• 한국연소학회:학술대회논문집
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• 1997.06a
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• pp.23-32
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• 1997

Characteristics of the lifted flame which is generated by issuing of the fuel through the miniature nozzle, d=0.164 mm, are studied using the planar laser induced fluorescence technique. OH radical is excited on the $Q_1$(8) line of the $A^2{\Sigma}\ ^+{\leftarrow}\ X^2{\prod}$ (1,0) band transition(283.55 nm) and LIF signals are captured at the bands of (0,0) and (1,1) transition(306-326 nm) using the filters and ICCD camera. Hydroxyl radical(OH) profile for nozzle attached flame shows that OH radical populations at the flame sides and flame tip are larger than those at the base. But for the lifted flame (tribrachial flame) case, those are larger at the flame base than at the flame tip and flame sides. The OH radical is more dense near the center line of flame base at the blowing out. This fact proves the Chung and Lee's blowout theory - blowout occurs when the flame is anchored at the flame axis.

• Structural Engineering and Mechanics
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• v.62 no.1
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• pp.11-20
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• 2017

The base force element method (BFEM) is a new finite element method. In this paper, a degenerated 4-mid-node plane element from concave polygonal element of BFEM was proposed. The performance of this quadrilateral element with 4 mid-edge nodes in the BFEM on complementary energy principle is studied. Four examples of linear elastic analysis for plane frame structure are presented. The influence of aspect ratio of the element is analyzed. The feasibility of the 4 mid-edge node element model of BFEM on complementary energy principles researched for plane frame problems. The results using the BFEM are compared with corresponding analytical solutions and those obtained from the standard displacement finite element method. It is revealed that the BFEM has better performance compared to the displacement model in the case of large aspect ratio.

• Korean Journal of Head & Neck Oncology
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• v.20 no.1
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• pp.49-51
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• 2004

A choristoma is a tumor like mass of normal tissue in an abnormal location. Lingual osseous choristoma, previously known as osteoma of the tongue base, is rare entity. That is defined as a normal bone mass occuring in the soft tissue of either the skin or the mucosa of oral cavity. The cause of osseous choristoma of the tongue is still unknown, but only several theories have been suggested. Because of the rarity of this entity, our purpose is to add our case to the literature, and to discuss the nature of the disease.

• Journal of computational fluids engineering
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• v.6 no.2
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• pp.1-8
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• 2001

Despite the massive effort which has been given to the analysis of the base flows, one commonly occurring case seems to be overlooked. This is for base (rearward facing surface) which is between a subsonic flow and supersonic flow. Potential flows of the air and gas streams are computed for the flow past a separated wake. Then a viscous jet mixing is superimposed on this inviscid solution. Conservation of mass, momentum and energy is achieved by multiple iterations. Despite the iterations, the wake flow field is computed with modest computer requirements.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.6
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• pp.27-34
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• 2015

Dynamic vibration absorbers are widely used in machinery, buildings, and structures, including bridges. Two cases of their usage are considered in this paper. One is a simply supported beam subjected to either a moving force or a sequence of moving forces, which simulates a train-bridge interaction problem. The other is a case where a primary system is mounted on a base that is not grounded and is excited by an external force. The conditions that the dynamic vibration absorbers must meet in these cases are found and compared to those for usual cases where bases of primary systems are grounded.

• Proceedings of the KWS Conference
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• v.43
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• pp.123-124
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• 2004

This study was investigated on the impact toughness and microstructure of welded metal and heat affected zone for Hi Nitrogen TiN Steel. With welding procedures, welding heat input applied were 30, 79 and 264 kJ/cm. TiN steel has shown very small prior austenite grain size for all the welding heat input applied, which was considered to result from the effect of TiN particles. In case of single SAW and EGW welding, the dilution rate of base metal into the weld was not high, resulting that there were no significant effects of base metal chemical composition on the mechanical properties of welds. However, TSAW with double Ypreparation carried very high dilution rate so that TiN steel has impaired the toughness of weld metal because N content in the weld was increased through the dilution of base metal.

• Journal of the Korean Operations Research and Management Science Society
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• v.31 no.3
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• pp.1-10
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• 2006

In this paper we deal with a cell planning issue arisen in a CDMA based multicast network. In a CDMA based wireless network, a terminal can significantly reduce the bit error rate via the cohesion of data streams from multiple base stations. In this case, multiple base stations have to be operated according to a common time line. The cells whose base stations are operated as such are called soft-combined cells. Therefore, a terminal can take advantage of error rate reduction, if the terminal is in a soft-combined cell and at least one neighboring cell is also soft-combined. However, as soft-combining operation gives heavy burden to the network controller, the limited number of cells can be soft-combined. Our problem us to find a limited number of soft-combined cells such that the benefit of the soft-combining operation is maximized.

• Journal of Korean Neurosurgical Society
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• v.58 no.3
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• pp.281-285
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• 2015

Myxomas are rare benign tumors that originate from mesenchymal tissue. They usually develop in the atrium of the heart, the skin, subcutaneous tissue, or bone. Involvement of the skull base with an intracranial extension is very rare and not well-described in the literature. We report a rare case of primary intracranial ossifying myxoma arising from the anterior skull base and mimicking a huge chondrosarcoma, and we review the relevant literature.

• Journal of Korean Neurosurgical Society
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• v.43 no.3
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• pp.165-168
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• 2008

The location of ganglioglioma (GG) within the infratentorial compartment is unusual. The authors report a rare case of GG in the cerebellar hemisphere. A 12-year-old boy suffered from headache and gait disturbance. Neuroimaging studies demonstrated a large enhancing cerebellar mass with cystic components compressing the forth ventricle. After complete resection of the tumor, the patient became symptom free. Histological examination on the tumor disclosed glial cells and dysplastic ganglion cells. Although it is a rare tumor, in the appropriate clinical setting, a GG should be considered in the presence of a cerebellar mass with both solid and cystic components on magnetic resonance images in children.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.970-974
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• 1993

This paper is concerned with an automatic generation of BOM (Bill Of Material) for a bicycle frame set using a knowledge based system. The major components module system includes : (1) Part information retrieval in CAD drawing, (2) BOM code generation rule, and (3) Database interface. The knowledge based system includes a rule base and a fact base. The fact base consists of basic, variant, and optional components of the standard BOMs of frame sets. The rule contains rules for generating new BOM code in case that the specified is not in the database. The system was implemented on a SUN workstation under Open Windows environments. AutoCAD for CAD drawing was also used.