• Journal of Technologic Dentistry
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• v.30 no.2
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• pp.57-63
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• 2008

Statement of problem: Conventional techniques for implant framework fabrication produce significant error that is inconsistent with passive-fit requirement for osseointegrated implants. One of the etiologic factors which cause the errors is a sprue which may deform the framework during solidification and contraction. Purpose: This study was aimed to evaluate objectively effect of the sprue design on the accuracy of fit of implant prosthesis. Materials and method: Three different designs were considered relative to effect of casting accuracy. The first design had straight sprues and a button of excess alloy at the non-casting end of the sprues. The second was runner bar design(with the button). The last was straight sprues design(without the button). Gold cylinder and laboratory analogue had been used to diminish variables affecting to casting accuracy. Gold alloy and pressure-vacuum casting machine had been used. Marginal gap had been measured by SEM. One-way ANOVA and Duncan test had been used for statistical analysis. Results: The first design showed $79.87{\pm}13.95{\mu}m$ marginal gap. The second and third were $40.17{\pm}15.8{\mu}m$ and $35.17{\pm}9.95{\mu}m$ respectively. Conclusion: Straight sprues without button and runner bar designs were more accurate than straight sprues with button design(P<.05).

• Journal of the Korean School Mathematics Society
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• v.17 no.4
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• pp.805-816
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• 2014

In this paper, we survey the development of material implication and we present an analysis of the students' understanding of formal implication. Most of high school students consider material implication $p{\rightarrow}q$ as ${\sim}p{\vee}q$ when they represent the pattern of a collected cards as material implication $p{\rightarrow}q$. But when they collect cards in which material implication $p{\rightarrow}q$ is true, Most of high school students consider $p{\rightarrow}q$ as $p{\wedge}q$.

• Phonetics and Speech Sciences
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• v.4 no.1
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• pp.49-54
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• 2012

Recent studies on acoustic correlates of stress in English compounds and English phrases have revealed the difference of changes in acoustic manifestation between English compounds and English phrases with different intonation patterns. However, little effort has been made to compare Korean compounds and Korean phrases in different intonational environments. Therefore, this study focuses on the analysis of acoustic characteristics of Korean compounds and Korean phrases produced in different intonational sentence patterns (Subject, Question, Clause-Final, and Statement-Final). Measurements of vowel duration, intensity (dB) and pitch (in semitones) were compared. The results of the experiment in which 30 native speakers of Korean pronounced Korean compounds and Korean phrases (obtained from $8{\times}30$ sentences) in controlled prosodic and intonational environments reveal clear patterns that distinguish Korean compounds from Korean phrases and support the evidence of acoustic salience for phrases. Duration differences turned out to be a significant cue to distinguish Korean compounds and Korean phrases in all but the Clause Final position. According to the size effect, duration ratio is the most reliable cue to distinguish Korean compounds and Korean phrases followed by the pitch differences between the first syllable and the second syllable and the intensity ratio. Implications for Korean and English intonation training were also discussed.

• The Journal of Korean Academy of Prosthodontics
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• v.42 no.6
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• pp.641-646
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• 2004

Statement of Problem. Temporary soft relining materials are used in a diverse clinical situations such as tissue conditioner, relining material, functional impression by varying its viscoelasticity. However, reproduction of consistent viscoelasticity has been not possible. Materials and methods. Considering setting mechanism of this material, this study has measured the effect of varying amount of void in dynamic viscoelasticity of soft relining material, with three different mixing methods. In each methods 10 specimens were made and subjected to dynamic viscoelastic test which were measured at specific times over period of 72 hours. Results. The analysis of the result shown that there was no statistically significant differences between different mixing methods. Conclusion. Different mixing methods had no effect over control of viscoelasticity of soft lining material. Further research is recommended for under similar oral environmental condition.

• The Journal of Korean Academy of Prosthodontics
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• v.42 no.6
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• pp.679-684
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• 2004

Statement of problem. There have been few studies about the marginal fit of Auro Galvano Crowns. Purpose. The purpose of this study was to compare the marginal fit of the anterior single restorations. Material and methods. The in vitro marginal discrepancies of metal-ceramic, Auro Galvano Crown and coping were evaluated and compared. The Auro Gavano Crowns were made from one extracted maxillary central incisor prepared by milling machine. 30crowns per each system were fabricated. Measurements of a crown were recorded at 50 points that were randomly selected for marginal gap evaluation. Parametric statistical analysis was performed for the results. Results. Mean marginal gap dimensions and standard deviations at the marginal opening for the anterior single crowns were $74{\pm}21{\mu}m$ for the control (metal-ceramic restoration), $45{\pm}11{\mu}m$ for Auro Galvano Crown coping, and $51{\pm}9{\mu}m$ for the Auro Galvano Crown. Conclusions. Auro Calvano Crown showed significantly smaller (P<.05) marginal gap than the control. Ceramic application did not significantly affected the marginal fit of Auro Galvano Crown. (P>.05)

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.18 no.2
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• pp.193-207
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• 2014

In this paper we explore the emergence of the notion of compactness within its historical beginning through rigor versus intuition modes in the treatment of Dirichlet's principle. We emphasize on the intuition in Riemann's statement on the principle criticized by Weierstrass' requirement of rigor followed by Hilbert's restatement again criticized by Hadamard, which pushed the ascension of the notion of compactness in the analysis of PDEs. A brief overview of some techniques and problems involving compactness is presented illustrating the importance of this notion. Compactness is discussed here to raise educational issues regarding rigor vs intuition in mathematical studies. The concept of compactness advanced rapidly after Weierstrass's famous criticism of Riemann's use of the Dirichlet principle. The rigor of Weierstrass contributed to establishment of the concept of compactness, but such a focus on rigor blinded mathematicians to big pictures. Fortunately, Poincar$\acute{e}$ and Hilbert defended Riemann's use of the Dirichlet principle and found a balance between rigor and intuition. There is no theorem without rigor, but we should not be a slave of rigor. Rigor (highly detailed examination with toy models) and intuition (broader view with real models) are essentially complementary to each other.

• The Korean Journal of Rehabilitation Nursing
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• v.19 no.2
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• pp.128-137
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• 2016

Purpose: This study was designed to describe the experiences of dementia prevention program for older adults in nursing homes. Methods: Four focus group interviews (FGI) after the program were conducted with 35 participants. All interviews were audio-taped and transcribed verbatim. The transcribed data were analyzed by Colaizzi's phenomenological method. Results: Four themes emerged as a result of analysis. Participants without dementia reported "I don't have dementia yet." This statement probably reflects ignoring potential dementia. Motivation for participating the dementia prevention program were to reduce boredom, to enjoy exercising and communicating with others, and to follow group activities. Participants reported the positive effects of the program; (a) benefits from the repeating learned activities; (b) improvements of memory and emotional stability. A few participants reported their inability to follow the program due to physical and environmental limits. However, other participants reported their efforts to overcome physical limits and perform the activities regardless their limits. People who performed the activities with physical limits reported that their self-satisfaction was increased. Conclusion: Results of this study showed that participants without dementia were able to actively participate in dementia prevention programs and showed memory, emotional and behavioral improvements. Therefore, these findings can be used for developing customized dementia prevention programs in nursing homes.

• KIISE Transactions on Computing Practices
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• v.21 no.3
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• pp.167-172
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• 2015

Machine learning is a technique for training computers to be used in classification or forecasting. Among the various types, support vector machine (SVM) is a fast and reliable machine learning mechanism. In this paper, we evaluate the stock price predictability of SVM based on financial statements, through a fundamental analysis predicting the stock price from the corporate intrinsic values. Corporate financial statements were used as the input for SVM. Based on the results, the rise or drop of the stock was predicted. The SVM results were compared with the forecasts of experts, as well as other machine learning methods such as ANN, decision tree and AdaBoost. SVM showed good predictive power while requiring less execution time than the other machine learning schemes.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.2
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• pp.151-156
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• 2020

Small and medium enterprises (SMEs) play a very important role in developing countries. In Vietnam, SMEs operating in the field of handicrafts, besides contributing to the economy, also tasked to maintain and develop traditional handicrafts. However, accessing loans from banks of SMEs faces many difficulties. This study explores the determinants of bank lending decision for SMEs, particular, in traditional handicrafts business. Using dataset based on a survey conducted in Binh Duong province, Vietnam, we investigated to what determinant effects for loan approval. The analytical methods used include descriptive statistics for overall assessment, principal component analysis and regression to examine determinants of lending decisions. The results indicate that company's collateral was the most positive determinant to bank lending decision, follow by company's business plan. The role of company's leader is very important for banks considers to approve credit because company's leaders experience and relationship with stakeholders as well as banks have positive relations with bank's lending decision. Agreed with previous studies, the company's financial statement and company's credit history with banks are also significant determinants for lending decision. Whereas, the business environment seam unaffected lending decision as their relations is not significant..

• Structural Engineering and Mechanics
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• v.52 no.5
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• pp.1051-1067
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• 2014

The structures of concern in this study are subject to two types of forces: dead loads from the acceleration imposed on the structures as well as the installed operation machines and the additional adjustable forces. We wish to determine the critical values of the adjustable forces when buckling of the structures occurs. The mathematical statement of such a problem gives rise to a constrained eigenvalue problem (CEVP) in which the dominant eigenvalue is subject to an equality constraint. A numerical algorithm for solving the CEVP is proposed in which an iterative method is employed to identify an interval embracing the target eigenvalue. The algorithm is applied to four engineering application examples finding the critical loads of a fixed-free beam subject to its own body force, two plane structures and one wide-flange beam using shell elements when acceleration force is present. The accuracy is demonstrated using the first example whose classical solution exists. The significance of the equality constraint in the EVP is shown by comparing the solutions without the constraint on the eigenvalue. Effectiveness and accuracy of the numerical algorithm are presented.