• Journal of Technologic Dentistry
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• v.42 no.3
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• pp.213-219
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• 2020

Purpose: This study aimed to identify the impact of physical surface roughing with a polishing tool onto the pre-sintering yttria-stabilized tetragonal zirconia polycrystals (TZP) core and liner treatment for chemical bonding on the bond strength of TZP core and veneering ceramic. Methods: Overall, 80 specimens were classified into two groups (non-liner, NL; and usingliner, UL ) depending on the use of liner, and these two groups were then subclassified into four groups depending on the polishing tool used. (1) Non-liner groups: NS, non-liner+stone point; NC, non-liner+carbide bur; NP, non-liner+paper cone point; NT, non-liner+silicon point. (2) Using-liner groups: US, using-liner+stone point; UC, using-liner+carbide bur; UP, usingliner+paper cone point; UT, using-liner+silicon point. The pre-sintering surface roughing values and shapes were observed, and after burning up the veneering ceramic, the shear bond strength was measured using a universal testing machine. For significance testing, a one-way analysis of variance and Tukey's multiple comparison test were conducted. An optical microscope was used to observe the fracture plane, and the following results were obtained. Results: Surface roughness NP (4.09±0.51 ㎛) represented a higher value than other groups (p<0.001). In shear bond strength, NS (35.21±1.44 MPa) of the NL group showed the highest bond strength (p<0.001). The UL group did not show a statistically significant difference between groups (p=0.612). Conclusion: Our study findings reveal that the bond strength of TZP core and veneering ceramic was improved by pre-sintering physical surface treatment than by chemical bonding with liner surface treatment.

• Journal of Distribution Science
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• v.14 no.6
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• pp.99-106
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• 2016

Purpose - The antecedent to the relationship between the effect of the characteristics of strategic alliances and the performance of container liner shipping companies has been investigated in this study as container liner shipping companies' strategic alliances. It affects positively and negatively home, partner, and the third parties' performance in container liner shipping companies. Extensive literature reviews on shipper's strategic alliances reveal that strategic alliances in financial and non-financial performance of container liner shipping companies show the performance such as economic effects, business performance, global supply chain management performance, customer satisfaction, and forward integration and backward integration performance. The purpose of this study is to test empirically that the relationship between the characteristics of strategic alliances and financial and non-financial performance in container liner shipping companies. Structured equation modeling and confirmatory factor analysis were used to test the hypothesis using AMOS statistics program. Most previous researches focused on the relationship between the characteristics of strategic alliances and alliance types. There are few empirical studies that focus on business performance data because it is difficult to collect data in container liner shipping companies. However, this research measures financial and non-financial performance differently compared with the previous researches focusing on the characteristics of strategic alliances and alliance types measurements. Research design, data, and methodology - The conceptual model for the study is based on the studies of Lim (2010), Chen & Zhen (2009), and Wang & Meng (2014). The model is built around the factors of characteristics of strategic alliances and business performance. Cost, marketing, and service factors are regarded as proxy for the characteristics of strategic alliances. The financial and non-financial performance are regarded as proxy for the performance of strategic alliances. Based on the analysis of one hundred cases such as forwarder, shipper, and liner shipping companies, this study uses structural equation modeling to verify the effects of the characteristics of strategic alliances on business performance. Conclusions - This study provides container liner shipping companies to get some policy and practical implications in terms of the characteristics of strategic alliances and business performance. First, the cost factor for alliances characteristics has a positively significant influence on the financial and non-financial performance of strategic alliances. The cost factor relationship between high and low performance group does not have a significant difference on the performance of strategic alliances. Second, the marketing factor of alliances characteristics has a positively significant influence on the financial and non-financial performance of strategic alliances. The high performance group's marketing factor has a great non-financial performance than low performance group, but the low performance group's marketing factor has a grater financial performance than high performance group factor does. Third, the service factor of alliances characteristics has a negative influence on the non-financial performance of strategic alliances. The high performance group's service factor has a great non-financial performance than low performance group. Based on the findings from this study, related implications and future avenues deserve to be discussed.

• 한국기계연구소 소보
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• s.11
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• pp.5-12
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• 1984

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.6
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• pp.16-25
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• 2014

This study was investigated in optimum condition of pulping of ramie and the mechanical properties of non-woven fabric for the performance of ramie/cotton panty liner. The result of pulping condition on ramie was most suitable for type I (mixed NaOH with $Na_2CO_3$ in 30%:70%). The sample (I) was showed yield value of 68.2% and the best fibrillation and lignin removal rate. The non-woven fabrics of ramie/cotton were made in range of ramie content of 0, 15 and 30%. As ramie content increased, so were increased in air permeability, compressive strength and compression recovery rate. But surface roughness and compressional energy were decreased. Therefore, the non-woven fabrics of ramie/cotton are very suitable in hygienic goods for female panty liner. The ramie panty liner showed a little decrease in absorption and strength, as increasing the amount of ramie. But the performance of ramie panty liner was appeared beyond standard values used by usual panty liner.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.6A
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• pp.419-426
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• 2012

Fresh concrete has 10~20% extra water in it. As those water remain entrapped air in the concrete, life span of structures is reduced. For that reason, if extra water is eliminated, it will be useful to improve the durability of the structures. Though there were many reports about permeable formwork, the study on the properties of permeable liner itself has been insufficient. In addition, making holes on the form causes lowering of workability. Therefore, this study reviewed the properties of woven and non-woven permeable liner and formwork which has no holes on the form. For the woven and non-woven permeable liner, they showed great application with W/C decrease, lowering roughness, increased compressive strength of surface area and slight loss of cement paste, when the were applied to concrete. In addition, they showed different performance according to the density of woven liner or thickness of non-woven liner. Furthermore, when using the draining non-woven permeable liner which has drainage path inside, concrete surface showed required performance with high workability, without drilling the holes on the form.

• Journal of Technologic Dentistry
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• v.39 no.1
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• pp.43-52
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• 2017

Purpose: Physical and chemical properties of gold is most suitable to be restored of teeth to its original state. Recently zirconia was used instead of gold because of esthetical and intimacy of human body. Because of high strength and high abrasion resistance of zirconia, all zirconia artificial tooth lead to wear the original tooth of opposite site. To preserve this original tooth, zirconia artificial tooth covered with dental ceramic glass was used. When joining the zirconia core and dental ceramic glass, difference of their thermal expansion coefficient and wetting ability is generated the residual stress at interface lead to crack. In order to solve this problem, intermediate layer what is called zir-liner was imported to decrease the residual stress and increase the bonding strength. Methods: In this study, to identify the optimum conditions for manufacturing process, various methods to rough the surface of zirconia core were adopted, and vary the thickness of interlayer, and analyzed bond strength. Results: Bond strength of sanding specimens group showed higher than that of non-sanding specimens group, and once applied intermediate layer with sanding specimens showed highest bond strength with 28 MPa. SEM photomicrographs of zirconia cores fired at $1500^{\circ}C$ showed parallel straight lines in sanding and pockmarked surface in blasting surfaces as abrasion traces. Observation of the destruction section after shear test by SEM were carried out. Liner applied non-sanding group and non-liner applied sanding group all showed interfacial crack. Sandblasting group with non-liner showed remained dental ceramic glass on the surface of zirconia. Sandblasting group with once applied liner showed partially remained liner and dental ceramic glass on the surface of zirconia. XRD analysis revealed that sandblasting group showed higher monoclinic peaks than other specimens group and this result was due to the high collision energy for stress induced phase transformation. Conclusions: A study on the improvement of bonding strength between zirconia and dental ceramic glass steadily carried out for the future to practical use.

• Aerospace Engineering and Technology
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• v.2 no.2
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• pp.124-132
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• 2003

This paper described the structural design and the fabrication procedure of KSR-III composite pressure tank. The type of the composite pressure tank was COPV(Composite Overwrapped Pressure Vessel). A non-load sharing liner was made of aluminum 6061-0 and the liner provided a helium gas seal. The composite pressure tank was winded using T700 carbon/epoxy on the liner. Because the aluminum liner was thin, multiple cure cycles were applied to the filament winding technique. The multiple cure cycles prevented the liner-cylinder from losing a circular shape. A fitting force at the metallic boss was spread to the carbon fiber by a boss ring. The boss ring also prevented a local deformation at the boss part.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2005.11a
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• pp.45-48
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• 2005

In manufacturing process of composite cylinders with metal liner, the autofrettage process which induces compressive residual stress on liner to improve cycling life can be applied. In this study, finite element analysis technique is presented, which can predict accurately the compressive residual stress on liner induced by autofrettage and stress behavior after. Material and geometry non-linearity is considered in finite element analysis, and the Von-Mises stress of a liner is introduced as a key parameter that determines pressure cycling life of composite cylinders. Presented methodology is verified through fatigue test of liner material and pressure cycling test of composite cylinders.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.663-668
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• 2001

Strength evaluation was carried out for the cylinder liner of a low-speed marine engine. Calculation of temperature distribution, nonlinear structural analysis, material test, and fatigue strength evaluation are briefly introduced in this paper. Strengths of five liner models are compared, and the effect of materials experiencing different heat treatment is evaluated. Structural analysis including boundary and material non-linearities was performed for axisymmetric liner models. High cycle (fatigue limit) and low cycle (fatigue life) fatigue analyses are carried out. As results, localized high stress was occurred next to the mount line. Maximum stresses are varied significantly with respect to different liner models and different materials.

• Journal of Korea Port Economic Association
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• v.33 no.1
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• pp.89-110
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• 2017

The organization of the shipping conference -an international cartel, was approved by countries that recognized it for stabilizing routes as well as preventing excessive competition among liner shipping companies and recognized the characteristic of the liner service that is regularly repeated in the international liner shipping market. However, due to competition in bulk transportation and development of multimodal transport through new entrants, power expansion and vessel enlargement of non-aligned shipping companies; the shipping conference started collapsing, and was eventually abolished. As the shipping conference played an important role in the liner shipping market, there were changes in the competition structure of the liner shipping market, and this accordingly drove research on the effects of the abolition of the shipping conference on the liner shipping market. The effects of abolition of the shipping conference on the liner shipping market was analyzed after surveying the factors related to abolition of the shipping conference, and through the use of correlation and multiple regression analyses. Subsequent to the abolition of the shipping conference, the liner shipping companies increased global containership bottoms. Consequently, this led to fierce competition of freight charges. As a result, profitability of shipping companies diminished. However, shipping companies with a dominating cost structure recorded profits, while shipping companies with an inferior cost structure started recording a loss.