• 보존과학연구
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• s.29
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• pp.5-18
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• 2008

Hanji among paper, which is material for support of the organic artifact such as painting and Thangkas, is given as much importance as the original material in the conservation treatment of artifacts. This lining paper can go through physical and chemical deterioration due to its organic nature, and inflict serious damage to the original materials of the artifact. There is a lot of difficulty in keeping continuous production of the paper mulberry fiber based on lining paper due to a short supply of raw material and discontinuation of traditional method. Also restoration and conservation treatment is done by relying only on the knowledge and skill of few experts without any recognized manual based on scientific analysis. In this study, we evaluated the stability of lining paper which is used to support organic artifact. As the result of experiments, this lining paper was made from mulberry tree in Korea and produced by means of oebal method, but was not treated by starch in its surface.

• Journal of the Korean Wood Science and Technology
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• v.45 no.6
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• pp.828-835
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• 2017

Airtightness of buildings is one of critical aspects of its energy performance. To build up references of airtightness of wooden houses built in Korea, blower door tests have been carried out in 42 houses since 2006. Causes of air leakage were investigated recently. The average value of air change rate was $3.7h^{-1}$ for light frame house and $5.5h^{-1}$ for post-beam construction at ACH50 (air change per hour at 50 Pa air pressure difference). Foam type insulation was more advantageous in ensuring building airtightness than glass fiber batt. Airtightness of wooden houses which were constructed after 2010 was improved to have less than $1.5h^{-1}$ of ACH50, threshold for application of artificial air change. The average air change rate of CLT (cross laminated timber) houses showed the lowest value, $1.1h^{-1}$, among the tested structures.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.1
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• pp.122-127
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• 2010

This study involved the making of sugar snap cookies with the addition of carrot powder at two to twelve percent which furnishes modern people with much lacking and needed dietary fiber. The review of the physiochemical properties, rheology and sensory evaluation of such contents resulted in the following findings: The sedimentation value and Pelshenke value all decreased in weak flour with the addition of more carrot powder, in comparison with the control group. The water retention capacity (WRC) and alkaline water retention capacity (AWRC) all increased in weak flour with the addition of more carrot powder in comparison with the control group. As for the gelatinization properties of the test samples measured by rapid visco-analysis, the addition of more carrot powder resulted in the initial pasting temperatures increasing in the case of weak flour, yet showing no significant difference between the control group and the carrot-added groups, as well as the maximum viscosity, minimum viscosity and final viscosity all showed the tendency of decreasing. The addition of more carrot powder led to the peak times in the mixographs for weak flour all exhibiting the tendency of decreasing, which might be interpreted as gradually weaker physical properties of the dough as well as less stability in the shape of the dough in turn.

• Journal of the Korean Society of Tobacco Science
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• v.36 no.1
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• pp.1-11
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• 2014

Cigarette filters containing Brassica Rapa L. seeds of the dark brown and round shaped were evaluated to determine the effect of seed addition on filter degradability. The seeds with germination capability under the tar/nicotine condition in the preliminary test, were put into the active carbon part of the filter(12mm) during filter rod making by the kit. The $4{\pm}2$ pieces of the seeds were put into the opened fiber bundle of the filter tow. In order to test the germination rate of the seeds, seed filters were placed either in a petri dish or test-pot in a conditioned area ($25^{\circ}C$, 70 % RH). The seed filters were placed outdoors exposed to natural conditions with the periodic water supply. The seeds in the smoked filters showed 90 % germination rate after a month under the open air condition. No significant differences in the sensory evaluation and analysis were obtained when the control sample was compared to the same cigarettes with the seeds.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.1195-1205
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• 2008

Composite piles have been used in ground conditions where conventional piles are unsuitable or uneconomical. They may consist of a combination of timber and concrete pile in Europe. One method of doing this was to drive a steel tube to just below water level, and a concrete pile was lowered down it and driven to the required level where corrosion was susceptible in U.K. Recently, a fiber reinforced polymer (FRP) composite pile was developed to use in many marine locations for piers and waterfront buildings in the USA(Hoy, 1995; Phair, 1997). A steel composite (SC) pile reinforced concrete spun pile with steel tube was also proposed and used for the foundation acting a high lateral earthquake load. Composite piles have been developed and researched to increase lateral resistance or to prevent corrosion in marine structures. In paper, the composite pile consisting of the steel upper portion and the concrete lower portion is proposed and are carried out several tests to confirm the capacity of the pile such as lateral load test, dynamic load tests and bending test. It is noted that the composite pile would be a economical pile being capable of increasing lateral resistance.

• The Journal of the Korea institute of electronic communication sciences
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• v.7 no.3
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• pp.567-571
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• 2012

To design the long-haul optical communication system, we need to decide the type of optical fiber and optical amplifier, span length of optical amplifier, dispersion compensation method, optical signal power, etc. Therefore, we need to predict the performance of optical communication system when we change one of the system parameters. In this paper, we investigate the method of predicting the maximum transmission length of the designed optical communication system and finding the optimum optical signal power to obtain the maximum transmission length.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.549-552
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• 2006

Generally the ultra-high strength steel reinforced concrete has rich mix composition composed of high-strength type mineral admixtures and as a result of very low water-binder ratio(about under w/b=25%), it reveals ultra-high compressive strength(about over 100Mpa). Also, in order to obtain sufficient toughness after construction, we usually mix a large quantity steel fiber with ultra-high strength steel reinforced concrete therefore we must use proper mixer for workability. When we make the ultra-high strength steel reinforced concrete we need more long mixing time or much super-plasticizer than when we manufacture normal concrete. These bring about economical problems and performance deterioration. Therefore, in this study, in order to manufacture easily ultra-high strength steel reinforced concrete we develope a dedicated mixer for ultra-high strength steel reinforced concrete with high speed type. It carried out the examination for comparison between the dedicated and general type mixer, the analysis and counterplan of the point at issue when we manufacture ultra-high strength steel reinforced concrete by the dedicated mixer.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.201-204
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• 2008

The proposed method, capable of predicting various stress-strain responses in axially loaded concrete confined with FRP (Fiber Reinforced Polymers) composites in a rational manner, is based on the fact that the volumetric expansion due to progressive microcracking in mechanically loaded concrete is an important measure of the extent of damage in the material microstructure. The elastic modulus expressed as a function of area strain and concrete porosity, the energy-balance equation relating the dilating concrete to the confining device interactively, the varying confining pressure, and an incremental calculation algorithm are included in the solution procedure. This procedure enables the evaluation of lateral strains consecutively according to the related mechanical model and the energy-balance equation, rather than using an empirically derived equation for Poisson's ratio or dilation rate as in other analytical methods.

• Fibers and Polymers
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• v.5 no.3
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• pp.245-251
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• 2004

Poly(trimethylene terephthalate-co-trimethylene 2,6-naphthalate)s (P(TT-co-TN)s) with various copolymer composition were synthesized, and their chain structure, thermal property and crystalline structure were investigated by using $^1$H-NMR spectroscopy, differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD), respectively. It was found from sequence analysis that all the P(TT-co-TN) copolymers synthesized have a statistical random distribution of TT and TN units. It was also observed from DSC thermograms that the glass transition temperature increases linearly with increasing the TN comonomer content, whereas the melting temperature of copolymer decreases with increasing the corresponding comonomer content in respective PTT- and PTN-based copolymer, showing pseudo-eutectic melting behavior. All the samples melt-crystallized isothermally except for P(TT-co-66 mol % TN) exhibit multiple melting endotherms and clear X-ray diffraction patterns. The multiple melting behavior originates from the dual lamellar population and/or the melting-recrystallization-remelting. The X-ray diffraction patterns are largely divided into two classes depending on the copolymer composition, i.e., PTT and PTN $\beta$-form diffraction patterns, without exhibiting cocrystallization.

• Fibers and Polymers
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• v.1 no.1
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• pp.6-11
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• 2000

In the polycondensation reaction of polyethyleneterephthalate(PET), $Sb_2$$O_3$, can react effectively as a catalyst, if physically transformed. $Sb_2$$O_3$ powder is transformed into liquid solution by dissolving in ethylene glycol(EG). Homogeneous catalyst is made by mixing this liquid solution with glycols having different solubility. The efficient reaction of PET polymerization is expected by using homogeneous catalyst. PET was synthesized using homogeneous catalysts of 4 wt.% $Sb_2$$O_3$ solution dissolved in glycol[EG, 2,2-bis(4-(2-hydroxyethoxy)phenol)propane(BHPP), neopentyl glycol(NPO), and 1,3-propandiol(PD)]. PET using EG-BHPP($Sb_2$$O_3$) catalysts shows the highest I.V. within a reaction time of 120 min. In the p-d analysis, PET using EG-BHPP($Sb_2$$O_3$) catalysts has the fastest propagation rate and slowest degradation rate. EG-BHPP($Sb_2$$O_3$) catalysts are more efficient than EG($Sb_2$$O_3$) catalysts and $Sb_2$$O_3$ powder catalysts.