• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.31 no.4
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• pp.113-122
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• 2013

In this study, the traditional structure of the impact on the stability analysis. Korean traditional landscape architecture column space of stonework stable composition as the foundation of the fence for a long time been known to fall down and not maintained. The destination of research Ohgokmun Damyang Soswaewon fence which is in harmony with nature is one of the traditional structures that affect its shape without being kept so far came true. This includes our ancestral wisdom and that wisdom can guess guesswork. But I let the traditional reproduction incidence structures frequently. This deviation from the traditional method of construction application of shorthand stand. Thus, the subject of this study, the factors that do not fall down fences Ohgokmun solution is to indirectly gain the weak. In addition, epidemiological studies and the methods of calculation of the inferred physical examination, the results of the analysis were derived through the following. First, the internal factors of the fence Ohgokmun constituting the structural member and the coupling of the scheme. 1) based on stable ground. Greater role in the country rock The fact that the settlement will have no symptoms. 2) to minimize the friction caused by hydrological water to remove the two-pronged process through stone work building form and menu sustaining power in hydrology and flooding made against the bypass channel. 3) due to the load bearing capacity and durability to withstand the strength of the material and the construction of structures in the form of a dispersion of power between each individual to maximize the process of getting traction was applied. Second, external factors Ohgokmun fence the results obtained through the calculation of the dynamics of repair, is greatly affected by the wind and the water gate of the fence, but the action of the structural stability of the lack of power that hurt enough conclusion. In this study, the results of the structure of internal and external influence as well through the structure can be viewed as composed consisting. However, over the next follow-up in terms of climate and environmental factors due to the fact that the fall might.

• Korean Journal of Heritage: History & Science
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• v.51 no.1
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• pp.4-31
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• 2018

The Neolithic pottery excavated from the Jungsandong site has been classified into four types of pottery (I: feldspar type, II: mica type, III: talc type and IV: asbestos type) according to their mineral composition. These four types of potteries generally appear to have undergone incomplete firing, while the level of oxidation in the type I pottery objects, which have a relatively higher clay content, was found to be particularly low. The type III objects, which have a high talc content, are judged to have been somewhat slow in removing carbon because they contain saponite belonging to the smectite group. Of the four types of pottery, type IV showed the highest redness and the most uniform characteristics, thus indicating a good level of oxidation. In particular, fixed carbide (C; 33.7 wt.%) with a thickness of about 1mm, and originating from organic substances, was detected inside the walls of the type I pottery, while the deep radial cracks in the outer surfaces of the pottery are thought to have been caused by repeated thermal shocks. Given that all of the pottery except for the type I artifacts are considered to be have been made for storage purposes, those containing talc and tremolite are easy to done liquid storing vessels based on an analysis of their material characteristics. As for the type II relics, which are composed of various minerals and exhibit poor physical properties, they seem to have been used for simple storage purposes. As domestic talc and asbestos mines were concentrated in the areas of Gyeonggi, Gangwon, Chungbuk, and Chungnam, it seems likely that talc and tremolite were produced as contiguous minerals. Considering the distance between the remains in Jungsandong and these mines and their geographical distribution, there is a possibility - albeit somewhat slight - that these mines were developed for the mining of various minerals. Although ultramafic rock masses - such as serpentine capable of generating talc and tremolite - have not been found in the Jungsandong area, limestone and biotite granite containing mica schist have been identified in the northwestern part of Yeongjong Island, indicating that small rock masses might have formed there in the past. Therefore, it is judged necessary to accumulate data on pottery containing talc and tremolite, other than the remains in Jungsandong, and to investigate the rocks and soils in the surrounding area with greater precision. The firing temperatures of the pottery found at the Jungsandong site were interpreted by analyzing the stability ranges of the mineral composition of each type. As a result, they have been estimated to range from 550 to $800^{\circ}C$ for the type I artifacts, and from 550 to $700^{\circ}C$ for the type I, II and IV artifacts. However, these temperatures are not the only factors to have affected their physical properties and firing temperature, and the types, particle sizes, and firing time of the clay should all be taken into consideration.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.11a
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• pp.159-166
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• 2004

The beach, a margin between the sea and the land, is an extremely dynamic zone, for it is here that the motion of the sea interacts with the sediment, rock of the land or the artificial barriers. In order to prohibit or retard erosions due to the extreme Typhoon or storm induced waves, man has constructed these of temporary or more permanent nature, but they caused problems of other erosions from the secondary effect of them and a bad influence on the seascape. In considering the energy available to accelerate sediment transport and erosion in the surf zone, where the waves are broken, and offshore beyond the breaker line, the wave height and the wave period should be taken account. Hence, we tried to present an applicability of the submerged artificial Bio-reefs analyzing waves by a numerical model such that they could reduce the wave power without the secondary effect and restoration of marine ecologies. A new technique of beach preservation is by artificial reefs with artificial and/or natural kelps or sea plants. By engineering the geometry of the nearshore reef, the wave attenuation ability of the feature can be optimized Higher, wider and longer reefs provide the greatest barrier against wave energy but material volumes, navigation hazards, placement methods and other factors require engineering considerations for the overall design of the nearshore reefs.

• Geophysics and Geophysical Exploration
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• v.13 no.1
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• pp.69-79
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• 2010

In order to reduce leakage from a reservoir, a large amount of cement milk (grout) was injected from boreholes drilled around the shores of the reservoir, and monitored to establish the infiltration of cement milk into the bedrock under the reservoir. From laboratory tests using rock core samples, it was revealed that the resistivity of cement milk is much lower than that of the groundwater at this location. Therefore, it was expected that the resistivity of the zones filled with cement milk would be significantly reduced. Geophysical surveys are expected to be suitable methods to check the effectiveness of grouting in improving the water-retaining performance of a reservoir. DC electrical surveys (seven in total) and two Controlled Source Audio-frequency Magneto-Telluric (CSAMT) surveys were conducted along survey lines in the reservoir to monitor the infiltration of cement milk during the grouting. Extremely low resistivity zones ($10\;{\Omega}m$ or less) were observed in resistivity sections obtained by 2D inversion. The zones are inferred to be fractured zones filled with cement milk. In sections showing the rate of change of resistivity, three zones that showed significant change showed gradual expansion to deeper parts as the grouting progressed. These zones correspond to highly permeable zones detected by Lugeon tests at grout boreholes. We have confirmed that it is possible to measure the resistivity change by DC electrical and CSAMT surveys from the surface of the reservoir. It seems that such monitoring results could be reflected in future grouting plans.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.2
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• pp.926-933
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• 2012

Phosphoric acid used for the production of phosphate fertilizers is synthesized by the reaction of phosphate rock and sulfuric acid. As the reaction is exothermic, yield of phosphoric acid is poor at elevated temperature. Therefore, enhancement in its yield requires the process temperature be maintained by releasing the vapor ($80^{\circ}C$) containing HF and SiF4 through a vacuum cooler. However, these valuable resources; Fand Si, which can be utilized for the manufacture of refrigerant and polysilicon, respectively, are being wasted in the treatment process. We performed lab-scale experiments to estimate the amount of recoverable H2SiF6, a by-product of phosphoric acid manufacturing process. The experimental results showed a decrease of fluorine concentration by 0.12wt% in the liquid phase. Preliminary estimation showed a possible recovery of 5,509 ton/yr of fluorine considering the scale of the fertilizer manufacturing plant. Furthermore, field-scale experiment showed that H2SiF6 could be enriched in liquid phase from 0.35wt% to 7.33wt% and the vapor flow-rate from vacuum cooler was estimated at $51,000m^3/hr$. Anew, the efficiency of fluorine recovery in the pilot-scale experiment was found to be 76.74% and the production of H2SiF6 was estimated at 5,340 ton/yr.

• Journal of the Korean Geosynthetics Society
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• v.17 no.3
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• pp.19-32
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• 2018

Gravel Compaction Pile (GCP) method is currently being designed and constructed by empirical method because quantitative design method has not been developed, leading to various types of and frequent destruction such as expansion failure and shear failure and difficulties in establishing clear cause and developing measure to prevent destruction. In addition, despite the difference with domestic construction equipment and material characteristics, the methods applied to the overseas ground is applied to the domestic as it is, leading to remarkable difference between applied values and measured values in variables such as bearing capacity and the settlement amount. The purpose of this study was, therefore, to propose a reasonable and safe design method of GCP method by analyzing the settlement and stress behavior characteristics according to ground strength change under GCP method applied to domestic clay ground. For the purpose, settlement amount of composite ground, stress concentration ratio, and maximum horizontal displacement and expected location of GCP were analyzed using ABAQUS. The results of analysis showed that the settlement and Settlement reduction rate of composite ground decreased by more than 60% under replacement ratio of 30% or more, that the maximum horizontal displacement of GCP occurred at the depth 2.6 times pile diameter, and that the difference in horizontal displacement is slight under replacement ratio of 30%.

• The Journal of Korean Academy of Prosthodontics
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• v.41 no.5
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• pp.606-616
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• 2003

Purpose : The purpose of this study was to research the properties of some chemically cured methacrylate polymers such as MMA, HEMA, TEG-DMA, bis-GMA, GMA. Material and Method : 5 kinds of methacrylates were selected and added 2% tertiary amine and benzoyl peroxide to make a chemically curable polymer 25 micron crushed silicas which are treated with silane were selected as filler, they were added into methacrylate monomer until the consistency did not changed by the load of 500gram. All of the experimental resins were 5 kinds, and a serial test was done with 3 kinds of items including the filler contents, the tensile strength, and the bond strength. The number of specimen were 10 for each group. Filler contents were obtained by reducing the specimens to ashes at $600^{\circ}C$ for 1 hour. The specimens with the dimension of 6mm in diameter and 3mm thick were immersed in $37{\pm}1^{\circ}C$ distilled water for 24 hours before test, and tensile strength were measured with cross-head speed 1mm/min. Shear bond strength were mea sured on the specimens attached to bovine enamel etched with 37% phosphoric acid for 1 minute. Results : 1. Maximum filler incorporation was the highest as 75.5% on MMA, and the least as 53.4% on bis- GMA(p<0.0001). 2. The tensile stregth were MMA 141.3, GMA 154.3, TEG-DMA 157.4, bis-GMA 161.4 MPa, and HEMA showed the highest value, 226.9MPa(p = 0.0004). 3. The bond strength were GMA 10.1, TEG-DMA 11.7, HEMA 12.2, bis-GMA 13.3 MPa, and MMA showed the highest value, 15.3MPa, however statistical significances were not (p =0.3838), 4. TEG-DMA and HEMA were not different on the aspect of maximum filler contents and shear bond strength(p>0.05). Conclusion : HEMA can be used as an another diluent substituting TEG-DMA with the increased strength and with the constant bond strength and the constant filler contents.

• Journal of the Korean Geotechnical Society
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• v.35 no.11
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• pp.7-14
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• 2019

The compacted bentonite buffer is one of the major components of an engineered barrier system (EBS) for the disposal of high-level radioactive waste (HLW), and it is considered the best candidate for the buffer material. The buffer is located between disposal canisters and near-field rock mass, and it interrupts the release of radionuclide from disposal canisters and protect them from the penetration of groundwater. At initial disposal condition, degree of saturation of the compacted bentonite buffer decreases because of high thermal quantities released from the disposal canisters. However, the degree of saturation of the compacted bentonite buffer gradually increases caused by inflow of groundwater. The saturated and unsaturated behavior of the buffer is a very important input data since it can determine the safety performance of EBS. Therefore, this paper investigated water retention capacity (WRC) for the Korean compacted bentonite buffer. The WRC of the compacted bentonite buffer was derived by measuring volumetric water content and water suction when temperature variation was between 24℃~125℃ considering decrease of degree of saturation with respect to temperature increase. The WRC was also derived with the same volumetric water content under the room temperature condition, and it showed 1~15% larger water suction than high temperature condition.

• Journal of the Korean Society of Costume
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• v.40
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• pp.151-170
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• 1998

The purpose of this study is to examine the value of grotesque fashion and to predict the future fashion trend. The grotesque originates the formative art. It emerges towards of a century or transitional period in most case. In particular, it was used as the expressive method of an individual's inside and a satire on society through the work of artists in the Middle Age, the renaissance, the sym-bolism, the dadaism, the surrealism, the pop art, the technology art, and the post-modernism, etc. The grotesque in fashion is represented in the work of avant-garde fashion designers who lead the high fashion. The grotesque fashion which was combined with an image of non-formality, non-rationality, an absurdity and reality. It has been begun shape of female dress in the renaissance. Afterwards, it was represented in extremely exaggerated and distorted pop art, hippies' fashion in the 1960's. In the 1970's, it was reflected in genderless rock star and destructive punk fashion. It was also represented in the androgynous fashion which was combined with both sexes, the goth/gothic fashion which was expressed with a realistic and fanciful shape and the tattoo of skin-head in the 1980's. In the 1990's, the grungy look which was dirty and the cyber punk fashion. In general, it was also expressed by the avant-garde fashion designers. To sum up, a grotesque fashion which is expressed by experimental designers is classified into four shapes. 1, Union of some extraneous is expressed as different kinds of fashion theme, such as abnormality of texture, uses of surrealistic elements and chaos of sex. Although it appears that the abnormal union of grotesque has only discord and collision, it also shows a feeling of freedom for the tension. 2. Introduction of real and fanciful image is expressed as a cyborg, realistic description of disgusting animal skin and aggressive shape. Especially, it is worth while to notice Tierre Mugler and Alexander Macqueen's work which expressed the shape of mingling human of Middle Age. 3. distortion or exaggeration is expressed as an unformed shape, the exaggeration of a clothing size, the abnormal exaggeration of human body and the ignorance of clothing form. 4. Introduction of a disgusting image is expressed as an extremity of reality, motifs of death, clothing material of disgusting hair and the ostentation of sex. Motto which leads modern fashion is something new and shocking. The grotesque fashion is an expression of eagerness for something new. It often show something ironic in the form of humor which is embedded in an abnormal and shocking pattern. The grotesque fashion is represented as an extreme beauty. It will stand as an important element of the future fashion and as a particular style with the change and fluidity.

• Economic and Environmental Geology
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• v.38 no.2 s.171
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• pp.129-134
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• 2005

The $^{87}Sr/^{86}Sr$ ratios between water and biogenic material are similar in marine and lacustrine environment. Pb isotope ratios we, however, reported not to have been corresponding between the biological tissues and ambient water in aquatic system, contrary to the Sr isotope ratios. In order to explore the potential application of two isotopes as environmental tracers, we report here the isotopic compositions of strontium and lead of gastropod shell in fresh water in Jinan area. The $^{87}Sr/^{86}Sr$ ratios of carbonate shells of gastropod living in fresh stream water, are similar as that of ambient water but are different by sites. The different $^{87}Sr/^{86}Sr$ ratios of stream water between the sites is likely caused by the difference of the isotopic composition of Sr derived form rocks in the basin. In contrast, there is a distinct difference of the lead isotopic values between the water and the gastropod shell, suggesting that shell-fish available lead in aquatic system is different from dissolved lead in water. It is assumed that the majority of Pb in stream water is derived from atmospheric Pb accumulated on soil materials over years rather than from rock.