• Journal of the Korean Society of Combustion
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• v.13 no.1
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• pp.10-16
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• 2008

Numerical simulations of freely propagating premixed flames burning mixtures of methane and chlorinated hydrocarbons in fuel are performed at atmospheric pressure in order to understand the effect of chlorinated hydrocarbons on the formation of nitrogen oxide. A detailed chemical reaction mechanism is used, the adopted scheme involving 89 gas-phase species and 1017 elementary forward reaction steps. Chlorine atoms available from chlorinated hydrocarbons inhibit the formation of nitrogen oxides by lowering the concentration of radical species. The reduction of NO emission index calculated with thermal or prompt NO mechanism is not linear and is probably related to the saturation effect as $CH_3Cl$ addition is increased, In the formation or consumption of nitrogen oxide, the $NO_2$ and NOCl reactions play an important role in lean flames while the HNO reactions do in rich flames. The molar ratio of Cl to H in fuel has an effect on the magnitude of NO emission index.

• Proceedings of the Korea Multimedia Society Conference
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• 2001.06a
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• pp.373-377
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• 2001

The telemedicine & distance education system that this paper suggests has been designed on the CTE(Collaborative Telemedicine & distance Education) framework, which is an integrated multimedia environment. This is a CBM-based collaborative telemedicine & distance education type, different from the conventional doctor based general practice, and is an integrated multimedia telemedicine & distance education system capable of many application developments using information super highway. This paper presents the content regarding electronic medical examination chart and data treatment for efficient medical examination and prompt treatment by realizing mutual conversation type remote medical examination system among 3 parties(patient, doctor, pharmacist) on internet base. And, The implementation of this new teaming system should be designed with multimedia application development platform base which is interfaced with computer engineering, computer network technology, CSCW (Computer-Supported Cooperative Work) technology, and education engineering.

• Journal of Korean Neurosurgical Society
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• v.30 no.12
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• pp.1427-1429
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• 2001

Traumatic intracranial aneurysms are rare, compromising less than 1% of intracranial aneurysms. The case of 20-year-old man suffered from delayed frontal intracerebral hematoma, subarachnoid hemorrhage and intraventricular hemorrhage from traumatic pericallosal aneurysm 12 days after head injury is presented. Traumatic pericallosal artery aneurysm is always near the falcine edge, is unrelated to arterial branching point. Sudden movement of brain and artery causes vessel wall injury against the stationary edge of the falx. Because of high mortality rate of ruptured traumatic aneurysm, clinical suspicion must be focused on the prompt diagnostic work-up and early treatment.

• Journal of Korean Neurosurgical Society
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• v.38 no.2
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• pp.136-140
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• 2005

The authors describe two cases of Brown-Sequard syndrome associated with cervical disc herniation. In both cases, magnetic resonance images of the cervical spine showed a large paramedian disc herniation at C5-C6 with ipsilateral severe spinal cord compression. Microsurgical removal of the herniated disc via anterior foraminotomy was performed and complete decompression of the spinal cord was achieved. Postoperatively, the neurological symptoms recovered rapidly and both patients experienced a complete remission of their symptoms. Although Brown-Sequard syndrome is rarely associated with degenerative cervical spine disease, cervical disc herniation should be kept in mind and prompt evaluations are mandatory. To the best of our knowledge, these are the first reported case of Brown-Sequard syndrome produced by cervical disc herniation which was treated by anterior foraminotomy.

• Journal of Korean Neurosurgical Society
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• v.41 no.5
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• pp.340-342
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• 2007

Three-dimensional computed tomographic angiography [CTA], a representative noninvasive radiologic technique, is being widely used for detecting vascular lesions in specific intracranial bleeding under a certain circumstance [acute nontraumatic subarachnoid hemorrhage]. We encountered a case of extravasation of the contrast medium on CTA images that appeared as ribbon-like high-attenuation lesion from an aneurysm at the distal anterior choroidal artery in a young adult moyamoya patient. As CTA is used more frequently, it is imperative to understand such unusual but, potentially lethal image findings to conduct a prompt intervention.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.36 no.9
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• pp.678-684
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• 1987

The identification problem of instrument faults in PWR pressurizer is considered. The instrument failure detection technique in this paper consists of two filters, a normal-mode Kalman filter which estimates plant states in normal operation and a bias estimator which estimates the magnitudes and directions of bias faults. The concept of threshold based on the residual of a Kalman filter in normal operation is introduced. The bias estimator is driven when the absolute value of residual exceeds the threshold. The suggested failure detection algorithm is applied to a PWR pressurizer. Computer simulations show that the prompt detection of bias fault can be performed very successfully when there exist instrument faults.

• Proceedings of the KIEE Conference
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• 2006.07d
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• pp.1821-1823
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• 2006

This paper presents a development of interface device for electro-oculogram(EOG) signal and it's application to the wireless mouse of wearable PC. The interface device is composed of five bio-electrodes for detecting oculomotor motion, several band-pass filters, instrumentation amplifier and a microprocessor. we have first analyzed impedance characteristics between skin and a bio-electrode. since the impedance highly depends on human face, it's magnitude differs from person. this interface device was applied to develop a wireless mouse for wearable PC, as a Bio Machine Interface(BMI). Where in the prompt on PC monitor is controlled by only EOG signals. this system was implemented in a Head Mount Display(HMD) unit. experimental results show the accuracy of above 90%.

• Journal of Korean Library and Information Science Society
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• v.14
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• pp.217-240
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• 1987

The purpose of this study is to analyse the current theses acquisition in university libraries and to suggest some useful findings for the more efficient acquisition of the theses. The results of the study can be summarized as follows (1) Depositary copies of each thesis in the libraries should be increased. (2) Under cooperative efforts, libraries must establish the exchange system of the theses by region or subject or characteristics of universities. (3) Each library should set up concrete selection criteria for the receiving of theses. (4) Development of purchase system would be necessary for economic and prompt acquisition of theses. (5) Theses should be microformed so as to save their storage space. (6) To give su n.0, pport to effective acquisition activity, various bibliographies about theses should be published.

• Korean Journal of Bronchoesophagology
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• v.2 no.2
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• pp.253-257
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• 1996

Deep neck infections were flirty common and a source of considerable morbidity and mortality. Although the advent of antibiotics has reduced the overall number of deep neck infections, they still occur in the general population. There are several new groups of patients at risk for deep neck infections, such as immunocompromised individuals, those with underlying diseases. Prevention of the severe sequale that may be associated with deep neck infections- mediastinitis, airway obstruction, carotid artery hemorrhage, aspiration pneumonia, septicemia - requires a knowledge of various portals of entry for infection, the presenting sign and symptoms, the possible microbiologic features, appropriate laboratory and radiologic workups, therapeutic techniques, and the ongoing medical management. A prompt diagnosis and institution of therapy will shorten the course of required treatment and reduce morbility and mortility. The authors have experienced one case of acute mediastinitis in deep neck infection patient with diabetes mellitus.

• Nuclear Engineering and Technology
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• v.35 no.6
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• pp.523-528
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• 2003

The efficiencies of single escape and double escape peaks were calculated by using Monte Carlo method and compared with measured efficiencies. The efficiency was obtained from the area ratio of escape peak to full energy absorption peak and the full energy absorption peak efficiency. For the escape peak interfered with other $\gamma-ray$ peaks, the net area was obtained by area correction. The GEANT code developed in CERN was used for the Monte Carlo calculation. The calculated efficiencies of the escape peaks agreed with the measurement within $12\%$.