• Progress in Superconductivity and Cryogenics
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• v.4 no.2
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• pp.27-30
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• 2002

One dimensional conduction equation is solved by finite difference method, to analyse the stability of Au/YBCO film deposited on a sapphire substrate. Joule heat is included in the case of current sharing state. The analysis shows the quench and recovery of superconductor depending on the amount of thermal disturbance release on the center surface of superconductor. The critical disturbance energies for different filling factor and operating current are calculated.

• Journal of the Chungcheong Mathematical Society
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• v.31 no.4
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• pp.397-409
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• 2018

In this paper, we investigate the generalized Hyers-Ulam stability of the functional equation $$f\({\sum\limits_{i=1}^{n}}x_i\)+{\sum\limits_{1{\leq}i<j{\leq}n}}f(x_i-x_j)-n{\sum\limits_{i=1}^{n}f(x_i)=0$$ for integer values of n such that $n{\geq}2$, where f is a mapping from a vector space V to a Banach space Y.

• Journal of Korean Dental Science
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• v.1 no.1
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• pp.22-27
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• 2008

Purpose : This study sought to evaluate the dimensional stability of the SITT (Silicone Index Tooth Tray) impression system and to determine whether providing space for wash impression material in SITT is a necessary step in obtaining accurate prostheses. Materials and methods : After mounting metal dies with shoulder and chamfer margins arbitrarily, SITT was fabricated using Blu-mousse$^{(R)}$. To test the dimensional stability of the SITT system for margin design, the shoulder margin and chamfer margin were evaluated. Furthermore, to test the effect of space for wash impression material, 0.5mm space in SITT and zero space in SITT were statistically compared. Results : 1. There was no significant difference between the group with shoulder margin and that with chamfer margin. 2. There was no significant difference between the group with 0.5mm space and that with zero space for wash impression material. Conclusions : Considering the limitations of this study, the dimensional stability of the SITT system did not interfere with the margin design. Space for the wash impression material was also unnecessary.

• KEPCO Journal on Electric Power and Energy
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• v.2 no.1
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• pp.127-131
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• 2016

Polymer electrolyte membrane for unitized regenerative fuel cells requires high proton conductivity, high dimensional stability, low permeability, and low cost. However, DuPont's Nafion which is a commercial polymer electrolyte membrane has high permeability, high cost, and decreasing proton conductivity and dimensional stability over $80^{\circ}C$. To address these problems, sulfonated poly ether ether ketone (sPEEK) which is a low cost hydrocarbon polymer is selected as matrix polymer for the preparation of polymer electrolyte membrane. In addition, composite membrane with improved proton conductivity and dimensional stability is prepared by introducing sulfonated graphene oxide (sGO). The fundamental properties of polymer electrolyte membranes are analyzed by investigating membrane's water content, dimensional stability, proton conductivity, and morphology. The cell test is conducted to consider the possibility of application of sPEEK/sGO composite membrane for an unitized regenerative fuel cell.

• Polymer(Korea)
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• v.34 no.6
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• pp.560-564
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• 2010

Dimensional stability of LCD polarization film consisted of triacetyl cellulose (TAC) and poly(vinyl alcohol) (PVA) film has been studied and especially, the effect of PVA adhesive on the dimensional stability has been considered as function of deacetylation and molecular weight of PVA adhesive. The maximum adhesion strength between TAC and PVA film was obtained in the laminate using PVA adhesive with 70% of OH content and the effect of molecular weight on the adhesion strength was only pronounced in the laminate using PVA adhesive with OH content above 70%. It was found that the optimum dimensional stability of TAC/PVA/TAC laminate (polarizing film) was obtained when applied PVA adhesive has low molecular weight and it was more dependent upon the OH content than the adhesion strength between TAC and PVA films.

• Journal of the Korean Wood Science and Technology
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• v.51 no.2
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• pp.133-144
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• 2023

Densification is an effective method for improving the physical and mechanical properties of low-density wood. However, the set-recovery of dimensions was found to be the problem of densified wood due to low fixation during the densification process. Alkali pretreatment before densification is thought to be a modification process to improve the dimensional stability of densified wood. In this research, the wood samples used were boiled in a 1.25 N sodium hydroxide (NaOH) solution at different times, followed by densification for 5 h at 100℃. The alkali pretreatment for 1, 3, and 5 h of boiling increased the dimensional stability of densified woods and anti-swelling efficiency values were 8.52%, 63.24%, and 48.94%, respectively. The boiling of wood in NaOH solution decreased the holocellulose content, as well as lignin to a lesser degree, and a lower crystallinity index was observed. The lower hydroxyl groups and a higher proportion of lignin in treated samples seem to have contributed to the high dimensional stability detected.

• Tunnel and Underground Space
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• v.9 no.2
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• pp.102-113
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• 1999

Two-dimensional and three-dimensional DEM programs, UDEC and 3DEC, were used to investigate the mechanical stability of the conceptual design of deposition drift and deposition holes constructed in a crystalline rock mass. From the simulations, the influence of discontinuities, the number of deposition holes, and deposition hole interval on the stability of deposition drift and deposition holes could be determined. From the two-dimensional and three-dimensional analysis. it was concluded that three-dimensional analysis should be carried 7ut fur deriving reliable conclusions. Even though the deposition hole interval changed from 8 m to 3 m, which did not damage the mechanical stability of the deposition drift.

• Journal of the Korean Society of Clothing and Textiles
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• v.23 no.1
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• pp.22-29
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• 1999

This paper descrived the changes of peel strength wrinkle recovery and dimensional stability after fusing 4 different wool face fabrics with 3 different fusible interlinings. The fusing condition was conducted by fusing press machine under 4kg.f/cm2 at 15$0^{\circ}C$. To determine the effect of the varous physical properties of the fused fabrics face fabrics and interlinings on the peel strength wrinkle recovery and dimensional stability(hygral expansion and relaxation shrinkage) of fused fabrics correlation among the KES values of fused fabrics face fabrics and interlinings to the peel strength rinkle recovery and dimensional stability of fused fabrics were expeerimentally analyzed,. As the results the peel strength was mainly influenced by the cover factor of face fabric and interlinings. After fusing wrinkle recovery and hygral expansion were decreased. The cover factor wrinkle recovery weight thickness shear rigidity and frictional properties of face fabric and the thickness of fused fabrics were not influence to the wrinkle recovery of fused fabrics. In addition the dimensional stabilities of fused fabrics were mainly influenced by the tensile and frictional properties of the wrinkle recovery of fused fabrics. In addition the dimensional stabilities of fused fabrics were mainly influenced by the tensile and frictional properties of the face fabrics.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.3080-3085
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• 2007

Shape optimization of the 3-dimensional WIG airfoil with 3.0-aspect ratio has been performed by using the multi-objective genetic algorithm. The WIG ship effectively floating above the surface by the ram effect and the virtual additional aspect ratio by a ground is one of next-generation and cost-effective transportations. Unlike the airplane flying out of the ground effect, a WIG ship has possibility to capsize because of unsatisfying the static stability. The WIG ship should satisfy aerodynamic properties as well as a static stability. They tend to strong contradict and it is difficult to satisfy aerodynamic properties and static stability simultaneously. It is inevitable that lift force has to scarify to obtain a static stability. Multi-objective optimization technique that the individual objectives are considered separately instead of weighting can overcome the conflict. Due to handling individual objectives, the optimum cannot be unique but a set of nondominated potential solutions: pareto optimum. There are three objectives; lift coefficient, lift-to-drag ratio and static stability. After a few evolutions, the non-dominated pareto individuals can be obtained. Pareto sets are all the set of possible and excellent solution across the design space. At any selections of the pareto set, these are no better solutions in all design space

• The Journal of Korean Academy of Prosthodontics
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• v.37 no.4
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• pp.506-515
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• 1999

Dental practice can produce and spread some infectious diseases from patients to dentist, dental assistant, and dental labors. One possible method for preventing these cross-contamination is to immerse dental impression in chemical disinfectants. So for many investigators studied on the dimensional changes of dental impressions and on the surface qualities of stone casts made from impression following immersion in disinfectants. This study was proposed to evaluate some popular impression disinfectant combination from the point of dimensional stability. Impression was taken from dental arch-shaped metal model. Irreversible hydrocolloid and 3 elastomers(polyvinyl siloxane, polysulfide, polyether) were immersed in 3 disinfectants (2% glutaraldehyde, 1% povidone-iodine, 0.5% sodium hypochlorite) for 10 minutes and measured both cross-arch and anterior-posterior distance under stereo microscope to evaluate dimensional change. The results obtained were as follows: 1. Dimensional changes of irreversible hydrocolloid impression was statistically different in cross-arch and anterior-posterior distance when immersed in 2% glutaraldehyde solution and in anterior-posterior distance when immersed in 0.5% sodium hypochlorite solution from control group (p<0.05). 2. Dimensional changes of polyvinyl siloxane and polysulfide impression were not statistically different from control group (p>0.05). 3. Dimensional changes of polyether impression was statistically different in cross-arch distance when immersed in 0.5% sodium hypochlorite solution and in anterior-posterior distance when immersed in 1% povidone-iodine solution from control group (p<0.05). 4. In all cases, dimensional changes were less than 0.1% from the original dimension and concluded clinically acceptable.