• Restorative Dentistry and Endodontics
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• v.7 no.1
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• pp.101-106
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• 1981

The purpose of this study was to estimate the ability of the marginal fit of Glass ionomer cement. Using the human extracted teeth and 2% acqueous solution of methylene blue, the author investigated the marginal penetration of dye in restorative materials such as Amalgam, Hi-Pol, Glass ionomer cement, Estic microfill and Restodent. The results were as follows. 1. All filling materials showed some degree of marginal penetration. 2. Glass ionomer cement revealed nearly the same microleakage as Estic microfill and Hi-Pol, but showed inferior effect of the marginal seal as compared with Restodent. 3. It is appeared that Amalgam has more effective ability of the marginal fit than the others within a week.

• Restorative Dentistry and Endodontics
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• v.16 no.2
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• pp.143-154
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• 1991

The purpose of this study was to evaluate the sealing ability of five obturation methods in conjunction with sealer. Fifty extracted upper and lower anterior teeth were selected and the access cavities were prepared lingually with a round bur. The working length was determined with a #15K file, and the root canals were instrumented with a #40K file 1mm short of the apical foramen. The apical third of root canal was flared by step-back technique and the coronal two thirds of root canal using #2 - 3 Gates Glidden drills. And then, the teeth were randomly assigned to five groups of 10 teeth each. A thin coat of Tubliseal was placed into the canal into the canal using the # 35 reamer and the canals were filled by lateral condensation, vertical condensation, ultrasonic activated lateral condensation, ULTRAFIL injecting, and McSpadden compaction methods. All teeth were stored in 100 % relative humidity at 31c for 48 hours. The roots were suspended in 2 % methylene blue solution for 48 hours, left to dry for 24 hours and then, half side of root was removed longitudinally using the fissure bur. A Boley gauge wes used to measure the distance, to the nearest 0.1mm, from the apical foramen to the most coronal level of dye penetration. The measurement of dye penetration was statistically compared by Duncan's multiple range test The results were as follows 1. Ultrasonic group showed the best sealing ability among the all experimental groups, but there were statistically no significant difference in the sealing ability between ultrasonic group and vertical condensation group. 2. There were no statistically significant difference in the sealing ability among the lateral, vertical, and ultrasonic groups. 3. McSpadden group showed the worst sealing ability among the all exprimental groups.

• Geomechanics and Engineering
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• v.12 no.5
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• pp.771-783
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• 2017

Using a transparent fracture replica with aperture size and water-cement ratio (w/c), the factors affecting the penetration behavior of rock grouting were investigated through laboratory experiments. In addition, the waterproof efficiency was estimated by the reduction of water outflow through the fractures after the grout curing process. Penetration behavior shows that grout penetration patterns present similarly radial forms in all experimental cases; however, velocity of grout penetration showed clear differences according to the aperture sizes and water-cement ratio. It can be seen that the waterproof efficiency increased as the aperture size and w/c decreased. During grout injection or curing processes, air bubbles formed and bleeding occurred, both of which affected the waterproof ability of the grouting. These two phenomena can significantly prevent the successful performance of rock grouting in field-scale underground spaces, especially at deep depth conditions. Our research can provide a foundation for improving and optimizing the innovative techniques of rock grouting.

• Journal of Wellbeing Management and Applied Psychology
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• v.4 no.4
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• pp.15-25
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• 2021

Purpose: The purpose of this study is to form a new cosmetic market through the development of a composition with high skin permeability after adding omega 3 to Aloe Vera soothing gel products. Research design, data and methodology: In this study, omega-3 fatty acids were added to cosmetic products in the form of soothing gels. By applying nanoparticle technology to rapidly increase the penetration of raw materials into the skin, characteristics related to skin moisture and regeneration were determined. Omega-3 was used as a raw cosmetic material. Then 5% and 15% nanoparticle aqueous products containing omega-3 were prepared. The developed water hydrate was subjected to skin permeability test using artificial skin. Results: 53 hours of artificial transdermal penetration of the developed composition, the ethanol-based omega-3 containing nanoparticle solubilized raw material was about three times higher penetration than the ethanol-based omega-3 containing nanoparticle solubilized raw material. Conclusions: The raw material product (SR-1901) containing 5% of omega-3 nanoparticle water hydrate has skin regeneration ability and pain reduction effect. It can be expected that the skin cosmetics market will be reorganized into a new distribution structure and opportunity through omega-3 supplemented soothing gel cosmetics with improved efficacy than existing cosmetics.

• Restorative Dentistry and Endodontics
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• v.13 no.1
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• pp.103-111
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• 1988

The purpose of this study was to, examine the sealing ability of the denting bonding agent, when used with gutta percha cone, as a root canal sealer. Seventy two upper and lower extracted human teeth with single root were randomly selected and instrumented in a conventional method with K-file. After instrumentation and dry the canal with paper point, there were divided into three groups and twenty four teeth in each group were filled with the following material; In group I: Scotchbond in combination with gutta percha cone. In group II: AH 26 in combination with gutta percha cone. In group III: Tubli-Seal in combination with gutta percha cone. All specimens were immersed in Indian Ink, decalcified, and cleared. The depth of dye penetration into the canals were evaluated by caliper at the intervals of 1 day, 1 week, 2 weeks. The results were as follows; 1. Depth of dye penetration for all groups increased with time. 2. As to difference in mean dye penetration at time interval of 1 day and 14 days, Scotchbond group exhibited the smallest value as 0.53mm and Tubli-Seal group exhibited the largest value as 0.70mm. 3. There was the difference of dye penetration between each group, but its difference was not significant, statistically.

• Clinical and Experimental Reproductive Medicine
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• v.18 no.1
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• pp.73-80
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• 1991

We compared fertilizing potential measurements by the zona-free hamster egg penetration assay with the in vitro fertilization and embryo transfer program was evaevulated for their ability to fertilize zona free hamster egg. Spermatozoa from 12 presumeably fertile donors and from the male partners of 56 infertile couples were evaluated for their ability to fertilizing potentials. Penertration rates of fertile donors were $36.2{\pm}27.7%$ ; Fertilization rates of infertile couples between with normal semen parameters and with abnormal semen parameters were $28.7{\pm}19.1$, $5.7{\pm}8.9%$, respectively. Sperm motility of couples with penetration rates between on 15-30% and on 30> were $54.1{\pm}4.6$, $55.5{\pm}8.3%$ respectively. Hamster penetration rates of couples participating in an in vitro fertilization and embryo transfer program was $38.9{\pm}29.9%$. But in one case, a positive fertility assessment was obtained in the absence of fertilization of the wife's eggs attributable to egg immaturity. This method may have potential value as a diagnostic tool in evaluation human sperm fertilization capacity which avoids the ethical and logistical problems associated with fertilizing of human eggs in vitro.

• Journal of the Korean Geotechnical Society
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• v.30 no.10
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• pp.33-44
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• 2014

The preliminary design of suction pile as the supporting system for concrete floating structures was performed for the pilot project of the southwest coast area in Korea. Prior to starting design work, site conditions of the area including ground and hydraulic conditions, and a 100-year return period external force were throughly evaluated. The suction pile for mooring of the offshore floating structures has to satisfy the lateral resistance against external force as well as the penetration ability according to the soil conditions such as soil types, shear strengths, effective stresses, and seepage forces. In the design, the required penetration depths, which were stable for lateral resistance, were evaluated with the diameters of cylindrical suction pile as the final installing ones. And the design suction pressures at each penetrating depths, at which sand boiling did not occur, were assessed through the comparison of penetration and penetrationresistance forces. As a result, it was impossible for suction piles with the diameter range of 3.0~5.0 m to penetrate into required penetration depths. On the other hand, suction piles with the diameter range of 6.0 m and 7.0 m satisfied both the horizontal stability and the penetration ability by design suction pressures at the required penetration depths of 8.5 m and 8.0 m, respectively.

• Laser Solutions
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• v.1 no.1
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• pp.30-38
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• 1998

This study includes the efface of shielding gas types on $CO_2$ laser weldability of low carbon automotive galvanized steel. The types of shielding gas evaluated are He, $CO_2$, Ar, $N_2$, 50%Ar＋50%$N_2$. The weld penetration, strength, formability(Erichsen test) of Laser weld are found to be strongly dependent upon the types of shielding gas used. Further, the maximum travel speed and flow rate to form a keyhole weld is also dependent upon types of shielding gas. The ability of shielding gas in removing plasma plume and thus increasing weld penetration is believed to be closely related with ionization/dissociation potential, which determine the period of plasma formation and disappearance. Further, thermal conductivity and reactivity of gas with molten pool also give strong effect on penetration and porosity formation which in turn affect on the formability and strength.

• Restorative Dentistry and Endodontics
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• v.15 no.1
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• pp.81-87
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• 1990

The purpose of this study was to evaluate the apical seal produced by low temperature($70^{\circ}C$) injection gutta percha technique(ULTRAFIL) with & without sealer, warm latero-vertical cindensation technique (ENDOTEC) with & without sealer, and the lateral condensation technique with sealer. 100 extracted, single rooted human teeth were divided into 5 groups and root canals were enlarged & obturated according to the purpose of this study. Obturated teeth were immersed in 2.5% methylene blue for 48hrs. at $37^{\circ}C$ incubator and split. The apical sealing ability was evaluated by measuring the degree of dye penetration into the canal. The results were as follows: 1. All group showed varying depth of dye penetration. 2. There were no significant difference among Group I (lateral condensation), Group II (ULTRAFIL with sealer) & Group IV (ENDOTEC with sealer) (P>0.05). 3. There were less dye penetration when used in conjunction with sealer (P<0.001).

• Journal of Welding and Joining
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• v.29 no.6
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• pp.71-76
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• 2011

Submerged arc welding method from both sides is generally applied to the welding of main panel manufacturing process during ship construction. The tandem SAW method is applied to improve the productivity. The various weld defects that occur during tandem SAW method are melt through, incomplete penetration, undercut and overlap etc. It could be thought that the reasons for these defects are mainly lack of prediction ability for penetration depth and deposited metal area. In this research, total 5 kinds of welding factors for experiment like current of lead pole, voltage of lead pole, current of trail pole, voltage of trail pole and welding speed are adopted. Weld tests are carried out for the analysis of variation effects of these factors on penetration depth and deposited metal area. Based on the test and analysis results, it is possible to obtain the prediction equation for the effect of these factors on the amount of deposited metal and penetration depth. As per the verification of the results by additional tests, it is confirmed that the prediction equation, include a error margin of ${\pm}2mm$ for penetration depth and ${\pm}10mm2$ for deposited metal area.