• The Journal of Korean Academy of Prosthodontics
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• v.42 no.5
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• pp.514-523
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• 2004

Statement of problem: All-ceramic restorations have been advocated for superior esthetics. Various post and core systems have been used to improve the strength of damaged teeth, but it is unclear whether they affect the final shade of finished all-ceramic restorations. Purpose: The influence of different types of post and core systems on light transmission through all-ceramic crowns was assessed by spectrophotometric analysis. Also the masking effect of different thickness of ceramic ingot was evaluated. Material and Methods : Forty-five sample disks (15mm in diameter) at several thickness(1.0, 1.5, 2.0mm) and value(shade 100, 200, 300) were made in heat pressed ceramic(IPS-Empress). Background specimens simulating gold-alloy cast posts(Type III casting gold alloy), metal posts(Ni-Cr casting alloy) and ceramic posts(CosmoPost) were fabrica-ted. Resin composite(Z250, A3 shade) was used as a tooth substrate reference. For each combination, the change in color was measured with a spectrophotometer. Readings were performed for 2 conditions (1) ability of ceramic to mask the core in relation to its thickness(1.0, 1.5, or 2.0mm) ; (2) influence of post and core types on the final color of the ceramic. Data were recorded according to the CIE $L^*a^*b^*$ systems and color difference($\Delta$E) was calculated. Results: 100 shade ingot: when ceramic thickness was 1.0mm, $\Delta$E value for ceramic post larger than 1 but $\Delta$E value for metal and gold post was larger than 2. For ceramic thickness of 1.5mm, only $\Delta$E value for metal was larger than 2, and the other samples' $\Delta$E value was smaller than 2. For ceramic thickness of 2.0mm, $\Delta$E values for all specimens was smaller than 2. 200 shade ingot: when ceramic thickness was 1.0mm, $\Delta$E value for ceramic post was smaller than 1 but $\Delta$E value for metal and gold post was larger than 2. For ceramic thickness of 1.5 mm, only the $\Delta$E value for metal was larger than 2, and the other samples' $\Delta$E value was smaller than 2. For ceramic thickness of 2.0mm, $\Delta$E values for all specimens was smaller than 1. 300 shade ingot: when ceramic thickness was 1.0mm, only $\Delta$E value for metal was larger than 2 and the other samples' $\Delta$E value was smaller than 2. For ceramic thickness of 1.5mm, $\Delta$E values for all specimens was smaller than 1. For ceramic thickness of 2.0mm, $\Delta$E values for all specimens was smaller than 1. Conclusion: The final esthetic result of the IPS-Empress glass-ceramic restoration was not affected by the presence of different core materials when the thickness was more than 2.0 mm. When ceramic thickness decreases to 1.5mm, it is advised to take the substrate aspects into consideration. If the ceramic thickness is less than 1.0mm, using the tooth color matched substrate is strongly recommended.

• Journal of Korea Foundry Society
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• v.5 no.3
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• pp.5-12
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• 1985

Many researchers have studied the eutectic solidification of CV Graphite Cast Iron qualitatively. However quantative studies have not been done. The type of eutectic solidification of CV Graphite Cast Iron treated with CG Alloy (Fe-Si-Mg-5Ti-Ca-Ce) was studied quantitatively through M.D.E. value (Mushy Degree of Eutectic Solidification) = $t_2/t_1)$, where $t_1$ is the difference of the eutectic solidification starting time between surface and center part of the casting sample, and $t_2$ is the time of eutectic solidification of the center part. Following results were obtained. (1) The M.D.E. value of CV graphite cast iron lies between that of spheroidal graphite and that of flake graphite cast iron but is closer to that of Flake graphite cast iron. (2) The M.D.E. value of CV graphite cast iron depends upon CV ratio. (3) The time required for eutectic solidification increases as graphite form is changed from Flake, CV. to spheroidal graphite. (4) The M.D.E. value increases as cooling rate increases.

• Proceedings of the Korean Information Science Society Conference
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• 2006.10a
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• pp.17-21
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• 2006

도메인 기반 단백질 상호작용 예측 기법은 지난 몇 년 동안 활발히 연구되어 왔다. 도메인 기반 접근 방법 중에서도 도메인 조합 기반 단백질 상호작용 가능성 순위 부여 기법은 예측 정확도면에서 다른 기법보다 월등한 결과를 보여주고 있다. 그러나 학습 집단을 사용하는 특징 때문에 전체 도메인 정보를 이용할 수 없는 단점이 있다. 또한, 이 시스템은 도메인 정보가 부족하여 다른 기능을 하는 단백질이라도 같은 도메인 정보를 보여주기 때문에 예측 시스템의 결점을 드러내고 있다. 도메인 조합 기반 단백질 상호작용 가능성 순위 부여 기법은 InterPro 데이터베이스의 도메인 정보를 기반으로 사용한다. InterProScan은 InterPro의 여러 멤버 데이터베이스의 정보를 기반으로 Sequence 분석을 하는 소프트웨어로써 검색 후 단계에서 찾아낸 결과들을 e-value를 기반으로 여과한다. 본 논문에서는 제시된 e-value를 조정 방법을 사용함으로써 단백질 내 도메인 패턴의 다양화와 기존 도메인 정보가 없던 단백질의 도메인을 새롭게 발견할 수 있으나 접근 방식의 한계가 존재함을 확인할 수 있었다.

• Journal of Korea Society of Digital Industry and Information Management
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• v.13 no.1
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• pp.159-171
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• 2017

The purpose of this study is to investigate the effects of e - commerce technology characteristics and personal values on purchasing behavior by information security importance. The results of the empirical study that examined the university students in 2006 and 2016 are as follows. First, personal value is centered on personal values, such as self - esteem and self - esteem in 2006. In 2016, however, personal values such as self - fulfillment and personal relationship with others are important. Transactional ease and product service serve as the main value of the fun and pleasure of life, but the sense of accomplishment as the core value of information protection. Second, the technical characteristics of e-commerce are as follows. In terms of ease of transaction and product service, technology characteristics are simplified and directly effected over time. On the other hand, information protection works very closely with individual value, There was a strong tendency to enjoy benefits. Especially in 2006, if you want to enjoy transactional convenience through transaction information security or benefit from product service, it has been changed to recognize the importance of information security through payment in 2016.

• Journal of the Korean Society of Clothing and Textiles
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• v.9 no.2
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• pp.13-26
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• 1985

In this study, when cotton fabrics dyed with Direct dyes are treated under various resin concentration 2, 4, 8, 12, $14\%$ with ureaformaldehyde(UF) and melamineformaldehyde(MF) resin which can be imparted the crease recovery to textiles, chang of properties on lightfastness, washfastness, crease recovery, breaking strength, etc. and color changes are investigated. the results are as follows 1) Color difference(${\Delta}$E) increased but K/S value decreased according to the increase of resin cone. such tendency showed that MF treated fabrics and soaping fabrics were evident than UF treated fabrics and non-soaping fabrics. 2) In lightfastness, ${\Delta}$E and K/S value of resin treated fabrics were reduced as compared with untreated fabrics according to the increase of resin cone. The lower ${\Delta}$E and K/S value of MF than ${\Delta}$E and K/S value of UF showed low lightfastness of MF. pH of resin treted fabrics was almost unaffected with lightfastness. 3) In washfastness, ${\Delta}$E and K/S value of resin treated fabrics decreased slightly as com-pared with untreated fabricsaccording tothe increase of resin cone. The ${\Delta}$E and K/S value of MF decreased lower than UF. But in the case of the higher resin cone. than about $8\%$, they were not almost differentiated. 4) As resin cone. increased, crease recovery considerably increased but breaking strength and elongation decreased. The fabrics treated with UF were good crease recovery, whereas the fabrics treated with MF were good breaking strength. 5) Soaping appeared to improve the lightfastness, washfastness, crease recovery but appeared to work adverse effect on breaking strength.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.165-170
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• 2023

Isolation of the culture broth of a marine-derived Acremonium sp. CNQ-049 guided by HPLC-UV yielded compound 1 (3-phenethyl-2-phenylquinazolin-4(3H)-one), and its inhibitory activities against monoamine oxidases (MAOs), cholinesterases (ChEs), and β-secretase 1 (BACE1) were evaluated. Compound 1 was an effective selective MAO-B inhibitor with an IC₅₀ value of 9.39 µM and a selectivity index (SI) value of 4.26 versus MAO-A. In addition, compound 1 showed a potent selective butyrylcholinesterase (BChE) inhibition with an IC₅₀ value of 7.99 µM and an SI value of 5.01 versus acetylcholinesterase (AChE). However, compound 1 showed weak inhibitions against MAO-A, AChE, and BACE1. The Ki value of compound 1 for MAO-B was 5.22±1.73 µM with competitive inhibition, and the Ki value of compound 1 for BChE was 3.00±1.81 µM with mixed-type inhibition. Inhibitions of MAO-B and BChE by compound 1 were recovered by dialysis experiments. These results suggest that compound 1 is a dual-functional reversible inhibitor of MAO-B and BChE, that can be used as a treatment agent for neurological disorders.

• Journal of the Korean Data and Information Science Society
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• v.19 no.3
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• pp.893-901
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• 2008

The disconfirmation paradigm is the earliest researched and the most deeply researched of all the paradigms in marketing. Disconfirmation paradigm deals with the influence of expectation, perceived product performance, and the discord between the two on consumer satisfaction. The GAP-Model is based on the disconfirmation paradigm that tries to understand the effect of the gap between before purchase expectations and after purchase perceptions of the product performance on dependent variables such as customer satisfaction. The purpose of this research is to test whether regression coefficients of a P-Model(performance only model), an E-Model(expectation only model) and GAP(P-E)-Model are equivalent in explaining service value and loyalty. The Chow's F-Test is used to test the excellence of the 3 models. As a result of comparison and analysis, P-Model showed more excellence of service value and loyalty than E-Model or GAP-Model.

• Journal of Information Technology Services
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• v.12 no.2
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• pp.31-53
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• 2013

Web 2.0 has affected existing e-commerce and created a new business model of e-commerce, known as social commerce. Social commerce is a subset of e-commerce using social network services and is emerging as an important platform due to increased popularity of social networking services. This study focuses on analyzing the factors that influence the shopping value and intention to repurchase of social commerce users. Based on prior researches, we develop a research model, including individual characteristics of social commerce users (Collectivism, Price Sensitivity, Impulse Buying) and social commerce characteristics (Cost saving, Product Variety, Shopping Convenience). Furthermore, this study proposed the moderating effect of Perceived Security and the relationship between shopping value and intention to repurchase. To empirically validate, the data were collected from 220 social commerce users. The results indicated that individual characteristics (collectivism, price sensitivity, impulse buying) were positively related to hedonic shopping value. In addition, social commerce characteristics (cost saving, shopping convenience) were positively related to utilitarian value. The shopping value(hedonic and utilitarian) had a significant influence on intention to repurchase. The moderating effects of perceived security also was significant. Lastly, the implications for theory and practice are discussed.

• The Journal of Industrial Distribution & Business
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• v.13 no.4
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• pp.35-49
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• 2022

Purpose - According to the recently changing consumer smart environment and consumer decision-making process, this study investigates the structural relationship between electronic(online) WOM information characteristics and brand community experience value types on specific brand reliability and brand transformation. In particular, the characteristics of word of mouth information and the experience value of brand community users were divided into detailed fac tors and approached. Methodology - In order to proceed with this study, we review previous studies and setting hypotheses. The hypothesis was verified through a survey that was conducted for the consumers with online consumption activities in less than six months. With reference to previous studies, operational definition was made for the questionnaire design. In order to verify the hypothesis, 282 people were statistically analyzed through the survey This data were used for AMOS for confirm hypothesis established. Results - eWOM information characteristics were classified into usefulness, timeliness and un-bias, and online community experience values were classified into interaction, playfulness, and virtuality. In addition, it is to investigate the relationship between the brand reliability and user's experience value in brad community. The main results are as follows. The first result was that usefulness and un-bias, which are the eWOM information characteristics had a positive effect on forming brand reliability. However, the factor of timeliness did not affect brand reliability. Second, in terms of user experience value and brand reliability in the brand community. It was fo und that experience values such as interaction, playfulness, and vituality all had a positive influence on brand reliability. Third, it was found that brand reliability has a positive influence on the on-line conversion activity of users. Conclusions - Through this study, the field of online consumer behavior research is expanding, and this study suggested that careful management is necessary according to the type or characteristics of eWOM information. Additionally, it presents the importance of the user's empirical value in the brand community influencing brand attitude and reliability. In practice, the implementation of the marketing communication mix in digital marketing has recently been underway to enhance the conversion behavior of users. At this level, it also reveals the preceding factors that increase user conversion behavior.

• Journal of Information Technology Services
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• v.20 no.4
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• pp.1-21
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• 2021

At a time when the e-commerce market is experiencing accelerated growth, with advancements in information and communications technology (ICT), the problems of distribution of counterfeit products and consumer confusion caused by non-face-to-face purchases have increased. Hence, amid intensifying competition, it has become important for e-commerce companies deliver product information more efficiently, provide differentiated services, and secure credibility for consumers by reducing consumer damage from buying counterfeit products. However, even though consumer confusion and the inadvertent purchase of counterfeit products are intensifying in such a market scenario, there are no services that aim to solve such problems. This study examines the conventional e-commerce industry in South Korea through a political, economic, social, and technological (PEST) analysis, based on in-depth interviews with consumers, to derive the pain and gain points of the industry. As a result, the inherent problems of the e-commerce industry were revealed. Through a service value network perspective, services aimed at resolving such issues were derived, and the e-commerce business ecosystem needed to solve this problem was deduced. The findings revealed that the artificial intelligence-based service support platform has become a major driving force within the e-commerce innovation ecosystem by enabling a new way to create and secure value using ICT. This entails a new exchange mechanism and transaction architecture and a new organizational structure that breaks the barriers between industries.