• The Pure and Applied Mathematics
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• v.29 no.4
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• pp.277-291
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• 2022

The aim of this article is to examine some types of slant submanifolds of bronze Riemannian manifolds. We introduce hemi-slant submanifolds of a bronze Riemannian manifold. We obtain integrability conditions for the distribution involved in quasi hemi-slant submanifold of a bronze Riemannian manifold. Also, we give some examples about this type submanifolds.

• Journal of Advanced Marine Engineering and Technology
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• v.22 no.1
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• pp.67-76
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• 1998

Friction materials for brake linings and clutches have severe performance requirements. The principal function of such frictional elements is to convert kinetic energy to heat, and then either to absorb or to dissipate heat. In order to achieve these objectives, the coefficient of friction must be as high as possible, independent of variations in operating conditions, and the necessary energy conversion must be accomplished with a minimum of wear on the contacting parts. In this study, Al powder, Al bronze powder and Mo powder used in general for automobile brake was sprayed on automobile brake disc to restrain rust and to maintain friction performance. Dynamo and corrosion tests have been carried out. It is concluded that the sprayed disc with Al bronze powder has the most improved frictional performance and anti-corrosive characteristics. The main results obtained can be summarized as follows; 1. From the corrosion current density test for gray cast iron and sprayed disc with powders of Al, Al bronze and Mo, it was cleared that the spray treatment with Al bronze powder showed the most superior anti-corrosive characteristics than other powders. 2. By anode polarization toward the noble direction from corrosion potential, corrosion current density with sprayed brake disc by Al-bronze powder was the lowest. 3. Mean frictional coefficients obtained from dynamo test are as follows : the sprayed disc with Al(99.99%) powder was 0.190 ; the sprayed disc with Al-bronze powder was 0.312 ; the sprayed disc with Mo powder was 0.257 ; the non-sprayed disc of gray cast iron was 0.331. In the case of the sprayed disc Al-bronze powder showed the most excellent frictional characteristics . 4. Amount of burnish quantity obtained from burnish test by dynamometer is as follows : the sprayed disc with Al-powder was 1.079 mm : the sprayed disc with Al-bronze powder was 0.155 mm : the sprayed disc with Mo powder was 0.253 mm : the non-sprayed disc of gray cast iron was 0.241 mm. Al-bronze powder also showed the most excellent burnish characteristics.

• Journal of the Korean institute of surface engineering
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• v.41 no.6
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• pp.255-263
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• 2008

Generally, deposition mechanism of diamond particle is mainly embedding effect in the kinetic spray process. Accordingly, in spite of high cost, helium gas was employed as process gas to get high diamond fraction in the composite coating. In this study, the deposition behavior of bronze/diamond by kinetic spray process was compared using different process gas (helium and nitrogen). Bare (mean size of $5{\mu}m$, $20{\mu}m$) and nickel coated diamond (mean size of $26{\mu}m$) were deposited on Al 6061-T6 substrate with fixed process temperature and pressure. For comparison with experimental results, plastic deformation behavior of nickel layer was simulated by finite element analysis (using ABAQUS/Explicit 6.7-2). The size, broken ratio, and fraction of diamond in the composite coating were analyzed through scanning electron microscopy and image analysis method. The uniform distribution and deposition efficiency of diamond particles in the coating layer could be achieved by tailoring the physical properties of the feedstock.

• Korean Journal of Heritage: History & Science
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• v.56 no.1
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• pp.100-116
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• 2023

The Sinamsa Temple was built in the late Goryeo Dynasty and a gilt-bronze seated Buddha is enshrined in Geungnakjeon hall in the precinct. Various damages occurred in the gilt layer of the Buddha, such as peeling of the gilt layer and deteriorating gloss. In the study, the conservation conditions of the inside and outside on the statue were accurately investigated, and the making technique was interpreted through the material characteristics and non-destructive diagnosis of the statue. As a result, it is estimated that gold-gilding layer is pure gold, coloration pigment of black is carbon, green is malachite, atacamite and verdigris, red is red lead and cinnabar, respectively. In the deterioration evaluation, peeling, cracking, break out and exfoliation of the gilt layer are confirmed as damages, but the conservation condition is relatively wholesome. However, the gloss of the gilt layer is calculated to be wider in the poorer part than the maintenance part. The ultrasonic velocity of the statue was calculated to be 1,230 to 3,987 (mean 2,608) m/s and showed a relatively wide range. In infrared thermography, peeling was not confirmed, and no special bonding marks were found. In endoscope, some biological damage and corrosion were observed on the surface of the internal metal, and sealed artifacts were identified. Manufacturing technique based on the study, it is considered that the gilt-bronze seated Buddha was cast at once, and the mold was inverted to inject molten metal.

• Journal of Conservation Science
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• v.8 no.1 s.11
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• pp.16-22
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• 1999

Species of 741 charcoal samples, which were excavated from the dwelling sites of the bronze age $(about\;2500\~3100\;B.P)$ at Hyeonwha-ri, Pyungteak, Korea, were identified. Most of samples were deciduous oaks (Quercus spp.; $97.7\%$) and others were alders (Ainus spp.; $1.9\%$) and soft pines (Pinus spp.; $0.4\%$). Tree rings of nine largest samples were also examined. The numbers of annual rings were 8 to 36 and mean ring width was rather narrow $(0.65\~1.82\;mm)$. Most samples possessed pith and tylosis. The results indicate that logs 10 to IS cm diameter had been used for the poles of houses without further processing.

• Korean Journal of Heritage: History & Science
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• v.38
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• pp.387-419
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• 2005

Material characteristics and provenance interpretation of the raw materials for the stone moulds of bronze artifacts excavated in Galdong Prehistoric site were studied. The stone moulds are made of igneous hornblendite with coarse-grained holocrystalline textures. The surface color shows greenish grey to dark green with greasy luster. The value of magnetic susceptibility of the moulds ranges from 19.2 to 71.0 (mean ; $39.2{\times}10^{-3}$ SI unit).High value of magnetic susceptibility indicates high contents of magnetite as a ferromagnetic mineral and the wide range of the values are due to heterogeneous distribution of magnetite. These are characteristics of basic igneous rocks. The rock-forming minerals of the moulds mainly consist of amphibole, plagioclase and biotite. Pyroxene, chlorite and opaque minerals are also rarely present. A large quantity of carbon was detected on the dark black crust near the surface of the moulds by quantitative analysis. Geological field survey was carried out to identify a source of the raw materials of the stone moulds around Galdong site. Hornblendite or gabbroic rocks being similar to the moulds forming rock occur at Daeseongri, Sikcheonri and Gyodongri in Jangsoo, and Illdaeri in Namwon about 50 kilometers away from the site in a straight line. They have similarity with the moulds forming rock in magnetic susceptibility ranging from 16.1 to 72.4 (mean ; $39.9{\times}10^{-3}$ SI unit). Among those hornblendite or gabbroic rocks, one in Jangsoo area is the most similar to the moulds forming rock on the basis of petrological and mineralogical characteristics. Comparing normalized patterns of major, minor, rare earth and immobile elements contents of the moulds to them of hornblendite in Jangsoo area, geochemical evolution trend and behavior characteristics show affinities between them. It suggests that the moulds forming rock and hornblendite in Jangsoo area have been originated from cogenetic magma. This hornblendite is easy to engrave an inscription or detail graphics on the surface because of its softness, and has good thermal conductivity. Hornblendite in Sikcheonri, Jangsoo is particularly produced and used for stone wares until the present day. Therefore, it is probable that the stone materials of the moulds has been imported from Daeseongri, Sikcheonri and Gyodongri in Jangsoo area. However, it cannot be completely excluded the possibility that the material of the moulds was supplied from Illdaeri in Namwon area appearing the same type of hornblendite on a small outcrops. It is necessary to carry out further archaeological studies to identify several possibilities of migration process of raw materials.

• Sim-seong Yeon-gu
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• v.29 no.1
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• pp.1-45
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• 2014

Mystic experience such as seeing an vision could be explained as experiencing elusive and mysterious unique existence in religious way. In depth psychology, which is based on unconsciousness like analytical psychology, this could be explained as a something that gives a meaning of life and purpose through discovering health and healing. The importance of primodial experience in depth psychology is that it can possibly discover the base of present acts. In Christian theology, symbolic mystery and truth of religious experience that appear in Christian tradition have interest on human situation. These two fields' approach methods are different, but both show common interest on unique experience which can be said properly as raw experience. Various visions appear in many parts of the Bible. Among many visions, the book of Zechariah, one of the 12 Prophets, describes rich and diverse 8 visions through chapter 1 to chapter 8. However, due to the Genre of revelation, it lacks historicity, and because of vagueness and symbolic meanings, its visions are hard to understand and interpret. Theologically, visions of Zechariah show communality of Israelites by reconstructing kingdom of Judah and church in a way of historical circumstances. Though, these visions could deliver the meaning of an ethnical aspect as reporting continuous conversation between the God and humans. Furthermore, it could mean a personal aspect of the Prophet Zechariah as reaching for a opportunity of new change. Moreover, those who read these visions could try to interpret the meanings of various images which represent meeting mysterious existences. Therefore, the Author would concentrate on the fact that 8 visions in the book of Zechariah, which has not been received much attention to neither Christians nor non-believers, develop in chiastic structure (stylistic contrast), so that tries to interpret the first, second, seventh, and the eighth visions in analytic psychology way. In visions of Zechariah, excepting the 4th vision which probably was inserted later, rest of 7 visions each shows the stage of the hours of darkness. 1st to 3rd visions represent evening, 5th vision represents deep in the night, and 6th to 8th visions represent dawn to morning. Moreover, since structure of visions arranged in chiastic way, horse appears in 1st and 8th vision, measuring rope and measure tools are used as main motif in 2nd and 7th vision. However, same motifs could have different symbolic meanings and roles as visions are formed in different situations and conditions. In the first vision, angels who ride horses look around the world and report it is calm and peaceful. Concerning the political situation back in the day, the world being calm and peaceful in the beginning of evening means that it is not ready to change to a whole new world. Psychologically, if there is no readiness to adopt new world, it means being hopeless. It is sending you a message to get out of those kinds of situation. Moreover, appearance of four angels who rode red, brown, and white horses to a myrtus tree in the valley means that it is time for individuation and it is right and good timing for changing. In second vision, you will be able to see that Israelites had long years being caught in the shadows by foreign country, and long years succumbed by the strength of four horns, which shows the progress of renewing strength and being oneness with oneself from overwhelmed situation by paternity. In seventh vision, meaning of two women bringing the godness of the sky, who were locked up in a rice basket, back to the temple in Babylon is going towards in a level of Self-actualization by separating one's ego captured excessively by matherhood and putting back to a place where it was before. In eighth vision, chariots pulled by horses are scattered far and wide, and horses which went to north had rest in the land of North. After horses and chariots are seen between two mountains of bronze with the image of Self and anima/animus. These images can be explained as the changing progress are almost completed and the God and human, in other words Self and ego are being united and is now time for rest. All of 8 visions contains the conversation between angel and Zechariah who willing to know the meaning of visions. Zechariah asks the angel actively about the meaning of visions because of his wish for Israelites to return home and rebuild church. Conversation among the God, Zechariah, who asks questions until he knows everything, an Angel, who gives answer to given questions, is conversation between ego and anima/animus. Eventually, it is a conversation between Self and ego.