• The Journal of Korean Academy of Prosthodontics
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• v.36 no.6
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• pp.867-877
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• 1998

The purpose of this study was to investigate the ideal locations and dimensions of bristles for the patients who were installed with fixed prostheses and severely involved periodontitis. The models of 16 pts were analysed and the resullts were as follows: 1. There were no tooth brushes in the market, which were proper for the patients who were installed with fixed prostheses and had severely periodontally involved teeth. 2. The neck portion of the tooth brush should be narrow as possblly. 3. The size of tooth brush should be analyzed by the size of arch. 4. The width of tooth brush should be analyzed by the degree of bone recession. 5. The custom made tooth brush may be ideal, if possible.

• Proceedings of the KIEE Conference
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• 2001.05a
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• pp.58-61
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• 2001

Under restructuring, not only real power pricing but also reactive power pricing is important for the system operation Especially, making a reasonable reactive power pricing is becoming more important than any other time. In this paper, the authors set a proper power factor and price the portion of the reactive power generation that exceeds the power factor. To apply this method to an optimization problem, we developed optimal power flow based on interior point method. By using this IPM for the power system, the System operator can use this strategy for reactive power generation pricing and also the Generators can got the motivation to generate reactive power.

• The Journal of the Korean dental association
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• v.18 no.2 s.131
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• pp.103-108
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• 1980

The occurrence of odontogenic epithelium in the well of a dentigerous cyst is a well known entity. This epithelium usually remains inactive and does not have clinical significance. However, these small inactive islands of epithelium may be stimulated, resulting in an ameloblastoma. Therefore correct diagnosis and proper treatment are very important. A 15 year-old boy came to the outpatient clinic on August 13, 1979. The Chief complaint was pain, difficulty in mouth opening and swelling of the right mandible of 1 month's durations. With the X-ray filming, it was revealed that dentigerous cyst had been originated from the third molar, occurred in posterior region of the right mandible involving the 1st and the and molar and the portion just beneath the sigmoid notch area. Pus discharged from the gingival sulcus distal to the 2nd molar and it was sure that the cyst had been infected. Enucleation performed with careful excision of all cyst wall was successfully carried out, and recovery and heading were rapid and uncomplicated.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.841-844
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• 1997

Sandwich structure is widely used in various fields of industry due to its excellent strength and stiffness compared with weight. We studied the buckling and bending behavior with respect to the variation of design parameters such as length, height, and thickness of honeycomb sandwich core. We found that as the density and the thickness of core become higher, the value of critical bucking load increased significantly. We found that the effect of bending stress due to critical buckling load resulted in high bending stress and the value of bending stress decreased in half according to the increase of length of core. The effect by bending stress is dominant above the portion of the intersection line between bending stress and the effect of buckling is dominant below the potion of it. We could get proper thickness ratio and density of core according to applied load conditions.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11a
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• pp.145-150
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• 2003

16 APEX floats, autonomous profiling floats deployed as part of the Array for Real-time Geostrophic Oceanography (ARGO) program, are used to understand the currents at 800 m underwater in the southwestern East Sea. The flow penetrates into the Ulleung basin (UB) through two paths： an extension of the southward flowing the North Korean Cold Water along the east coast of Korea and between Ulleung Island and Dok island. Flows at 800 m are observed range 0.2 to 4.29 cm/sec and the variability in the north in the DB is stronger than that in the south. The eddy kinetic energy is found a few $cm^{2}$ $S^{-2}$. In the UB, cyclonic flows from 0.3 - 1.6 cm/see are observed with the bottom topography.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.04b
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• pp.52-57
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• 1995

In order to suggest the proper cutting conditions of the CNC milling machining for the free-from surface, some experiments were carried out. In experiments, the influence of cutting conditions on the inclined spherical surface were examined by geometrical anlysis. In thos study, the roundness and cutting force were measured to know the effect of several cutting conditions on the machined surface and the cutting characteristics were carefully investigated. As the result, it was appeared that rigidder tool must be used and the cutting speed must be maintained constantlyfor more effective machining. It can be also known from the experiments that the improved machining surface obtained under about 80 degree, but coarse surface obtained over about 80 degree because of the existance of immproper shape of ball-end mill at the extreme portion.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.728-736
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• 1996

Solid/Liquid(S/L) separation is crucial for biological treatment of animal wastewater. Liquid portion from S/L separation has less BOD-load and proper post-strip treatment can be obtained . Screen or declined sieve was normally used to separate the solid parts. For better separating efficiency a vibration and a cylindrical separator were constructed and tested. The results are summarized as follows : Solids removal efficiency and moisture content of separated solid were 15-26% and 85-88%, respectively for the vibration separator. For the cylindrical separator, solid removal efficiency and moisture content of solid were 16-39% and 86-89% , respectively. The greatest amount of drymatter was obtained when operating vibration separator with 10。 inclination and 100% vibrating power. For the cylindrical separator maximum efficiency was obtained with 40rpm and 19 inclination . The vibration and the cylindrical separator have shown 21% and 26% in BOD removal, respectively. These two types of separator were proved to be applicable methods for animal wastewater separation.

• Journal of Chest Surgery
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• v.27 no.1
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• pp.43-47
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• 1994

Prompt recognition and proper treatment of esophageal perforation or rupture may ax~ert death or minimize complications. We have experienced sixteen patients of esophageal perforation at the department of thoracic and cardiovascular surgery, Hallym Medical college during the period fromJan. 1986 to Sep. 1993. The ratio between male and female patient was 13:3 and their age ranged from 23 years to 67 years old. The major cause of esophageal perforations was spontaneous rupture in 7 cases[45%], surgical trauma in 2 cases[12%], instrumental trauma in 2 cases[12%], and others in 5 cases[31%]. The common site of esophageal perforation was in the lower third portion of the esophagus[10 cases, 62%]. The most consistent symptom of esophageal perforation was chest pain in 11 cases, temperature elevation within a few hours was 9 cases.Contrast roentgenographic studies demonstrated the perforation in all but 2 of the 16 patients. The frequent complications of esophageal perforation were empyema in 7 cases[45 %] and mediastinitis in 2 cases[12%]. fourteen patients had suture closure and drainage with 2 deaths, and 2 patient received only drainage procedures. The mortality rate was 12%[2 cases] and cause of death was sepsis and aortic rupture.

• The Korean Journal of Pain
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• v.8 no.2
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• pp.293-297
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• 1995

Despite applying recent advances in research and technology and taking into acount proper histories and performing thorough physical examinations, a high percentage of patients with low back pain have no identifiable pathology. Problems especially of the sacroiliac joint are commonly missed. The purpose of this article is to describe the effects of sacroiliac injection of local anesthetics and corticosteroids on patients with acute sacroiliac sprain. The sacroiliac joints are essentially nonweight-bearing joints that allows a small amount of anteroposterior rotatory movement around transverse axis usually about 5 to 10 cm below the promontory of the sacrum vertically. The ligamentous portion of sacroiliac joint is vulnerable to rotatory movement particularly when the individual is in an awkward position. Injections of 3 ml of 2% lidocaine and 10 mg of methylprednisolone were given twice at two day intervals to 26 patients with acute sacroiliac sprain. Most of those patients obtained excellent results without any adverse effects.

• Particle and aerosol research
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• v.13 no.4
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• pp.165-172
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• 2017

For precise particle measurements in combustion environments, various dilution sampling methods were compared. Dilution equipments using dilution tunnels and hot/cold dilution with porous tube dilutors were most frequently used so far. The combination of porous tube dilutor and ejector diluter has relatively small footprint, and it results in lower particle losses compared to other methods. To determine the portion of condensable particulate matter, proper temperature control and flow control is required.