• 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 the Korean Society of Safety
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• v.38 no.5
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• pp.8-14
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• 2023

Lithium ions can induce the thermal runaway phenomenon and lead to reignition due to electrical, mechanical, and environmental factors such as high temperature, smoke generation, explosions, or flames, which is extremely likely to create safety concerns. Therefore, one of the ways to improve the flame retardancy of the electrolyte is to use a flame-retardant additive. Comparing the associated characteristic value of existing substances with the required experimental value, it was found that these values were either considerably different or were not documented. It is vital to know a substance's combustion characteristic values, flash point, explosion limit, and autoignition temperature (AIT) as well as its combustion characteristics before using it. In this research, the flash point and AIT of materials were measured by mixing a highly volatile and flammable substance, diethyl carbonate (DEC), with flame-retardant dimethyl methylphosphonate (DMMP). The flash point of DEC, which is a pure substance, was 29℃, and that for DMMP was 65℃. Further, the lower explosion limit calculated using the measured flash point of DEC was 1.79 Vol.%, while that for DMMP was 0.79 Vol.%. The AIT was 410℃ and 390℃ for DEC and DMMP, respectively. In particular, since the AIT of DMMP has not been discussed in any previous study, it is necessary to ensure safety through experimental values. In this study, the experimental and regression analysis revealed that the average absolute deviation (ADD) for the flash point of the DEC+DMMP DEC+DMMP system is 0.58 sec and that the flash point tends to increase according to changes in the composition employed. It also revealed that the AAD for the AIT of the mixture was 3.17 sec and that the AIT tended to decrease and then increase based on changes in the composition.

• Journal of the Korean GEO-environmental Society
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• v.16 no.4
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• pp.13-22
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• 2015

The combined impact of Dissolved Organic Matter (DOM) fouling and inorganic ($CaSO_4,Ca_3(PO_4)_2$) scaling on the retention of TNT (2, 4, 6-Trinitrotoluene), RDX (Hexahydro-1, 3, 5-trinitro-1, 3, 5-triazine) and HMX (1, 3, 5, 7-Tetranitro-1, 3, 5, 7-tetrazocane) explosive contaminants by nano-filtration membrane were studied, since organic fouling and salt scaling are the major limitations for membrane filtration. Results reported here indicate that DOM fouling layer with a humic acid does not necessarily lead to an immediate loss of permeate flux but can result in a severe impact on the flux loss when both humic acid and inorganic scaltants were presented simultaneously. The $Ca_3(PO_4)_2$ mixed with humic acid showd most sever flux loss (42%) compared to that of only humic acid presence (8%). It could be a result that the scaling formation of the NF membrane was dominated by cake layer formation of DOM and it was along with pore blocking by the formation of crystals inside the porous active matrix of the NF membrane. In addition, these results indicated that the membrane selectivity of the explosives retention trended correlated with respect to increasing explosives size (listed by MW) based on greater steric interactions and followed the order (MW, g $mol^{-1}$; removal, %): HMX (296.15; 83%) ${\gg}$ RDX (222.12; 49%) ≋ TNT (227.13; 32%). Because the scaling and fouling layer could lead to a additional cake-enhanced concentration polarisation effect, the retention of explosives with the presence of humic acid in the feed solution and inorganic scaling formation on top of an organic fouling layer do not differ substantially retention from that of pure DI feed and NaCl solution.

• Journal of the Daesoon Academy of Sciences
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• v.39
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• pp.215-247
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• 2021

In Buddhism, there are specific terms related to miracles and miraculous acts such as the Sanskrit term, abhijñā, which was translated as into Chinese characters as shintong (神通). This term implies the six supranormal powers. It originally meant 'direct knowledge,' 'high knowledge,' or 'knowledge beyond the common senses,' which was understood as a superhuman and transcendental ability possessed by Buddhas, Bodhisattvas, and noblemen. However, this took on different meanings and morphed into different terms later in India and China. This article analyzes the subject, object, type, and purpose of these shintong, focusing on the Sutra for the Householder Kaivarti (堅固經, Gyeonggo-gyeong, Kaivarti-sūtra) from the Longer Discourses (長阿含經, Jang-Ahamgyeong, Dīrghâgama) and exemplary Buddhist texts such as the Sanskrit, In Praise of the Acts of the Buddha (佛所行讚, Bulsohaengchan, Buddhacaritam) and the Chinese Records of Eminent Monks (高僧傳, goseungjeon) and Continued Records of Eminent Monks (續高僧傳, Sok-goseungjeon). The historical evolution and changes to the meaning of Shintong in Indian and Chinese contexts can be observed through these texts. In the Sutra for the Householder Kaivarti, the Buddha said that there are three kinds of Shintong: supranormal footedness (神足, shinjok, ṛddhi-pāda), mindreading (觀察他心, gwanchaltashim, anya-mano-jñāna), and education (敎誡, gyogye, anuśāsana). Among them, supranormal footedness (multiplying one's body, teleportation, flying, walking on water, etc.) and mindreading were denied because, at that time, claims of this nature were used to appeal to people's emotions and inspire sincerity, but this was of no use in conveying the Buddha's teaching. On the other hand, education, acquired only with through enlightenment, was sanctioned as a shintong unique to Buddhism. However, in In Praise of the Acts of the Buddha, supranormal footedness and mindreading were described as important ways to lead people to enlightenment, while education pertained to the whole of spiritual work. In China, Buddhism was a foreign religion at first, and it urgently sought to be accepted. After the increase of its religious influence, introspection on discipline and practice was meant to firmly deepen its roots. In line with this, shintong and miracles were transformed and expanded to suit the Chinese cultural context. Such changes in Buddhist history are well illustrated by the shini (神異, miraculous powers) described in Records of Eminent Monks and the gamtong (感通, penetration of sensitivity) detailed in Continued Records of Eminent Monks. In Records of Eminent Monks, the subject of shini was that of eminent monks and its objects were those who did not know of Buddhism or believe in it. In Continued Records of Eminent Monks, however, the monks themselves could be objects of shini. The change of object suggests that the purpose had shifted from edification to awareness and self-reflection. Shini focused on edification, whereas gamtong re-emphasized the importance of the pure discipline and practice of monks during the 6^th and 7^th centuries when China became predominantly Buddhist.