper mainly proposes the protective coordination scheme of the microgrid system. The microgrid protection is identical to the conventional protection system separating the normal part and contingency part to reduce damage when the contingency occur at power cables, facilities. But they are different in the protection type. The conventional protection system only considers unidirectional current. However the microgrid protection should be considered not only unidirectional current but also backfeed current because various microsources and loads are installed in the microgrid system. In case the contingency occurs in microsource, when microgrid is interconnected to grid, the protection system should be configured to not separate microgrid from grid before the microsource is isolated to microgrid. And in case of fault occur in power system, the microsources should not isolated to microgrid before the static switch at PCC is tripped to separate from power system. Considering these characteristic of microgird, this paper proposes the protective coordination scheme of microgrid and implemented the on-line real time monitoring system. Especially in case the microgrid is connected to low voltage distribution system with 220/380V voltage level, the proposed protection method with power IT technology can solve the problems when the existing protective devices only applied to the microgrid system.

• Tuberculosis and Respiratory Diseases
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• v.78 no.2
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• pp.128-132
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• 2015

Bronchopulmonary dysplasia (BPD) is related to decreased lung function throughout life. However, the pathology and radiology pattern of BPD of adults are not documented well yet. In this case report, we present BPD case of an adult monozygotic twin showing nearly identical lesions on chest computed tomography (CT). CT images showed mixed areas of ground-glass and reticular opacities in both lungs. They had common histories of pneumonias requiring mechanical ventilations in period of infants. Pulmonary function test of one patient showed a pulmonary insufficiency with airway obstruction. Pathologic findings showed bronchiolar hyperplasia and peribronchiolar fibrosis which was similar to classic BPD patients. Our twin case report might help provide distinguishing pathology and radiology pattern of an adult pulmonary sequelaes of BPD. It might be reasonable to make close follow-up for BPD patients to evaluate the long-term outcomes of BPD survivors.