• Journal of the Korean Wood Science and Technology
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• v.43 no.6
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• pp.868-875
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• 2015

In order to replace existing slit type steel plate on the wooden structure joint, the FRP-reinforced laminated plates were produced. Four types of FRP-reinforced laminated plates were produced according to the type of reinforcement and adhesive, and before applying to the joint, the adhesion performance test according to KSF 3021 and KSF 2160 and the Compact Tension (CT) type fracture toughness test specified in ASTM D5045-99 were carried out. As a result of adhesion performance test, all GFRP textile, GFRP sheet, and GFRP Textile-Sheet type FRP-reinforced laminated plates satisfied the requirement of soaking delamination percentage with smaller than 5% based on KS standard. However, aramid type specimen satisfied the standard as the soaking delamination percentage of 4.8% but it did not satisfied the standard as the water proof soaking delamination percentage of 70%. As a result of fracture toughness test, the volume ratio of reinforcement to timber became 23% so that the strength of FRP-reinforced laminated plates increased by two to four times in comparison to the control specimen. It was confirmed that the GFRP Textile-Sheet type specimen was most resistant to the fracture most since the ratio of stress intensity factor compared with that of the control increased to 61% owing to the parallel arrangement of glass fiber to the load. As a result of tensile shear strength test using FRP-reinforced laminated plates and nonmetal dowels, it is about 12% lower than metal connectors.

• Journal of the Korea Institute of Building Construction
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• v.13 no.2
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• pp.122-130
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• 2013

One of recent methods to protect wooden cultural assets from fire, there is the flame retardation which is applied directly to wood and it is to prevent fire through securing flame resistance for the material and delaying combustion when failed fire in advance and then to gain time for people in the room to evacuate and it has same goal with the Korean Fire Service Act by protecting life and property. However, in case of spraying flame retardant on the colored surface of the wooden cultural assets, there are continuous problems of decoloration, efflorescence and water absorbtion after sometime and accordingly there increases danger of damages of cultural assets. So when treating with flame retardant on wooden cultural assets, there has to be no problems on dancheong after sometime and securing sustainable methods for flmae retardation should be preceded. Accordingly, this study aims to provide basic sources for selecting proper flame retardation methods by evaluating and analyzing flame retardation capabilities according to types of flame retardants which are frequently used nowadays and spraying them on the dancheong-painted surface and confirming if there is no problem on the dancheong and wood after sometime and if flame retardation effect is sustainable with its quality and capability through precise analysis.

• Polymer(Korea)
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• v.36 no.2
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• pp.177-181
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• 2012

This study presents the preparation of double emulsions in a poly(dimethylsiloxane) (PDMS)-based microfluidic device. To improve the wettability of hydrophilic continuous phase onto a hydrophobic PDMS microchannel, the surface was modified with 3-(trimethoxysilyl) propyl methacrylate (TPM) and then sequentially reacted with acrylic acid monomer solution, which produced selective covalent bonding between acrylic acids and methacrylate groups. For the proof of selective surface modification, tolonium chloride solution was used to identify the modified region and we confirmed that the approach was successfully performed. When water containing 0.5% w/w sodium dodecyl sulfate and 1% w/w Span80 with hexadecane were loaded into the selectively modified microfluidic channels, we can produce stable double emulsion. Based on the spreading coefficients, we predict the morphology of double emulsions. Our proposed method efficiently produces monodisperse double emulsions having 48.5 ${\mu}m$(CV:1.6%) core and 65.1 ${\mu}m$ (CV:1.6%) shell. Furthermore, the multiple emulsions having different numbers of core were easily prepared by simple control of flow rates.

• Nutrition Research and Practice
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• v.17 no.2
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• pp.371-385
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• 2023

BACKGROUND/OBJECTIVES: Soy isoflavone (SIF) and soy lecithin (SL) have beneficial effects on many chronic diseases, including neurodegenerative diseases. Regretfully, there is little evidence to show the combined effects of these soy extractives on the impairment of cognition and abnormal cerebral blood flow (CBF). This study examined the optimal combination dose of SIF + SL to provide evidence for improving CBF and protecting cerebrovascular endothelial cells. MATERIALS/METHODS: In vivo study, SIF50 + SL40, SIF50 + SL80 and SIF50 + SL160 groups were obtained. Morris water maze, laser speckle contrast imaging (LSCI), and hematoxylin-eosin staining were used to detect learning and memory impairment, CBF, and damage to the cerebrovascular tissue in rat. The 8-hydroxy-2'-deoxyguanosine (8-OHdG) and the oxidized glutathione (GSSG) were detected. The anti-oxidative damage index of superoxide dismutase (SOD) and glutathione (GSH) in the serum of an animal model was also tested. In vitro study, an immortalized mouse brain endothelial cell line (bEND.3 cells) was used to confirm the cerebrovascular endothelial cell protection of SIF + SL. In this study, 50 µM of Gen were used, while the 25, 50, or 100 µM of SL for different incubation times were selected first. The intracellular levels of 8-OHdG, SOD, GSH, and GSSG were also detected in the cells. RESULTS: In vivo study, SIF + SL could increase the target crossing times significantly and shorten the total swimming distance of rats. The CBF in the rats of the SIF50 + SL40 group and SIF50 + SL160 group was enhanced. Pathological changes, such as attenuation of the endothelium in cerebral vessels were much less in the SIF50 + SL40 group and SIF50 + SL160 group. The 8-OHdG was reduced in the SIF50 + SL40 group. The GSSG showed a significant decrease in all SIF + SL pretreatment groups, but the GSH showed an opposite result. SOD was upregulated by SIF + SL pretreatment. Different combinations of Genistein (Gen)+SL, the secondary proof of health benefits found in vivo study, showed they have effective anti-oxidation and less side reaction on protecting cerebrovascular endothelial cell. SIF50 + SL40 in rats experiment and Gen50 + SL25 in cell test were the optimum joint doses on alleviating cognitive impairment and regulating CBF through protecting cerebrovascular tissue by its antioxidant activity. CONCLUSIONS: SIF+SL could significantly prevent cognitive defect induced by β-Amyloid through regulating CBF. This kind of effect might be attributed to its antioxidant activity on protecting cerebral vessels.

• The Journal of Engineering Geology
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• v.7 no.3
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• pp.191-205
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• 1997

Measurements on subsurface movement of the Songsanri tomb site including the Muryong royal tomb was conducted using a tiltmeter system for the period of 15 months form July 7, 1996 to September 30, 1997. Two coordinate tilt monitoring data shows the biggest movement rate of 2.3mm/m/yr toward south in the frontal wall(N-S tilt) of the Muryong royal tomb. Southward tilting of bricks above the southern fire place in the western wall of the Muryong royal tomb is a proof of southward tilting of the royal tomb since its excavation in 1971. The eastern wall of the Muryong royal tomb is also tilting toward inside the tomb with the rate of 1.523mm/m/yr. Furthermore, tilting rate of wall increases twice in rainy season. It is interpreted tbat infiltration of water into the tomb and nearby ground in rainy season results in dangerous status for the safety of tomb structure. On the whole, normal component tilting of the walls of the 5th tomb is large than its shear component. It shows a small displacement toward one direction without no abrupt change in its direction and amount of tilting. The tilting rate of walls of the 6th tomb is about 8.8mm/m/yr in the dry season which is much bigger than those of other tombs in rainy season. Deformation events of walls of the tombs are closely related to amount of precipitation and variation of temperature. In comparison with different weather conditions, tilting is much bigger during the period of rainy weather than sunny weather. It is interpreted that rainwater flew into the turm through faults and nearby ground. High water content in nearby ground resulted strength of ground. The tilting event of walls shows a hysterisis phenomenon in analysis of temperature effect on tilting event. The walls tilt rapidly with steep rising of temperature, but the tilted walls do not come back to original position with temperature falling. Therefore, a factor of steep increase of the temperature must be removed. It means the tomb have to be kept with constant temperature. The observation of groundwater level using three boreholes located in construction site and original ground represented that groundwater level in construction site is higher than that of original ground during the rainy season from the end of June to August. It means that the drainage system of the Muryong royal tomb is worse than original ground, and it is interpreted that the poor drainage system is related to safety of tomb structure. As above mentioned, it is interpreted that artificial changes of the tomb environment since the excavation, infiltration of rainwater and groundwater into the tomb site and poor drainage system had resulted in dangerous situation for the tomb structure. According to the result of the long period observation for the tomb site, it is interpreted that protection of the tomb site from high water content should be carried out at first, and the rise of temperature by means of the dehumidifier inside the tomb must be removed.

• Journal of the Korean Geosynthetics Society
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• v.16 no.4
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• pp.231-240
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• 2017

Recently, there have been frequent occurrences of ground sink in the urban area, which have resulted in human and material damage and are accompanied by economic losses. This is caused by artificial factors such as soil loss, poor compaction, horizontal excavation due to the breakage of the aged sewage pipe, and lack of water proof at vertical excavation. The ground sink can be prevented by preliminary restoration and reinforcement through exploration, but it can be considered that it is not suitable for urgent restoration by the existing method. In this study, a model experiment was carried out to simulate the in-ground cavities caused by groundwater flow for developing non-excavation urgent restoration in underground cavity and the range of the relaxation zone was estimated by detecting the around the cavity using a relaxation zone detector. In addition, disturbance region and relaxation region were separated by injecting gypsum into cavity formed in simulated ground. The shape of the underground cavity due to the groundwater flow was similar to that of the failure mode III formed in the dense relative density ground due to water pipe breakage in the previous study. It was confirmed that the relaxed region detected using the relaxation zone detector is formed in an arch shape in the cavity top. The length ratio of the relaxation region to the disturbance region in the upper part of the cavity center is 2: 1, and it can be distinguished by the difference in the decrease of the shear resistance against the external force. In other words, it was confirmed that the secondary damage should not occur in consideration of the expandability of the material used as the injecting material in the pre-repair and reinforcement, and various ground deformation states will be additionally performed through additional experiments.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.20 no.1
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• pp.49-59
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• 1984

Optimizing investigation of characteristics of underwater welding by a gravity type arc welding process was experimentally carried out by using six types of domestic coated welding electrodes for welding of domestic marine structural steel plates (KR Grade A-1, SWS41A, SWS41B,) in order to develop the underwater welding techniques in practical use. Main results obtained are summarized as follows: 1. The absorption speed of the coating of domestic coated lime titania type welding-electrode became constant at about 60 minutes in water and it was about 0.18%/min during initial 8 minutes of absorption time. 2. Thus, the immediate welding electrode could be used in underwater welding for such a short time in comparison with the joint strength of in-atmosphere-and on-water-welding by dry-, wet-or immediate-welding-electrode. 3. By bead appearance and X-ray inspection, ilmenite, limetitania and high titanium oxide types of electrodes were found better for underwater-welding of 10 mm KR Grade A-1 steel plates, while proper welding angle, current and electrode diameter were 6$0^{\circ}C$, above 160A and 4mm respectively under 28cm/min of welding speed. 4. The weld metal tensile strength or proof stress of underwater-welded-joints has a quadratic relationship with the heat input, and the optimal heat input zone is about 13 to 15KJ/cm for 10mm SWS41A steel plates, resulting from consideration upon both joint efficiency of above-100% and recovery of impact strength and strain. Meanwhile, the optimal heat input zone resulting from tension-tension fatigue limit above the base metal's of SWS41A plates is 16 to 19KJ/cm. Reliability of all the empirical equations reveals 95% confidence level. 6. The microstructure of the underwater welds of SES41A welded in such a zone has no weld defects such as hydrogen brittleness with supreme high hardness, since the HAZ-bond boundary area adjacent to both surface and base metal has only Hv400 max with the microstructure of fine martensite, bainite, pearlite and small amount of ferrite.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.30 no.2
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• pp.142-154
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• 2012

This study aimed at learning the characteristics of place identity of the Buan county hall garden and Sangsosan(上蘇山) by looking over the pattern and content of letter-engraved rocks and nearby facilities and history. Especially, we focused on the meaning and contents of the letters in Sangsosan and a Government Office of Buan engraved on rocks in order to learn what the place means. The results of our study are as follows. Buan-hyun(扶安縣) in the Joseon dynasty period blossomed literary culture of enjoying poetry and melody, and this was faithful realization of the concept of "Rakto(樂土)" of 'Saengubuan(生居扶安).' The grand scale letters written by Si-SooPark(朴蓍壽: 1767~1876), head of the office in the early 19th century, in the cursive style on the basis stone of the garden of Buan county building, which was the site of the office of Buan-hyun in the Joseon dynasty period, such as 'Bongraedongcheon(蓬萊洞天)', 'Jurim(珠林)', and 'Okcheon(玉泉)' mean that "'Bongrae', the another name of Buan', is a place where Taoist hermits would live because the spring water of Seorim flows down to be Okcheon.", showing his pride of living Buan. The regions like Seorimjeong, Geumdae(琴臺), and Hyecheon(惠泉) where letters engraved on rocks are located intensively are closely related with those who communicated with Mae-ChangLee(李梅窓: 1573~1610), the slave of the government, and are local attractions and garden traces where the literary culture and scholar's spirit of Buan are well-harmonized. Most of the letters were written from the 19th century to the early 20th century, showing that 4 for landscapes, 8 for Kyungseck(景色: imaginary scenry), 5 for figures, 15 for poems and 2 for others. The ratio of poems is much higher than that of poems in other regions' letters on rocks, and the keyword of the letters is Haecheon. A piece of the place identity heavily influenced by the Taois thermit ideology is revealed by the expressions of 'Bongraedongcheon', 'Sosansaho(蘇山四皓)' or 'the spring water of Haecheon' that was considered as an elixir of Taoist hermits. Seorim the forest, which had been managed after Yeon-Myeong Cho(趙然明: 1797~?), head of the office, planted trees in the 11th year of the reign of King Heonjong(1845), Seorimjeong in the forest, and rocks with engraved letters on them are proof of literary culture and the garden traces showing the characteristics and aspect of Imcheon(林泉) Garden of the office heavily influenced by the Taoist hermit ideology. Along with Naebyeon-san national park and Kyeokpo region, the center of Buan tourism, we hope that cultural heritages including rocks with engraved letters over Seorim park would become a representative cultural heritage and attraction of Buan.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.38 no.3
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• pp.11-24
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• 2020

The purpose of this study was to re-examine the neglected and forgotten Cheongdo Geoyeonjeong, to correct the wrong contents, examine the changes and conditions of the garden, and to establish basic data on the components of the forest in the future. In addition, it was extended to the Gongampungbyeog Cliff, the influence area of the Geoyeonjeongwonlim, and the results of the study were as follows; First, Based on the recitation of "Seonyu pungryu(仙遊風流)" in the "Cheongsuheon-yugo(聽水軒遺稿),", Dongchangcheon Stream and Gongampungbyeog(孔巖楓壁) were influenced by the outer gardens of the Georyeonjeongwonrim. Second, Small pavilion was built and arranged under the rock of Byeongam(Byeongpungbawi) in the management history of Geoyeonjeong Pavilion. The records show that Cheongsuheon used the Geoyeonjeong Pavilion as the original forest and even recognized Oewon, which is a scenic influence, as the Gongampungbyeog Cliff. Third, Many of the poems related to Gongam were recognized as Seunggyeong, which represents the Unmun area, and the eight scenery of Cheongdo and Unmungugok were established here as proof that Gongampungbyeog Cliff was very faithful to the traditional Seunggyeong aspect of Gongampungbyeog Cliff, and the crystalline structure of the location was implied as an external source of Geoyeonjeongwonlim. Fourth, The lower part of Dongchangcheon Stream, which stretches from Geoyeonjeongwonrim to Gongam, is filled with attractions consisting of cancerous areas such as Punghodae, Moseongam, Buangdae, Gokcheondae, Saganjeong, Hakgadae, and Hyeongjeam, which provide a clearer picture of the space and landscape of the Geyeonjeongwonrim Outer Garden. Fifth, The expression "dragging water, spilling it into the courtyard, and sending it back to the downtown of the field" of the Cheongsuheon-yugo suggests that the site of Geoyeonjeong Pavilion was originally a prevention. It is also inferred that Cheng Shu-heon also wanted to respect runners and pursue natural views like runners. Sixth, The record of planting a description of spring water and willow trees in "Geoyeonjeong Manyeong(居然亭晩影)」" and "Sanggukseol(霜菊說)」" suggests that the chrysanthemum was planted and planted, and that the chrysanthemum was used to describe the Osanggojeol(傲霜孤節), which means that he would not yield and keep his incision alone despite severe frost. Seventh, It is believed that the writing was written by Cheongsuheon in 1844 during the period of the creation of the Wonrim. The rock letters on the floor of Geoyeonjeong suggest the names of the receiving and the winning prizes. Most of the passages are based on nuclear power plants, including Muidogyo of the Zhuzi, and most of them incorporate the virtues of the Gunja and the natural views of the Eunja. In addition, the rock writing 'Gyeong(敬)' or 'Uidang(義堂)' is a substitute for special worship objects or introspection, adding to the significance and scenic properties of the Georyeon Garden Forest.

• Journal of the Daesoon Academy of Sciences
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• v.33
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• pp.91-145
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• 2019

This study aims to reveal that Daesoon Jinrihoe Yeoju Headquarters Temple Complex is a sacred place of Gaebyeokgongsa (the Reordering Works of the Great Opening) through the logic of the energy of form in Feng-Shui studies. The Headquarters Temple Complex can illuminate the lamp of coexistence, emerge as a place for cultivation, and support the era of human nobility with Gucheonsangje (the Supreme God of the Ninth Heaven) as an object of faith. Virtuous Concordance of Yin and Yang, Harmonious Union between Divine Beings and Human Beings, the Resolution of Grievances for Mutual Beneficence, and Perfected Unification with Dao are the mission statements of this great site. For this purpose, it is necessary to investigate the headquarters according to integral Feng-Shui Theory. Doing so can provide proof that the geographic location, landscape, yin-yang harmonizing, and flowing veins of terrestrial energy at Headquarters Temple Complex are all profoundly auspicious. At the same time, this data also allows further study into the interactions of dragon-veins, energy hubs, surrounding mountains, and watercourses, which reveal how Daesoon Jinrihoe Yeoju Headquarters Temple Complex promotes the basic works of propagation, edification, and cultivation and three societal works of charity aid, social welfare, and education for the purpose of global propagation, saving beings, and building an earthly paradise by reforming humanity and engaging in spiritual civilization. This must be done on site with proper Feng-Shui in order to open up the era of human nobility upon the Great Opening of the Later World. As the center of the religious order, Daesoon Jinrihoe, Yeoju Headquarter Temple Complex has the general Feng-Shui characteristic of Baesanimsu (a back supported by a mountain and a front facing water). Through discussing the Feng-Shui of Daesoon Jinrihoe's Yeoju Headquarters Temple Complex as the center of humankind's resolution of grievances for mutual beneficence, this study would explore growth-supporting land that delivers future rewards through Feng-Shui symbolism and the ethical practice of grateful reciprocation of favors for mutual beneficence. This exploration will reveal how the geographical features and conditions of the Yeoju Headquarters Temple Complex make it a place fit for spiritual cultivation. It is a miraculous luminous court surrounded by mountains, where auspicious signs in eight directions gather. Its veins of terrestrial energy harmonize with clean water energy as it is affectionately situated within its natural environment. Its location corresponds with the Feng-Shui theory of dragon-veins, energy hubs, surrounding mountains, and watercourses. Thus, with regards to the Feng-Shui of Daesoon Jinrihoe's Yeoju Headquarters Temple Complex, this study examines the flows of mountains and waters and focuses on how the site is based on the logic of Feng-Shui. More generally, the geographical features of the surrounding mountains are likewise examined. An analysis of the relationship between Poguk (布局) of Sasinsa (animal symbols of the four directions, four gods, including blue dragon of the east, red phoenix of the south, white tiger of the west, and black tortoise of the north) and the location will be provided while focusing on the Yeoju Headquarters Temple Complex. This study supports the feasibility of further Feng-Shui studies of the Yeoju Headquarters Temple Complex based on traditional geomancy books that focusing on Hyeonggi (Energy of Form) Theory.