• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.10-11
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• 2019

Interior stone walls are using commonly in non-bearing lightweight walls of apartments. The stones of interior wall were two types, one is a granite stone, another is a marble stone. Granite stone is attached by the epoxy adhesive and marble stone is attached by dedicated anchor and fastener. The impact resistance test was carried out interior stone walls in accordance with KS F 2613. The test methods included the impact resistance tests by each of soft impact body and hard impact body. The results of the test have proved that interior stone walls can withstand the soft impact bodies and hard impact bodies that are likely to happen in everyday life.

• Structural Engineering and Mechanics
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• v.70 no.1
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• pp.67-80
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• 2019

Strengthening with near surface mounted carbon fibre reinforced polymers (NSM-CFRP) is a strengthening technique that have been used for several decades to increase the load carrying capacity of reinforced concrete members. In Iraq, many concrete buildings and bridges were subjected to a wide range of damage as a result of the last war and many other events. Accordingly, there is a progressive increase in the strengthening of concrete structures, bridges in particular, by using CFRP strengthening techniques. Near-surface mounted carbon fibre polymer has been recently proved as a powerful strengthening technique in which the CFRP strips are sufficiently protected against external environmental conditions especially the high-temperature rates in Iraq. However, this technique has not been examined yet under repeated loading conditions such as traffic loads on bridge girders. The main objective of this research was to investigate the effectiveness of NSM-CFRP strips in reinforced concrete beams under repeated loads. Different parameters such as the number of strips, groove size, and two types of bonding materials (epoxy resin and cement-based adhesive) were considered. Fifteen NSM-CFRP strengthened beams were tested under concentrated monotonic and repeated loadings. Three beams were non-strengthened as reference specimens while the remaining were strengthened with NSM-CFRP strips and divided into three groups. Each group comprises two beams tested under monotonic loads and used as control for those tested under repeated loads in the same group. The experimental results are discussed in terms of load-deflection behavior up to failure, ductility factor, cumulative energy absorption, number of cycles to failure, and the mode of failure. The test results proved that strengthening with NSM-CFRP strips increased both the flexural strength and stiffness of the tested beams. An increase in load carrying capacity was obtained in a range of (1.47 to 4.49) times that for the non-strengthened specimens. Also, the increase in total area of CFRPs showed a slight increase in flexural capacity of (1.02) times the value of the control strengthened one tested under repeated loading. Increasing the total area of CFRP strips resulted in a reduction in ductility factor reached to (0.71) while the cumulative energy absorption increased by (1.22) times the values of the strengthened reference specimens tested under repeated loading. Moreover, the replacement of epoxy resin with cement-based adhesive as a bonding material exhibited higher ductility than specimen with epoxy resin tested under monotonic and repeated loading.

• The korean journal of orthodontics
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• v.35 no.6 s.113
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• pp.443-450
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• 2005

This study was performed to compare the shear bond strength of orthodontic adhesive to amalgam according to different light sources (halogen-based light and light emitting diode (LED)) and amalgam surface treatments. Ninety extracted human premolars were randomly divided into 6 groups (4 experimental and 2 control groups) of 15 by light sources and surface treatments. Orthodontic brackets were bonded and shear bond strength was measured with an Instron universal testing machine. The findings were as follows: The bond strength of adhesive to amalgam surface was 3-5.5 MPa which was lower than that of acid-etched enamel (19 MPa) control. In the sandblasted amalgam surface, the shear bond strength of the halogen light group was higher than that of the LED group (p < 0.05) but. in the non-treated amalgam surface. there was no significant difference in the shear bond strength according to the light sources (p> 0.05). Within the same light source. sandblasting had no significant effect on the shear bond strength of the adhesive bonded to amalgam surface (p > 0.05). There was no significant difference in shear bond strength according to the light sources in acid-etched enamel control groups. This results suggest that there can be a limit in using light curing adhesives when brackets are bonded to an amalgam surface. Additional clinical studies are necessary before routine use of halogen light and LED light curing units can be recommended in bonding brackets to an amalgam surface.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.8
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• pp.489-493
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• 2016

In this study, the effect of vanadium oxide ($V_2O_5$) content and pre-sintering atmosphere on sealing property of glass frit that consisted of $V_2O_5-BaO-ZnO-P_2O_5-TeO_2-CuO-Fe_2O_3-SeO_2$ was investigated by XPS (X-ray photoelectron spectroscopy). The content of V2O5 was changed to 15, 30, and 45 mol%, and the pre-sintering was carried out in air and $N_2$ condition, respectively. XPS analysis conducted before and after laser irradiation with identical sample. Before laser treatment, glass frits that were pre-sintered at air condition showed both $V^{4+}$ and $V^{5+}$, but the valence state was changed to $V^{5+}$ after laser irradiation when the glass frits contained 30 and 45 mol% $V_2O_5$; this change led to non-adhesive property. On the other hand, glass frits that were pre-sintered at $N_2$ condition exhibited only $V^{4+}$ and it showed fine adhesion irrespective of the $V_2O_5$ content. As a result, the existence of $V^{4+}$ seems to be a major factor for controlling the adhesive property of glass frit for laser sealing.

• Journal of Korean Physical Therapy Science
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• v.3 no.2
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• pp.943-950
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• 1996

Taping is used to restrict undesired, potentially harmful motion and allow desired motion. Taping refers to the application of some type of adhesive backed tape, that adheres to the skin of a particular joint or to a limb. Prevention and rehabilitation is two main indications for the use of taping techniques. The purpose of this study was to compare a tennis injury between taping and non-taping group. The objects of this study were 64 tennis club members-38 non-taping group, 26 taping group. The analysis methods were both frequency and paired T-test. The results are followings: 1. There was effective increase of taping group-elbow, wrist, knee, ankle-that showed significant increase on statistical analysis. (P<.05). 2. There was effective a relation of seasons and injured in taping group-elbow, wrist, ankle-(P<.05) 3. But non-significant statistically about injured seasons. Prophylactic taping has become one of the most common methods employed to prevent sports injuries, despite questions regarding its efficacy. The success of taping does not only depend upon the materials or methods used, but also upon the phychologic sedative effect of the athlete to be taped.

• Journal of the Microelectronics and Packaging Society
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• v.10 no.3
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• pp.9-17
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• 2003

In this paper, thermo-mechanical and rheological properties of NCPs (Non-Conductive Pastes) depending on silica filler contents and diluent contents were investigated. And then, thermal cycling (T/C) reliability of flip chip assembly using selected NCPs was verified. As the silica filler content increased, thermo-mechanical properties of NCPs were changed. The higher the silica filler content was added, glass transition temperature ($T_g$) and storage modulus at room temperature became higher. While, coefficient of thermal expansion (CTE) decreased. On the other hand, rheological properties of NCPs were significantly affected by diluent content. As the diluent content increased, viscosity of NCP decreased and thixotropic index increased. However, the addition of diluent deteriorated thermo-mechanical properties such as modulus, CTE, and $T_g$. Based on these results, three candidates of NCPs with various silica filler and diluent contents were selected as adhesives for reliability test of flip chip assemblies. T/C reliability test was performed by measuring changes of NCP bump connection resistance. Results showed that flip chip assembly using NCP with lower CTE and higher modulus exhibited better T/C reliability behavior because of reduced shear strain in NCP adhesive layer.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.22 no.4
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• pp.330-340
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• 2019

Human breast milk contains numerous biomolecules. Human milk oligosaccharides (HMOs) are the third most abundant component of breast milk, after lactose and lipids. Amongst the synthetized HMOs, 2'-fucosyllactose (2'-FL) and lacto-N-neotetraose (LNnT) are widely studied and are considered safe for infant nutrition. Several studies have reported the health benefits of HMOs, which include modulation of the intestinal microbiota, anti-adhesive effect against pathogens, modulation of the intestinal epithelial cell response, and development of the immune system. The amount and diversity of HMOs are determined by the genetic background of the mothers (HMO secretors or non-secretors). The non-secretor mothers secrete lower HMOs than secretor mothers. The breastfed infants of secretor mothers gain more health benefit than those of non-secretor mothers. In conclusion, supplementation of infant formula with 2'-FL and LNnT is a promising innovation for infant nutrition.

• Journal of Technologic Dentistry
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• v.35 no.1
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• pp.43-48
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• 2013

Purpose: This study aimed to investigate the shear bond strength for non-precious alloy castings without beryllium, which has been used repeatedly for economical reason. Methods: The Schmitz-Schulmeyer test method was used to evaluate the shear bond strength between the non-beryllium Ni-Cr alloy Vera Bond 2V(AlbaDent, Inc. USA) and the Ceramco 3(Dentstply, York, PA, USA) porcelain powder. The maximum loading and shear bond strength were measured. The average shear strength(MPa) was analyzed with the one-way ANOVA and the Tukey's test( =.05). The fracture specimens were examined using Microscope to determine the failure pattern. Results: The mean shear bond strengths(SD) in MPa were group A(100% new metal) control 28.72(3.31); group B(50% new + 50% reused) 27.28(1.13); group C(all reused) 26.61(5.47). Microscope examination showed that group A and B specimens presented mixed failure, and group C specimens showed adhesive failure. Conclusion: In conclusion, forward this non-precious alloy dose not contain beryllium for how should use a more systematic study and for future advanced research is performed giving effect to be considered desirable.

• Korean Chemical Engineering Research
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• v.45 no.5
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• pp.493-499
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• 2007

Polymeric hydrogel particles were fabricated to demonstrate the scale-up possibilities with the Particle Replication In Non-wetting Templates (PRINT) process. A permanently etched, specifically designed master was made on a silicon wafer using conventional photolithography, then reactive ion etching. The master and substrate were used repeatedly to make a large number of identical elastomeric perfluoropolyethers (PFPE) replica molds. The PFPE replica molds were used to fabricate and harvest individual, monodisperse micron-sized particles using the PRINT process. A water-soluble polymer adhesive was used as a sacrificial layer for harvesting particles. Particles were composed of biodegradable poly (ethylene glycol) diacrylate (PEG-diA), and aminoethylacrylate (AEM) and 2-acryloxyethyltrimethyl ammonium chloride (AETMAC) were added to them for improving the uptake of the cells. This study suggested PRINT used to produce the uniformed and shape specific biodegradable polymer is the effective technique for the non viral vector for the drug and the gene delivery.

• The korean journal of orthodontics
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• v.29 no.5 s.76
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• pp.599-611
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• 1999

The purpose of this study was to evaluate shear, tensile and shear/tensile combined bond strengths(SBS, TBS, S/TBS) in various orthodontic brackets bonded to human teeth with chemically cured adhesive (Ortho-one, Bisco, USA). Five types of metal brackets with various bracket base configurations (Micro-Loc base(Tomy, Japan), Chessboard base(Daesung, Korea), Non-Etched Foil Mesh base(Dentarum, Germany), Micro-Etched Foil Mesh base(Ortho Organiners, USA), Integral base(Unitek, USA)) were used in this study. Shear, tensile and shear/tensile combined bond strengths according to the direction of force were measured by universal testing machine. The bracket base surface after bond strength test were examined by stereoscope and scanning electron microscope. The assessment of resin remnant on bracket base surface was carried out by ARI(adhesive remnant index). The results obtained were summarized as follows, 1. In all brackets, SBS was in the greatest value(p<0.05), TBS was in 50% level and S/TBS was in 30% level of SBS. 2. In bond strength, Micro-Loc base bracket showed the maximum bond strength($SBS:22.86{\pm}1.37kgf,\;TBS:11.37{\pm}0.42kgf,\;S/TBS:6.69{\pm}0.34kgf$) and Integral base bracket showed the minimum bond strength($SBS:10.52{\pm}1.27kgf,\;TBS:4.27{\pm}1.08kgf,\;S/TBS:2.94{\pm}0.58kgf) (p<0.05). 3. In bond strength per unit area, Integral base bracket showed the minimum value, Micro-Loc base and Chessboard base brackets were in similar value(p>0.05). Non-Etched Foil Mesh base and Micro-Etched Foil Mesh base bracket were similar in SBS and TBS(p>0.05), but Micro-Etched Foil Mesh base bracket was greater than Non-Etched Foil Mesh base bracket in S/TBS(p<0.05). 4. Bond failure sites were mainly between bracket base and adhesive, therefore ARI scores were low.