• The Journal of Advanced Prosthodontics
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• v.1 no.2
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• pp.85-90
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• 2009

STATEMENT OF PROBLEM. Over the years, resin-bonded fixed partial dentures (RBFPDs) have gone through substantial development and refinement. Several studies examined the biomechanics of tooth preparation and framework design in relation to the success rate of RBFPDs and considered retention and resistance form essential for increase of clinical retention. However, these criteria required preparations to be more invasive, which violates not only the original intentions of the RBFPD, but may also have an adverse effect on retention due to loss of enamel, an important factor in bonding. PURPOSE. The object of this in vitro study was to compare the dislodgement resistance of the new types of RBFPDs, the conventional three-unit fixed partial denture, and conventional design of RBFPD (Maryland bridge). MATERIAL AND METHODS. Fifty resin mandibular left second premolars and second molars were prepared on dentiforms, according to the RBFPD design. After model fabrication (five group, n = 10), prostheses were fabricated and cemented with zinc phosphate cement. After cementation, the specimens were subjected to tensile loading at a cross head speed of 4 mm/min in a universal testing machine. The separation load was recorded and analyzed statistically using one-way analysis of variance followed by Duncan's multiple range test. RESULTS. Group V, the pin-retained RBFPDs, had the highest mean dislodgement resistance, whereas specimens of group II, the conventional RBFPDs, exhibited a significantly lower mean dislodgement resistance compared to the other 4 groups (P <.05). There were no significant differences between group I, III, and IV in terms of dislodgement resistance (P>.05). Group V had the highest mean MPa (N/$mm^2$) (P <.05). There was no significant difference between groups I, II, III and IV (P > .05). CONCLUSION. Within the limits of the design of this in vitro study, it was concluded that: 1. The modified RBFPDs which utilizes the original tooth undercuts and requires no tooth preparation, compared with the conventional design of RBFPDs, has significantly high dislodgement resistance (P < .05). 2. The modified RBFPDs which utilizes the original tooth undercuts and requires minimal tooth preparation, compared with the conventional FPDs, has significantly no difference in retention and dislodgement resistance)(P>.05). 3. The pin-retained FPDs showed a high dislodgement resistance compared to the conventional three-unit FPDs (P<.05).

• The Journal of Advanced Prosthodontics
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• v.1 no.2
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• pp.63-67
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• 2009

STATEMENT OF PROBLEM. Use of custom tray and tray adhesive is clinically recommended for elastomeric impression material. However there is not clear mention of drying time of tray adhesive in achieving appropriate bonding strength of tray material and impression material. PURPOSE. This study is to investigate an appropriate drying time of tray adhesives by evaluating tensile bonding strength between two types of polyvinylsiloxane impression materials and resin tray, according to various drying time intervals of tray adhesives, and with different manufacturing company combination of impression material and tray adhesive. MATERIAL AND METHODS. Adhesives used in this study were Silfix (Dentsply Caulk, Milford, Del, USA) and VPS Tray Adhesive (3M ESPE, Seefeld, Germany) and impression materials were Aquasil Ultra (monophase regular set, Dentsply Caulk, Milford, Del, USA) and Imprint II Garant (regular body, 3M ESPE, Seefeld, Germany). They were used combinations from the same manufacture and exchanged combinations of the two. The drying time was designed to air dry, 5 minutes, 10 minutes, 15 minutes, 20 minutes, and 25 minutes. Total 240 of test specimens were prepared by auto-polymerizing tray material(Instant Tray Mix, Lang, Wheeling, Il, USA) with 10 specimens in each group. The specimens were placed in the Universal Testing machine (Instron, model 3366, Instron Corp, University avenue, Nowood, MA, USA) to perform the tensile test (cross head speed 5 mm/min). The statistically efficient drying time was evaluated through ANOVA and Scheffe test. All the tests were performed at 95% confidence level. RESULTS. The results revealed that at least 10 minutes is needed for Silfix-Aquasil, and 15 minutes for VPS Tray Adhesive-Imprint II, to attain an appropriate tensile bonding strength. VPS Tray Adhesive-Imprint II had a superior tensile bonding strength when compared to Silfix-Aquasil over 15 minutes. Silfix-Aquasil had a superior bonding strength to VPS Tray Adhesive-Aquasil, and VPS Tray Adhesive-Imprint II had a superior tensile bonding strength to Silfix-Imprint II at all drying periods. CONCLUSION. Significant increase in tensile bonding strength with Silfix-Aquasil and VPS Tray adhesive-Imprint II combination until 10 and 15 minutes respectively. Tray adhesive-impression material combination from the same company presented higher tensile bonding strength at all drying time intervals than when using tray adhesive-impression material of different manufactures.

• Journal of Intelligence and Information Systems
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• v.19 no.4
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• pp.1-10
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• 2013

Personalization aims to provide customized contents to each user by using the user's personal preferences. In this sense, the core parts of personalization are regarded as recommendation technologies, which can recommend the proper contents or products to each user according to his/her preference. Prior studies have proposed novel recommendation technologies because they recognized the importance of recommender systems. Among several recommendation technologies, collaborative filtering (CF) has been actively studied and applied in real-world applications. The CF, however, often suffers sparsity or scalability problems. Prior research also recognized the importance of these two problems and therefore proposed many solutions. Many prior studies, however, suffered from problems, such as requiring additional time and cost for solving the limitations by utilizing additional information from other sources besides the existing user-item matrix. This study proposes a novel implicit rating approach for collaborative filtering in order to mitigate the sparsity problem as well as to enhance the performance of recommender systems. In this study, we propose the methods of reducing the sparsity problem through supplementing the user-item matrix based on the implicit rating approach, which measures the trust level among users via the existing user-item matrix. This study provides the preliminary experimental results for testing the usefulness of the proposed model.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.588-590
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• 2013

This study aims to explore and understand better how consumers' value orientation relates to consumer's intention to use and Word-of-Mouth behaviors in using Web sites. Consumers have perceptions of the shopping value they acquire during their experiences in navigating Web sites. This consumer's shopping value is considered as utilitarian shopping value, information shopping value, and hedonic shopping value. The current paper proposes that value orientation of consumers in Web sites would consequently affect consumer attitude such as intention to use and Word-of-Mouth. In addition, the research investigates the moderating effect of consumer's personality between consumer's shopping value and consumers' attitude in Web sites. For testing the hypothesized research model, survey and Lisrel analysis are conducted. The findings emphasize that online providers need to focus on the perceived values most salient to consumers in order to improve their profitability. Furthermore, providers may also identify the reason why consumers perceive these values much lower when using the Web sites.

• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.2999-3005
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• 2009

Among the more than 120 different types of human papillomavirus (HPV), types 16 and 18 have been known to be high risk agents that cause cervical cancer. We examined, in an immuno-chromatographic analysis, the potential of using the early gene product, E7 protein, as a diagnostic marker of cervical cancer caused by HPV. We developed monoclonal antibodies specific to HPV-16 and 18 E7 proteins that were produced from bacterial cells using gene recombinant technology. For each E7 protein, the optimal antibody pair was selected using the immuno-chromatographic sandwichtype binding system based on the lateral flow through membrane pores. Under these conditions, this rapid testing assay had a detection capability as low as 2 ng/mL of E7 protein. Furthermore, since viral analysis required the host cell to be lysed using chemicals such as detergents, it was possible that the E7 protein was structurally damaged during this process, which would result in a decrease in detection sensitivity. Therefore, we examined the detrimental effects caused by different detergents on the E7 protein using HeLa cells as the host. In these experiments, we found that the damage caused by the detergent, nonylphenylpolyethylene glycol (NP-40), was minimal relative to Triton X-100 commonly used for the cell lysis. Temperature also affected the stability of the E7 protein, and we found that the E7 protein was stabilized at 4$^{\circ}C$ for about 2 h, which was 4 times longer than at room temperature. Finally, a HPV-infected cervical cancer cell line, which was used as a real sample model, was treated using the optimized conditions and the presence of E7 proteins were analyzed by immuno-chromatography. The results of this experiment demonstrated that this rapid test could specifically detect HPV-infected samples.

• Journal of Digital Convergence
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• v.12 no.10
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• pp.201-209
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• 2014

The purpose of this study is to analyze subjective and objective factors for the successful operation of One-Person Creative Firms and find significant variables in accordance with the sales and net profit that are representing business performances. Additionally, we were trying to find that what One-Person Creative Firms have had a government assistance need the supports in order to achieving a good performance in sales and net profit. In the result of this study, the sales volume is related that two(2) subjective(Judgment, Planning) and four(4) objective factors(Patent Application, Patent Registration, Business Duration, Initial Capital). The net profit is related that Challenging Spirits in subjective factors and Run-up to the Business, Business Duration, Initial Capital in objective factors. Ultimately, these factors are important variables for the sales and net profit in relationship both the positive(+) and negative(-). This is an exploratory nature of the study rather than the rigorous hypothesis testing. Therefore, a rigorous hypothesis test study model to derive a more detailed study is needed based on the results of this study in the future.

• Korean Journal of Environment and Ecology
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• v.21 no.5
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• pp.449-455
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• 2007

To offer basic data for restoration technology development of the evergreen broad-leaved forest, this researcher did monitoring on the restoration project of the evergreen broad-leaved forest implemented in Dadohaesang(Marine) National Park for three years starting the year 2005, As a result of the monitoring job of tree height and survival rate of the evergreen broad-leaved forest on the 5 model afforestation-testing sites subsequent to the slanting surface, size of island, and whether the pastured livestock exist or not, it was found that the tree height & survival rate of the evergreen broad-leaved trees planted on the ridge parts of the southwest slanting surface were in better condition than those of the evergreen broad-leaved trees planted on the ridge parts of the northeast slanting surface. The survival rate of the evergreen broad-leaved tree planted on a big island was revealed to be higher than that of the evergreen broad-leaved tree planted on a small island. In addition, the survival rate of the evergreen broad-leaved tree planted in a place where livestock was pastured was revealed to be much lower than that of the evergreen broad-leaved tree planted in a place where there was no livestock. Conclusively, there showed a good tree hight and survival rate of the evergreen broad-leaved tree planted on the ridge parts of the southwest slanting surface, on a big island, and at the place where there was no pastured livestock.

• Interdisciplinary Bio Central
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• v.4 no.3
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• pp.10.1-10.12
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• 2012

Introduction: We investigated frameshift suppressor tRNAs previously reported to use five-base anticodon-codon interactions in order to provide a collection of frameshift suppressor tRNAs to the synthetic biology community and to develop modular frameshift suppressor logic devices for use in synthetic biology applications. Results and Discussion: We adapted eleven previously described frameshift suppressor tRNAs to the BioBrick cloning format, and built three genetic logic circuits to detect frameshift suppression. The three circuits employed three different mechanisms: direct frameshift suppression of reporter gene mutations, frameshift suppression leading to positive feedback via quorum sensing, and enzymatic amplification of frameshift suppression signals. In the course of testing frameshift suppressor logic, we uncovered unexpected behavior in the frameshift suppressor tRNAs. The results led us to posit a four-base binding hypothesis for the frameshift suppressor tRNA interactions with mRNA as an alternative to the published five-base binding model. Conclusion and Prospects: The published five-base anticodon/codon rule explained only 17 of the 58 frameshift suppression experiments we conducted. Our deduced four-base binding rule successfully explained 56 out of our 58 frameshift suppression results. In the process of applying biological knowledge about frameshift suppressor tRNAs to the engineering application of frameshift suppressor logic, we discovered new biological knowledge. This knowledge leads to a redesign of the original engineering application and encourages new ones. Our study reinforces the concept that synthetic biology is often a winding path from science to engineering and back again; scientific investigations spark engineering applications, the implementation of which suggests new scientific investigations.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.12 no.4
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• pp.121-131
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• 2017

The most important points in the field of entrepreneurship research are new venture creation and behaviors for start-up venture. Most of past researches are limited to the formation of entrepreneurial intention, and researches on entrepreneurial activities, specifically nascent entrepreneurial behavior, have not been studied well. In this study, we view entrepreneurial process as gestation process from entrepreneurial intention to nascent entrepreneurial activities, and identify the moderating effects of cognitive style, which is the way of thinking about the information in entrepreneurial process. In addition, we find the moderating effects of cognitive style on the relationships between perceived barriers and support in environmental factors and nascent entrepreneurial activities. Subjects of this study are potential entrepreneurs. So we selected university students who are taking venture start-up course, conducted a survey, collected 367 questionnaires. In statistical test, we applied PLS-SEM for testing hypotheses because CB-SEM is too sensitive to test more than two moderating effects in th research model. As a result of the analysis, it was found that entrepreneurial intention, cognitive planning style, cognitive creative style, perceived support had a significant effect on nascent entrepreneurial behavior. The results of the analysis of the moderating effects of cognitive style which are the hypotheses in the research are as follows. First, the cognitive planning style did not have a significant moderating effect on the relationship between entrepreneurial intention and nascent entrepreneurial activities. Second, in the relationship between perceived barriers and nascent entrepreneurial activity, cognitive planning style did not have significant moderating effect, and cognitive creating style had significant negative moderating effect. Third, in the relationship between perceive support and nascent entrepreneurial activity, cognitive planning style had significant positive moderating effect, and cognitive creating style did not have significant moderating effect.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.2
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• pp.443-453
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• 2013

The hybrid test is one of the most advanced test methods to predict the structural dynamic behavior with the interaction between a physical substructure and a numerical modeling in the hybrid control system. The purpose of this study is to perform the multi-directional dynamic test of a steel frame structure with the real-time hybrid system and to evaluate the validation of the results. In this study, FEAPH, nonlinear finite element analysis program for hybrid only, was developed and the hybrid control system was optimized. The inefficient computational time was improved with a fixed number iteration method and parallel computational techniques used in FEAPH. Furthermore, the previously used data communication method and the interface between a substructure and an analysis program were simplified in the control system. As the results, the total processing time in real-time hybrid test was shortened up to 10 times of actual measured seismic period. In order to verify the accuracy and validation of the hybrid system, the linear and nonlinear dynamic tests with a steel framed structure were carried out so that the trend of displacement responses was almost in accord with the numerical results. However, the maximum displacement responses had somewhat differences due to the analysis errors in material nonlinearities and the occurrence of permanent displacements. Therefore, if the proper material model and numerical algorithms are developed, the real-time hybrid system could be used to evaluate the structural dynamic behavior and would be an effective testing method as a substitute for a shaking table test.