• The Journal of the Korean dental association
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• v.16 no.4 s.107
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• pp.273-278
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• 1978

A girl aged 16 years and I month, had a severe Angle's class III malocclusion, characterized by a retarded and constricted maxilla, anterior and posterior crossbite. This patient underwent extraction of two lower Ist premolar. After extraction, author placed multibanded system in lower dental arch to change the long axis of anterior teeth and delivered removable appliance with Coffin spring in the upper dental arch to expand dental arch. After 13 months, anterior & posterior crossbite was corrected and this patient's profile was improved. Superimposition of pretreatment and posttreatment cephalograms upon the SN line registered at S showed backward downward rotation of the mandible and retrusion of lower lip.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2007.10a
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• pp.334-337
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• 2007

Austenitic stainless steel is used as high temperature components such as gas turbine blade and disk because of its good thermal resistance. In the present investigation, tensile and low cycle fatigue(LCF) behavior of stainless steel for turbine disks was studied at wide temperature range $20^{\circ}C\;{\sim}\;750^{\circ}C$. In the tensile tests, it was shown that elastic modulus, yield strength, ultimate tensile strength decreased when temperature increased. The effect on fatigue failure of the parameters such as plastic strain amplitude, stress amplitude and plastic strain energy density was also investigated. Coffin-Manson and Morrow models were used to adjust experimental data and predict the fatigue life behavior at different mean strain values during cyclic loading of high temperature components.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2002.05a
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• pp.79-84
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• 2002

The bottom-leaded plastic(BLP) packages have attracted substantial attention since its appearance in the electronic industry. Since the solder materials have relatively low creep resistance and are susceptible to low cycle fatigue, the life of the solder joints under the thermal loading is a critical issue for the reliability The represent study established a finite element model for the analysis of the solder joint reliability under thermal cyclic loading. An elasto-plastic constitutive relation was adopted for solder materials in the modeling and analysis. A 28-pin BLP assembly is modeled to investigate the effects of various epoxy molding compound, leadframe materials on solder joint reliability. The fatigue life of solder joint is estimated by the modified Coffin-Hanson equation. The two coefficients in the equation are also determined. A new design for lead is also evaluated by using finite element analysis. Parametric studies have been conducted to investigate the dependence of solder joint fatigue life on various package materials.

• Journal of the Korean Society of Safety
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• v.23 no.6
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• pp.7-13
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• 2008

It is important to prevent roll failure in hot rolling process for reducing maintenance cost and production loss. The relationship between rolling pass schedule and the work roll wear profile will be presented. The roll wear pattern is related with roll catastrophic failure. The irregular and deep roll wear pattern should be removed by On-line Roll Grinder(ORG) for roll failure prevention. In this study, a computer roll wear prediction model under real process working condition is developed and evaluated with hot rolling pass schedule. The method of building wear calculation functions for center portion abrasion and marginal abrasion respectively was used to develop a work roll wear prediction mathematical model. The three type rolling schedule are evaluated by wear prediction model. The optimum roll grinding methods is suggested for schedule tree rolling technique.

• Conservation Science in Museum
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• v.3
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• pp.9-13
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• 2001

Being entrusted with the conservation of Kyongju National Museum, the conservators did a conservation treatment on the iron helmet found in the wooden coffin excavated from No. 35 Tomb in Ga-Zone, Okseong-ri, Pohang, Kyongbuk Province. They reported their work ranging from the collection of and conservation treatment on the artifacts found at the excavation site to the restoration of them to the originals.

• Conservation Science in Museum
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• v.13
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• pp.37-44
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• 2012

White crystals on 46 costumes excavated from Shim Su-Ryun(1534 - 1589)'s tomb were examined their characterization and distribution. In 36 of such samples, white crystals with different shape and hardness were found. The formation of crystals did not correlated with a kind and use of textiles. However, crystals were found in the back side than the front of costume, specially around the marks of shrouding dead body. White crystals from 7 textiles were investigated by EPMA, XRD, or FT-IR. The composition of white crystal was analysed by EPMA and the structure characterization of crystals was used by X-ray diffraction. FT-IR spectroscopy was applied to check if non-crystalline compounds were also present. Mg and P were detected as the main element of white crystals and these compounds were identified a struvite and newberyite, the inorganic mineral magnesium ammonium phosphates. Struvite precipitation are influenced by many factors including concentration of Mg²⁺, NH₄⁺, and PO₄^3- ions, pH, and temperatures. It is assumed that magnesium, phosphorous, ammonia, a base material of struvite comes from decomposition product of human body. Tomb covered with lime, a unique triple-structure in Joseon period offering the basic condition, an anaerobe in a coffin, and high magnesium concentration of outer coffin with lime can be inferred as important factor for precipitation of crystals.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.8
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• pp.62-68
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• 2016

The feeder cable assembly is an automotive part used for telecommunication. If it malfunctions, the control and safety of the automobile can be put at risk. ALT (Accelerated Life Testing) is a testing process for products in which they are subjected to conditions (stress, strain, temperatures, etc.) in excess of their normal service parameters in an attempt to uncover faults and potential modes of failure in a short amount of time. Failure is caused by defects in the design, process, quality, or application of the part, and these defects are the underlying causes of failure or which initiate a process leading to failure. Thermal shock occurs when a thermal gradient causes different parts of an object to expand by different amounts. Thermal shock testing is performed to determine the ability of parts and components to withstand sudden changes in temperature. In this research, the main causes of failure of the feeder cable assembly were snapping, shorting and electro-pressure resistance failure. Using the Coffin-Manson model for ALT, the normal conditions were from Tmax = $80^{\circ}C$ to Tmin = $-40^{\circ}C$, the accelerated testing conditions were from Tmax = $120^{\circ}C$ to Tmin = $-60^{\circ}C$, the AF (Acceleration Factor) was 2.25 and the testing time was reduced from 1,000 cycles to 444 cycles. Using the Bxlife test, the number of samples was 5, the required life was B0.04%.10years, in the acceleration condition, 747 cycles were obtained. After the thermal shock test under different conditions, the feeder cable assembly was examined by a network analyzer and compared with the Weibull distribution modulus parameter. The results obtained showed good results in acceleration life test mode. For the same reliability rate, the testing time was decreased by a quarter using ALT.

• Journal of the Korean Society of Costume
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• v.66 no.8
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• pp.61-77
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• 2016

This study is to understand the meaning, the location, and the construction of Hyeonhun (玄纁) through the records and relics of the Chosun Dynasty. Hyeonhun means farewell gifts for the dead. Hyeonhun was very personal and was considered to be essential ritual supplies. it was newly made for not only first funeral(初葬), but also the second funeral(改葬), was individually made as well as in the couple funeral(夫婦合葬). the Hyeonhun ritual was performed while dressed in a simabok(緦麻服). The ritual started with washing of the hands(盥手) and deep bowing(再拜) twice. The Hyeonhun was placed on the lid of the inner coffin among the 3 coffins in Chosun tomb's way. The Hyeon was placed on the right side and the Hun on the left side of the lid.(玄右纁左). Hyeonhun are comprised of one, two, five of ten pieces. Most of the excavated Hyeonhun were two pieces : Hyeonhunsokbaek(玄纁束帛) consist of ten pieces, of which six were Hyeons and four were Huns. The records indicated that the materials used to make Hyeonhun was silk, but the excavated relics satin and twill, single gauze in the excavated relics advanced than the records.

• Fashion & Textile Research Journal
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• v.14 no.6
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• pp.898-905
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• 2012

This paper develops fashion products that express the beauty of Baekje through an investigation of the unique characteristics of Baekje artifacts. This work can promote the Baekje region and provide cultural goods for local festivals to improve the economic competitiveness of the area. Artifacts from the Muryongwangreung in Gongju (the capital city of Baekje during the Woongjin period)were reinterpreted into a more modern form. Among the Muryongwangreung artifacts, the king and queen's gold coffin as well as chignon ornaments were used as design motifs. These artifacts were stylized into motifs and developed into patterns using Adobe Illustrator CS3 and Adobe Photoshop CS3. The patterns were subsequently applied to the designs of scarves and ties. The color was selected using the CMYK colorway from the Gongju city logo subsequently, a total of 12 designs (including 6 ties and 6 scarves) were developed. The design developed from this research can be applied to diverse products to promote the area. Using the research as a foundation, fashion product development based on the local culture can have a significant impact on the establishment of the Baekje cultural identity and the competitiveness of the region.

• 보존과학연구
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• s.26
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• pp.127-139
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• 2005

We have conserved the sword with round pommel with a tri-ring which was excavated from No. 1 tomb of the Duckcheon-ri at the Gyeongju and requested from Jungang Research Center of the Cultural Heritage. When this artifact excavated, it was pressed flat state because of the influence of earth pressure and stuck to a gravel and soil laid scattered on the wooden coffin. If the artifacts is handled without plan, it can be damaged, therefore that sword was collected together with soil using the Polyurethane foam. After the artifact which had a weak specific and was collected using a this method can be safetly collected as below; First, we made the supporter of article ordered using a silicon and gypsum. The silicon can conserve the weak point of the artifact because it has a flexible and smooth properties and the gypsum can adhere closely to the artifact because it has a little expansion and shrinking but a hard and fluid characters. Consequently, gypsum is a good complement to the weak point of the silicon. Second, During a remove gauze and a reinforcing agent from the surface of a artifact which was reinforced using a acetone steam method. The acetone steam method can be supplement to a dangerous problem of acetonedircet method because this can be damaged in a surface of the artifact.