• Earthquakes and Structures
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• v.8 no.3
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• pp.761-778
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• 2015

The objective of this paper is to report the result of an experimental program conducted on the strengthening of nonductile RC frames by using external mesh reinforcement and plaster application. The main objective was to test an alternative strengthening technique for reinforced concrete buildings, which could be applied with minimum disturbance to the occupants. Generic specimen is two floors and one bay RC frame in 1/2 scales. The basic aim of tested strengthening techniques is to upgrade strength, ductility and stiffness of the member and/or the structural system. Six specimens, two of which were reference specimens and the remaining four of which had deficient steel detailing and poor concrete quality were strengthened and tested in an experimental program under cyclic loading. The parameters of the experimental study are mesh reinforcement ratio and plaster thickness of the infilled wall. The effects of the mesh reinforced plaster application for strengthening on behavior, strength, stiffness, failure mode and ductility of the specimens were investigated. Premature and unexpected failure mode has been observed at first and second specimens failed due to inadequate plaster thickness. Also third strengthened specimen failed due to inadequate lap splice of the external mesh reinforcement. The last modified specimen behaved satisfactorily with higher ultimate load carrying capacity. Externally reinforced infill wall composites improve seismic behavior by increasing lateral strength, lateral stiffness, and energy dissipation capacity of reinforced concrete buildings, and limit both structural and nonstructural damages caused by earthquakes.

• Journal of Technologic Dentistry
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• v.13 no.1
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• pp.15-19
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• 1991

This study was made to effect on the porosity when model making for control of vibrator. Samples of total 600 were made by plaster and stone divided low, medium and high which is 100 each. The following results were obtained to observation porosity of surface by eyes. 1. Second stage was fewer than third stage, first stage was fewer than third stage in porosity number of plaster model. 2. Second stage was fewer than first stage in porosity number of stone model. 3. Stone model was fewer than plaster model in porosity number of third stage.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.133-134
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• 2017

The In the experiment on flow using sand walls, when white clay+sand was mixed with glutinous rice, traditional paper and seaweed as adherents and preventive measures for cracks, the flow was higher than other sand wall mortars. This indicates that it is effective in improving flow. Moreover, in terms of strength, a mix of white clay+sand, traditional paper and flour had a greater strength than a mix of white clay+sand, straws and flour. In the experiment to test for cracks and shrinking during drying, a composition of white clay+sand+traditional paper showed fewer cracks and less shrinking than the walls where straws were mixed in.

• Journal of the Korean Ceramic Society
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• v.30 no.12
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• pp.1029-1038
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• 1993

The microstructures of aluminas, included of dissolved CaO as $\alpha$-alumina seeded pseudo-boehmite hydrosol was gelled in plaster mold and doped of MgO as dipping of calcines(120$0^{\circ}C$-2h) into Mg-nitrate solution, were compared to the one of which additives are excluded during the gellation. It was formed the boundary layer of 300~350${\mu}{\textrm}{m}$ distance from surface to the inside, containing of approximately 500ppm CaO by dissolved Ca from plaster mold. As the MgO addition to the boundary layer with dissolved CaO, the microstructure of the layer was uniformed and inhibited the grian growth, compared to one of that additives be excluded specimen and of MgO doped-inside region. This result was considered as abnormal grain growth and effect of flat boundary formation be appeared by effects of dissolved CaO, were decreased by MgO co-doping.

• Journal of the Korean Ceramic Society
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• v.28 no.12
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• pp.1019-1025
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• 1991

The effect of dissolved Ca ion from plaster mold during slip casting on the microstructure and fracture toughness of high-purity sintered alumina were investigated. When the alumina slip containing 1000 ppm MgO was casted on a calcined alumina mold, the sintered compact had a homogeneous microstructure with equiaxed grains. However, when the same slip was casted on a plaster mold, the sintered compact consisted of the mixture of equiaxed and elongated grains. This inhomogeneous microstructure was also observed in the sintered alumina doped with 100o ppm MgO and 100 ppm CaO whose compact was prepared on the calcined alumina mold indicating that the inhomogeneity was caused by CaO. It was found that the specimen containing both MgO and CaO had higher fracture toughness than that containing MgO only. The enhanced fracture toughness by CaO is probably due to the crack deflection along the boundaries of the elongated grains.

• KIEAE Journal
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• v.11 no.2
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• pp.91-96
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• 2011

The purpose of this study is to measure the environmental effects of different alternative building materials. The following building materials were tested: clay bricks, cement wall, and red-clay plaster. Four mock-up models were constructed using clay bricks, cement wall, red-clay plaster and the last model as the control model. The effects of the above four building materials on temperature, humidity, the emissions of formaldehyde, and V.O.C were measured. This experiment was conducted during September. The conclusions are as follows. Clay bricks were able to control temperature, humidity and filter formaldehyde by itself. The environment within the cement wall was not affected by the humidity changes outside. Red-clay plaster walls had little impact on the environment because it is very thin.!

• Structural Engineering and Mechanics
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• v.56 no.2
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• pp.189-200
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• 2015

The topic of this study is to investigate behaviors of masonry walls strengthened with reinforced fiber plaster under diagonal tensile loads. Full blend brick $100{\times}50{\times}30mm$ in dimensions were used to make masonry walls with dimensions of $400{\times}400{\times}100mm$. Three different samples were manufactured by plastering masonry walls with traditional style, with 3% polypropylene or with 5% steel fiber. All the samples were tested using ASTM 1391-81 standards. The propagation of damage on samples caused by diagonal tensile load was observed and load-displacement graphs were plotted for each sample. A finite element software (ABAQUS) was used to obtain numerical values for all samples and crack patterns and load-displacement responses were obtained. Experimental and numerical results were compared.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.11 no.1
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• pp.197-218
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• 1998

In this study, I invastigate about oriental medical drug, dosage form and directions in external therapy of contact dermatitis. and after study on relationship oriental medical drug, dosage form and directions with cause, symptom and differentiation of symptom and sign. The results are as follows; 1. Most frequently used oriental medical drug is until qing(淸) dynasty Eriocheir sinensis H. Milne-Edwards(蟹), Salix babylonica L.(柳葉), Natrii sulfas(芒硝), Allium macrostemon Bge.(해), Nelumbo nucifera Gaertn.(荷葉), nowadays in Korea and China Phellodendron amurense Rupr.(黃柏), Gypsum(石膏), Rheum palmatum L.(大黃), Baphicacanthus cusia Bremek(靑黛), Talcum(滑石). 2. In the frequency of dosage form, until qing(淸) dynasty powder 1case, liquor 49cases, liquer and solid mixture 58cases, nowadays Korea and China powder 16cases, liquor 96cases, liquer and solid mixture 59cases. 3. Most frequently used directions of dosage is thinly attaching method(薄貼法), attaching method(敷貼法), furnigating and cleansing method(熏洗法), cleansing method(洗傷法), wet dressing method(濕敷法), spreading powder method(撲粉法), plaster method(途차法), rubbing skin method(摩擦法) 4. In the external therapy of contact dermatitis, oriental medical drug's usage is based on stage of contact dermatitis In acute stage, most frequently used drug is heat and damp remove drug(淸熱燥濕藥), nature of drug(藥性) is bitter taste and cold charactor(苦寒), In chronic stage, most frequently used drug is nourishing the blood drug(養血藥), promoting blood circulation drug(活血藥). 5. The dosage form of drug is based on symptom. In acute stage, when papules and vesicles, or erosion and exudation is the main symptom of skin, liquor or powder is used, when erosion and crust is the main symptom of skin, plaster is used. In chronic stage, plaster is used. 6. In the directions of dosage is based on dosage form of drug and symptom. In acute stage, when papules and vesicles is the main symptom of skin, fumigating and cleansing method, cleansing method, plaster method is used, when erosion, vesicles and exudation the main symptom of skill, cleansing method, wet dressing method, spreading powder method, attaching method, spreading powder method is used, when crust is the main symptom of skin, plaster method is used. In chronic stage, plaster method, rubbing skin method is used.

• YAKHAK HOEJI
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• v.42 no.1
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• pp.25-30
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• 1998

This study was designed to compare the absorption fraction and extent of ketoprofen gels and a matrix typed ketoprofen plaster patch. 3g (90mg as ketoprofen) of the two gels whi ch has oleohydrogel or hydrogel as a base, respectively, and 3 pieces of plaster patches (90mg as ketoprofen) were, applied in the area of 210$cm^2$ on forearm in 12 volunteers by cross over design. Blood samples were collected serially up to 24 hours and the plasma concentrations of ketoprofen were analyzed by HPLC using flurbiprofen as an internal standard. The detection limit of the assay was 1ng/ml of ketoprofen in plasma. The pharmacokinetic parameters (e.g. $AUC_{24hr}$, $AUMC_{24hr}$, MRT, Fraction Absorbed) were calculated from the plasma concentrations time data of each volunteer. The oleo-hydrogel showed significantly higher absorption fraction and extent of ketoprofen than the current hydrogel. The mean plasma concentrations of the oleo-hydrogel were increased to 98.46${\pm}$23.15ng/ml by 6 hour after application, and increased futher to 100.61${\pm}$18.65ng/ml at 24 hour. On the other hand, those of the hydrogel were increased 17.61${\pm}$18.65ng/ml at 5 hour to 34.68${\pm}$9.65ng/ml at 24 hour gradually. Therefore the plasma concentrations of oleo-hydrogel at each measured time were 3~7 times greater than those of the hydrogel with statistical significance. The $AUC_{24hr}$ (1797.26${\pm}$52.09ng.h/ml) of the oleo-hydrogel was 3.5 times greater (P<0.05) than that (516.17${\pm}$104.52ng.h/ml) of the hydrogel. The plaster patches showed higher bioavailability ($AUC_{24hr}$ 2877.37${\pm}$578.27ng.h/ml) than the olea-hydrogel ($AUC_{24hr}$ 1797.26${\pm}$52.09ng.h/ml) without statistical significance. But the absorption fraction of the oleo-hydrogel was rather higher than that of the plaster patches during the first 6 hours after administration. These results suggest that newly developed ketoprofen gel which is used oleo-hydrogel as a base would show excellent skin permeation on topical application for the corresponding clinical indications and could be absorbed as well as plaster patches.

• The Journal of the Korean dental association
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• v.36 no.4 s.347
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• pp.289-295
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• 1998

Toothash and Plaster of Paris(Calcium sulfate) mixture have been studied for development of new biomaterial since 1992. I have performed the experimental and clinical study for evaluation of biocompatibility and possibility of bony defect reconstruction and clinical application. These materials are biocompatible, osteoconductive and resorbable. Main component of toothash is hydroxylapatite. In the future, I will perform the systematic construction of material and additional research.