• Proceedings of the Korean Society For Composite Materials Conference
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• 2001.05a
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• pp.244-249
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• 2001

In this paper, we present the simultaneous measurement of the fabricaition strain and temperature during and after cure of unsymmetric composite laminate uising fiber optic sensors. Fiber Bragg grating/extrinsic Fabry-Perot interferometric (FBG/EFPl) hybrid sensors are used to measure those measurands. The characteristic matrix of sensor is analytically derived and measurements can be done without sensor calibration. A wavelength-swept fiber laser is utilized as a light source. FBG/EFPI sensors are embedded in a graphite/epoxy unsymmetric cross-ply composite laminate at different direction and different location. We perform the real time measurement of fabrication strains and temperatures at two points of the composite laminate during cure process in an autoclave. Also, the thermal strains and temperatures of the fabricated laminate are measured in thermal chamber. Through these experiments, we can provide a basis for the efficient smart processing of composite and know the thermal behavior of unsymmetric cross-ply composite laminate.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.38 no.1 s.113
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• pp.1-8
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• 2006

To overcome troubles in strength and process of linerboard caused by raw materials, a neutral sizing which is usual in fine paper making can be considered. A new sizing agent is necessary to show good performance in a system with high conductivity and COD. In this study, fast cure type AKD was examined as a new sizing agent and compared with conventional AKD. The effects of fixing agent addition and drying condition were also investigated. Fast cure type AKD which has a higher cationicity showed better sizing degree than conventional AKD in spite of low addition level and no curing treatment. And when fixing agent of sufficient amount was added, sizing degree was improved for both AKDs. High cationicity is a crucial factor for neutral sizing of linerboard for obtaining fast and stable sizing degree. Drying with temperature over $100^{\circ}$ was desirable for developing sizing degree.

• Design & Manufacturing
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• v.7 no.1
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• pp.60-63
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• 2013

Recently, Silicone that one of the thermo-sets is used to making optical products such as LED lenses because of excellent thermal properties. LED lenses are required to keep the precise dimensions, so they must be molded to have the minimum deformation. Thermo-sets have the expansion characteristic on the part of thermal property, it is important to optimize the cure condition so that the deformation of the part become minimum. In this study, to investigate the relationship between the shrinkage by the curing and expansion by the thermal properties of the resin, reactive injection experiment was performed by setting the variables such as mold setting temperature, cure time. As a result, it was confirmed that there was a interval while the thermal properties were transferred to more active during the cure process. It is expected to help in determining the reactive injection molding conditions of the thermo-set parts as well as LED lens in order to reduce the amount of deformation.

• Textile Coloration and Finishing
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• v.35 no.4
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• pp.246-255
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• 2023

In this study, we investigated for natural rubber foam to replace petrochemical-based neoprene foam. Experiments were conducted on vulcanization system and 2-step foaming process of natural rubber. The vulcanization system were EV(Efficient Vulcanization Cure), Semi-EV(Semi-Efficient Vulcanization Cure) and CV(Conventional Vulcanization Cure). In the 2-step foaming process, first molding temperature was 140℃, times were 15, 20, 25, and 30minutes, and the second molding temperature was 160℃, the times 5, 10, 15, and 20minutes. The cure and viscosity characterization were evaluated by oscillating disc rheometer (ODR) and mooney viscosmeter. Various mechanical characteristics, including hardness, tensile strength, elongation at the point of rupture, and tear strength, were quantified. Subsequently, an assessment of alterations in these mechanical attributes was conducted post-immersion in a NaCl solution. In addition degree of volume change was measured after immersing the NR foam in NaCl solution and the low-temperature permanent compression set was evaluated at 4℃. And expansion ratio and shrinkage ratio of NR foam were evaluated for 28 days. As a result the EV vulcanization system showed the least change in physical properties before and after salt water immersion, and the lowest shrinkage ratio for 28 days. In addition it was confirmed that the 2-step foaming optimum condition differed depending on the appropriate vulcanization condition.

• Journal of Acupuncture Research
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• v.17 no.3
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• pp.125-139
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• 2000

Study of the fourteen meridians that include name of P'ung(風) point. The results were summarized as follows. 1. Pyongp'ung(秉風) is located middle of the supraspinatous fossa(Small intestine Meridian, 手太陽小腸經). we can cute the local area disease and also use to cure the pathway of the Arm greater yang small intestine which is attacked by P'ung(風) disease. 2. Yep'ung(翳風) is located behind the lobule of the auricle, in the depression between the mastoid process and the mandible(Triple Energizer Meridian, 手少陽三焦經). we can cure the local area disease especially hyper yang disease and also use to cure the pathway of the Arm lesser yang triple energizer which is attacked by P'ung(風) and Yo'l(熱) disease. 3. P'ungmun(風門) is located 1.5 chon beside the lower end of the spine of the second thoracic vertebra(Bladder Meridian, 足太陽膀胱經). we can cure the local area disease and also use to cure the pathway of the Leg greater yang bladder which is attacked by P'ung(風) disease. 4. P'ungbu(風府) is located 1 chon above the middle of natural line of the hair at the back of the head, in the depression below the occiptal protuberance(Governor meridian, 督脈). It connects (Liver meridian, 足厥陰肝經) and Yin Link Vessel(陽維脈). we can cure the rigidity and pain in head and nape which is related Yin Link Vessel(陽維脈). 5. P'ungshi(風市) is located on the lateral part of the thigh, 7 hon above the patella(From the greater trochanter to the knee joint is 19 chon, Gallbladder Meridian (足少陽膽經). we can cure the local area disease(leg, knee, etc). 6. P'ungji(風池) is located Below the occipital bone, in the depression on the outer part of the trapezius muscle(Gallbladder Meridian, 足少陽膽經) on a level with P'ungbu(風府) (Governor vessel, 督脈). we can cure the local area disease and also use to cure the pathway of the Leg lesser yang gall bladder which is attacked by P'ung(風) disease.

• Textile Coloration and Finishing
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• v.14 no.3
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• pp.53-58
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• 2002

Cotton fabric was treated with TiO$_2$-PEG600 mixed solution by pad-dry-cure and wet-fixation process to improve the performance properties as well as antibiosis effect and its laundering durability. In this paper, the effects of concentration of $TiO_2/PEG$ and fixation process were investigated on laundering durability and properties of cotton fabric treated with glyoxal. As the concentration of $TiO_2/PEG$ increased fixation, W.I., K/S of treated cotton fabric increased. Application of wet-fixation method provided a further improvement in fixation, laundering durability of treated cotton fabric.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.13
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• pp.515-536
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• 2000

This study analyzes the U.S. case law which challenges the legal conclusions of the district court with respect to the applicability, and effect, of the doctrine of waiver and estoppel in addition to the doctrine of documentary cure. The impliations are as follows. First, the documentary cure requirement can not be interpreted to mean early enough to allow the beneficiary to cure and represent the documents before the presentment deadline or expiry date of letter of credit. The mere fact that the presentment period expired before the completion of bank's review and notification process does not compel any conclusion about whether the examiner spent a reasonable amount of time examining the documents. Indeed, the reasonable time requirement does not imply that banks examine a presentation out of order or hurry a decision based upon particular needs or desires of a beneficiary. Secondly, even if the doctrine of waiver can apply to letter of credit governed by the strict compliance standard, a one-time acceptance of discrepant documents by a bank does not waive the bank's right to insist upon conforming documents in all subsequent letter of credit transactions between the bank and beneficiary. Revised UCC Article 5 is highly persuasive on this point: waiver of discrepancies by issuer or an applicant in one or more presentation does not waive similar discrepancies in a future presentation. Neither the issuer nor the beneficiary can reasonably rely upon honor over past waivers as a basis for concluding that a future defective presentation will justify honor.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.7
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• pp.1661-1667
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• 2009

Post-cure characteristics of a silicone rubber material which is widely used for a LCD lamp holder were investigated using thermogravimetric analysis (TGA). Research was especially focussed on searching for the optimum post-cure conditions in relation to the practical operation environments. The results showed that incipient volatile temperature(Ti) during the process was considered as the most important factor and, thereby, post-curing for 2hrs at $250^{\circ}C$seemed to be a reasonable condition in the practical view-point. Arrhenius plot of shift factors which were empirically determined from the time-temperature-superposition-principle showed good linearity, exhibiting the post-cure mechanism might be proceeded through single mechanism with activation energy of 108.25kJ/mol.

• Composites Research
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• v.36 no.5
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• pp.315-320
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• 2023

In the manufacturing process of thermosetting carbon fiber composite materials using an autoclave, the internal temperature changes according to the set temperature cycle. This temperature change causes the resin in the composite material to cure. Heat is generated through the chemical reaction of the resin, which can result in a difference between the temperature inside the autoclave and the temperature of the composite material. Previous research assumed that the temperatures of the composite material and the autoclave were the same and analyzed to predict the residual stress and thermal deformation after manufacturing. However, these stresses and deformations depend on the temperature and degree of cure of the composite material. Therefore, this study verifies a thermal-chemical model analysis technique that takes into account the heat generated by the chemical reaction of the resin to accurately calculate the temperature and degree of cure. Additionally, case studies were conducted for different thicknesses to investigate whether this model exhibits similar trends across varying thicknesses.

• Restorative Dentistry and Endodontics
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• v.25 no.1
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• pp.123-132
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• 2000

To overcome problems of conventional glass ionomers, resin components have been added to glass ionomers. On a continuum between glass ionomers and composites are a variety of blends, employing different proportions of acid-base and free radical reactions to bring about cure. Popular groups defined between the ends are resin-modified glass-ionomers(RMGIs), polyacid-modified composite resins(Compomers) and ionomer modified resins. These groups show different clinical properties, and in selecting these materials for a restoration, one should sufficiently understand these different setting properties. In this study, some difference in the setting characteristics of different groups of hybrid ionomers were examined. Two RMGIs (Fuji2 LC,GC / Vitremer, 3M), three Compomers (Dyract AP, Dentsply / F2000, 3M / Elan, Kerr) were involved in this study. The identification of the setting characteristics of different groups was achieved by a two-stage study. First, thermal analysis was performed by a differential scanning calorimeter, and then the hardness of each group at different depth and time were measured by a micro-hardness tester. Thermal analysis was performed to identify the inorganic filler content and to record the heat change during setting process. The setting process was progressed for each material by chemical set mode and light-cured mode. In the hardness test, samples of materials were prepared with a 6mm-diameter metal ring, and the hardness was measured at the top, and 1mm, 2.5mm, 4mm below at just after a 40 second-cure, and after 10 minutes, 24 hours, and 7 days. Statistical analysis was performed by Mann-Whitney rank sum test to assess significant differences between set modes and types of materials, and by ANOVA and T-test to evaluate the statistical meanings of data at different times and depths of each materials. Followings are findings and conclusions derived from this study. Thermal analysis; 1. Compomers show no evidence of chemical setting while RMGIs exhibit heat output during the process of chemical setting. 2. Heat of cure of RMGIs exceed Compomers. 3. The net heat output of RMGIs through light-cured mode is higher than through chemically set mode. Hardness test; 1. Initial hardness of RMGIs immediately after light cure is relatively low, but the hardness increases as time goes by. On the contrary, Comomers do not show evident increase of the hardness following time. 2. Compomers show a marked decrease of setting degree as the depth of the material increases. In RMGIs, the setting degree at different depths does not significantly differ.