• Proceedings of the KWS Conference
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• 2005.06a
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• pp.152-154
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• 2005

Austenitic stainless steel has good weldability but is sensitive to hot cracking such as solidification crack and liquation crack. In this study, the specimens of dissimilar metals made between austenitic stainless steel and Al-brass were welded by GTAW process using four different filler metals. Cracks were detected in the heat-affected zone of the stainless steel when welded with CuAl, CuSn and NiCu filler metals, but no cracks were detected a Ni filler metal was used. The cracks propagated along the grain boundary in the heat affected zone near the fusion line to base metal of 316L stainless steel. The cracks were located inside the weld bead with very fine hairline crack. All cracks initiated at the fusion line and moved forward in the base metal. From energy dispersion spectroscopy (EDS), Cu peak was detected only in the crack-opening area.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.36 no.4
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• pp.92-99
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• 2013

Many automotive components for power generation such as motors and alternators have been widely using ferrite magnets. To ensure a high level of efficiency could be achieved in an alternator, the assembled magnets must be in good enough durability. Recently, some hairline cracks have been found on the magnet produced by manufacturers in Korea. Thus, there is an increasing concern that some of the magnets produced could cause further problems after being assembled in the alternator. Based on the standard alternator test (RS0008 : 2006), this paper has developed an accelerated failure-free test for magnets in alternator to demonstrate that assembled magnets will meet durability objective specified by the manufacturer. This guarantees the target life of the magnet with 90 percent reliability and 90 percent confidence level (R90C90). Temperature and rotation speed were selected as accelerated stress factors.

• Journal of the Korean Society of Costume
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• v.57 no.5 s.114
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• pp.151-165
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• 2007

Appearance matters in society today. Women want to feel good and look their best. They do make-up, wear garment and accessory for their good looking. Doing make-up, we have to know how we are look and to consider face shape. But it is difficult to recognize face shape. Because there is no standard face shape of adult women of quantitative analysis. The purpose of this study was to offer standard face shape of adult women in Korea. Furthermore, the study was to determine and differentiate face shape of each age group to set the basic data for the Korean beauty industry. In this study, photographs of 600 Korean women, age between $20{\sim}50's$, were indirectly measured in Venus face2D program. The measurements were analyzed by statistical methods. As a result of basic statistical data analysis, the average lengths of face were 196mm, lengths of forehead-hairline between eyebrows were 62mm, lengths of eyebrow between noses were 68mm, length of nose between chin were 66mm, and width of face were 150mm. By comparing to each age group's face using ANOVA, the statistically noticeable differences were found in measurements.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.12
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• pp.2909-2916
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• 2000

6.5wt% Si steel is widely known as an excellent magnetic material because its magnetostriction is nearly zero. The AX magnetic properties as magnetostriction of 6.5% Si steel were evaluated and compared with those of conventional 3% Si steel sheet. In this paper, the fracture behavior of the poly crystals and single crystals of Fe-6.5wt%Si alloy has been observed. Single crystals were prepared by Floating Zone(FZ) method, which melts the alloy by the use of high temperature electron beam in pure argon gas condition. And the single crystals were annealed at 500$^{\circ}C$ and 700$^{\circ}C$ respectively and tensile tested at room temperature. According to the result, B2 phase has more good elongation than DO$_3$ phase. It was also found that the fracture surfaces of the single crystals have hairline facets in same direction, and the facets change the direction according to the single crystal phase.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.816-823
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• 2007

Electric car tract plays the role of supply high electric power to the electric car from the substation by using Pantograph of the electric car. It is always exposed to the external atmosphere, which results in quite substantial fluctuations in current and voltage during operation of electric car. This generates possibility of occurrence of accident at all times. Since range of wiring metallic globe installed on the catenary cannot achieve complete electrical contact, accidents are occurring due to circulating current caused by arc caused by incomplete contact due to occurrence of hairline fracture of Pantograph due to pressure or vibration of wiring. Furthermore, rapid increase in the operational current due to increase in the operational frequency of the electric car is causing erosion and short circuit of the metallic globe at the contact points. This study on arc is generated as current transmitted out of the substation courses through power line or wiring metallic globe other than the main circuit as the current is being collected at the electric car through feeder and feeder divergence device. Accordingly, since heat generated by the arc becomes the cause for generation of circulating current due to melting of metal or softening of metal due to increase in temperature accompanying increase in contact resistance, this research shall describe causes and measures against occurrence of circulation current.

• Archives of Plastic Surgery
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• v.42 no.5
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• pp.580-587
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• 2015

Background Descent of the lateral aspect of the brow is one of the earliest signs of aging. The purpose of this study was to describe an open surgical technique for lateral brow lifts, with the goal of achieving reliable, predictable, and long-lasting results. Methods An incision was made behind and parallel to the temporal hairline, and then extended deeper through the temporoparietal fascia to the level of the deep temporal fascia. Dissection was continued anteriorly on the surface of the deep temporal fascia and subperiosteally beyond the temporal crest, to the level of the superolateral orbital rim. Fixation of the lateral brow and tightening of the orbicularis oculi muscle was achieved with the placement of sutures that secured the tissue directly to the galea aponeurotica on the lateral aspect of the incision. An additional fixation was made between the temporoparietal fascia and the deep temporal fascia, as well as between the temporoparietal fascia and the galea aponeurotica. The excess skin in the temporal area was excised and the incision was closed. Results A total of 519 patients were included in the study. Satisfactory lateral brow elevation was obtained in most of the patients (94.41%). The following complications were observed: total relapse (n=8), partial relapse (n=21), neurapraxia of the frontal branch of the facial nerve (n=5), and limited alopecia in the temporal incision (n=9). Conclusions We consider this approach to be a safe and effective procedure, with long-lasting results.

• Journal of the Korea Concrete Institute
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• v.17 no.6 s.90
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• pp.1053-1064
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• 2005

The mechanical damage of concrete is normally attributed to the formation of microcracks and their propagation and coalescence into macroscopic cracks. This physical degradation is caused from progressive and hierarchical damage of the microstructure due to debonding and slip along bimaterial interfaces at the mesoscale. Their growth and coalescence leads to initiation of hairline discrete cracks at the mesoscale. Eventually, single or multiple major discrete cracks develop at the macroscale. In this paper, from this conceptual model of mechanical damage in concrete, the computational efforts were made in order to characterize physical cracks and how to quantify the damage of concrete materials within the laws of thermodynamics with the aid of interface element in traditional finite element methodology. One dimensional effective traction/jump constitutive interface law is introduced in order to accommodate the normal opening and tangential slips on the interfaces between different materials(adhesion) or similar materials(cohesion) in two and three dimensional problems. Mode I failure and mixed mode failure of various geometries and boundary conditions are discussed in the sense of crack propagation and their spent of fracture energy under monotonic displacement control.

• Archives of Craniofacial Surgery
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• v.18 no.4
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• pp.273-276
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• 2017

Osteomas are benign, slow-growing tumors that most frequently occur in the craniomaxillofacial region. These tumors are mostly asymptomatic and are generally found incidentally. A giant osteoma is generally considered to be greater than 30 mm in diameter or 110 g in weight. A 35-year-old female presented to us with complaints of a firm mass that showed continuous growth on the forehead following trauma. A hairline incision was made to expose the osteoma. Biopsy of the tumor confirmed a osteoma. There were no complications after surgery. Postoperative computed tomography revealed that the tumor was completely removed. Because a peripheral giant osteoma of the frontal bone with a history of trauma is a rare finding, thorough history-taking, physical examination, and preoperative imaging tests are needed for patients with a history of trauma to rule out a giant osteoma.

• Steel and Composite Structures
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• v.39 no.3
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• pp.307-318
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• 2021

Utilizing fibers is an effective way to avoid the brittle behavior of the conventional concrete and can enhance its ductility. In particular, propylene fibers can improve concrete properties, including energy absorption, physical and mechanical properties, controlling shrinkage cracks. The increase of fiber density leads to an increase of the overlapping surface of the fiber of concrete and, in turn, a decrease of cracks developed in the concrete. However, the workability of fiber reinforced concrete tends to be lower than the conventional concrete owing mainly to the hairline thickness and excessive concentration of fibers. The low slump of concrete impedes the construction of reinforced concrete members. In this research, we study if the utilization of magnetic water can alleviate the workability issue of young fiber reinforced concrete. To this end, the compressive and flexural strength of four types of concrete (conventional concrete, fiber reinforced concrete, magnetic concrete, magnetic fiber-reinforced concrete) is studied and compared at three different ages of 7, 14, and 28 days. In order to study the influence of the fiber density and length, a study on specimens with three different fiber density (1, 2, 5 kg of fiber in each cubic meter of concrete) and fiber length (6, 12, 18 mm) is undertaken. The result shows the magnetic fiber concrete can result in an increase of the flexural and compressive strength of concrete at higher ages.

• Archives of Craniofacial Surgery
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• v.22 no.3
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• pp.157-160
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• 2021

Head and neck cutaneous metastasis of advanced gastric cancer is uncommon, and scalp metastasis is particularly rare. We present the case of a 60-year-old man who was diagnosed with cutaneous metastasis on the scalp originating from advanced gastric cancer. The patient was referred to the plastic surgery department for a scalp mass near the hairline. He had been diagnosed with advanced gastric cancer and undergone total gastrectomy and Roux esophagojejunostomy 3 years previously. The differential diagnosis for a single flesh-colored nodule on the scalp included benign tumors such as epidermal cyst or lipoma; therefore, the patient underwent excision and biopsy. In the operative field, the mass was found to be located in the frontalis muscle. The biopsy result showed that the mass was a metastatic lesion of advanced gastric cancer. Whole-body computed tomography revealed a gastric tumor with blood vessel infiltration, peritoneal carcinomatosis, liver metastasis, and multiple disseminated subcutaneous metastases. Although scalp metastasis originating from an internal organ is extremely rare, plastic surgeons should always consider a metastatic lesion in the differential diagnosis if a patient with a scalp lesion has a history of malignant cancer.