• Journal of the Korean Society of Manufacturing Process Engineers
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• v.1 no.1
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• pp.101-108
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• 2002

In the grinding process, the degree of the sharpness in wheel gram affects the surface roughness and the dimensional accuracy. If a wheel with dull grains is used, the grinding force will be increased and the surface roughness deteriorated. To produce a precision component, the magnitude of parameters related to the wear amount of a grinding wheel has to be limited. In this study, a variation of the grinding force and the surface roughness were measured to seek the machining characteristics of the W A and CBN wheels. From the wear amount of the grinding wheel and the removal rate of workpiece, the grinding ratio was calculated. And also the wheel life was determined at a rapid decreasing point of the grinding ratio. The difference between the surface of wheel-workpiece before grinding and after wheel life was clearly verified with a microscopic photo.

• Journal of Korean Neurosurgical Society
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• v.46 no.5
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• pp.501-504
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• 2009

Remote cerebellar hemorrhage (RCH) is rare but potentially lethal as a complication of spinal surgery. We recently experienced a case of RCH in a 61-year-old man who showed mental deterioration after lumbar spinal surgery. There was dural tearing with subsequent cerebrospinal fluid (CSF) loss during the surgery. Brain computed tomography scan revealed cerebellar hemorrhage, 3rd and 4th ventricular hemorrhage and pneumocephalus. He underwent suboccipital craniectomy and hematoma removal. The most important pathomechanism leading to RCH after spinal surgery has been known to be venous bleeding due to caudal sagging of cerebellum by rapid leak of large amount of CSF which seems to be related with this case. Dural repair and minimizing CSF loss after intraoperative dural tearing would be helpful to prevent postoperative RCH.

• Journal of Institute of Convergence Technology
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• v.3 no.1
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• pp.9-14
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• 2013

Recently, the development of renewable energy sources in Mongolia has been needed due to climate change and air pollution in Ulaanbaatar as rapid economic growth. Biodiesel can be considered as an alternative fuel for petroleum based diesel in order to decrease air pollution in Ulaanbaatar because of its no emission of particle materials from internal combustion engine in automobile. Rapeseed oil having low cloud point and pour point was suggested as a promising raw material for biodiesel production in Mongolia. Considering high population density and severe air pollution by particle materials and SOx in Ulaanbaatar, prior supplying site of biodiesel in Mongolia was the capital region including Ulaanbaatar. In the production of biodiesel in Mongolia, adsorption process was a effective alternative to washing process for the removal of residual alkali catalyst and reactants due to long winter time in Mongolia. For the stable supply of biodiesel, subsidy and no tax policy is needed in the early stage of biodiesel supply in Mongolia.

• Journal of Korean Neurosurgical Society
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• v.42 no.5
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• pp.410-412
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• 2007

Pleomorphic xanthoastrocytoma (PXA) has been considered as a low grade tumor of adolescents and young adults. Although this tumor often shows cystic component, the hemorrhage within the cyst is extremely rare. The authors report a rare case of cystic PXA with a hemorrhage within the cyst and the mural nodule in the left frontal lobe. A 64-year-old male presented with a week history of the right side hemiparesis. After gross total resection of the tumor, the patient was fully recovered from neurological deficit. It is suggested that this typically benign tumor could be presented with hemorrhage, causing a rapid neurological deterioration. Prompt surgical intervention, especially total removal of the tumor can provide an excellent functional recovery.

• Journal of Powder Materials
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• v.3 no.2
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• pp.91-96
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• 1996

The effect of vacuum annealing on the oxidation behavior of milled WC-15%Co powder mixture has been studied. A cobalt component in the milled powder mixture was oxidized preferentially above 175$^{\circ}C$ in air. The specimens showed a steady increase in weight at 175$^{\circ}C$ but did constant weight followed by rapid increase in specimen weight at the beginning above 20$0^{\circ}C$. Oxidation of the milled powder mixture was significantly suppressed by vacuum annealing at 30$0^{\circ}C$ for 10 h. Suppression of oxidation by vacuum annealing and different oxidation behaviors of the milled powder mixture between 175$^{\circ}C$ and 20$0^{\circ}C$, were attributed to removal of strain energy stored in the cobalt powder during vacuum annealing or oxidation treatment above 20$0^{\circ}C$. The role of stored strain energy on oxidation of milled WC-15%Co powder mixture was proved by X-ray diffraction method and differential thermal analysis.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.1
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• pp.227-231
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• 2001

In this paper recently catastrophic oil spills from tanker casualties have polluted the marine environment. The Sea Prince casualties are analyzed and the systems to be introduced are considered. Also, the establishment of the national contingency plan and the decision-making procedure based on technical analysis are described. Based on the discussions the Rapid Response Technical Support System is derived for the support of salvage and oil spill removal operation. The System will contribute to the protection of life and assets from the marine casualties and to keeping the clean and safe ocean.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.10a
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• pp.610-613
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• 2000

Recently catastrophic oil spills from tanker casualties have polluted the marine environment. In this paper, the Sea Prince casualties are analyzed and the systems to be introduced are considered. Also, the establishment of the national contingency plan and the decision-making procedure based on technical analysis are described. Based on the discussions the Rapid Response Technical Support System is derived for the support of salvage and oil spill removal operation, The System will contribute to the protection of life and assets from the marine casualties and to keeping the clean and safe ocean.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.1113-1115
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• 2002

Mesoporous silica, MCM-41, was synthesized by sol-gel method. The organic structure-directing agent must be removed to make the desired proes. To achieve this, alternative calcination method using microwave oven was adapted to this removal stage. Microwave calcination was shown to provide a novel, rapid and inexpensive method of praparing nanoporous material. It was studied how the porous structure, surface area and pore size distribution were changes under microwave calcination.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.815-820
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• 1993

Robotic technology has been grown up conspicuously by its versatility. KAERI has been involved in one of facets of robot industry to keep abreast of rapid evolving technologies In robotic field and has launched long-term R&D plan to assure the stable nuclear energy. In this paper, the latest development status of teleoperated robot system has been presented with emphasis the configuration of overall control system with 3 dimensional graphic system that provides operators with tele-presence situation. This robot system under development, composed of master-slave arm with controller and graphic simulator, is operated by a master manipulator to enable an installation and removal operation of nozzle dam system for steam generator. Evaluation and analysis has been carried out to get optimal parameters of robot system.

• Journal of Environmental Health Sciences
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• v.33 no.5
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• pp.422-427
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• 2007

The purposes of this study were to investigate the concentration of total coliforms in sewage effluents during the period from August 2004 to October 2005. The removal efficiency range of multi-tube method and plate count method were $31.3{\sim}99.5%$ and $66.8{\sim}99.2%$, respectively. Though a correlation between the multi-tube method and the plate count method in the same sample is low, not only is an experimental procedure very simple, but the time required also is short. The seasonal correlation between methods showed more sensitive spring and summer than autumn and winter. So the study indicated plate count method can be used in rapid and reliance identification of total coliform more than the multi-tube method.