• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.10
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• pp.4034-4053
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• 2015

In order to meet various requirements for transmission quality of both primary users (PUs) and secondary users (SUs) in cognitive radio networks, we introduce a channel bonding mechanism for PUs and a channel reservation mechanism for SUs, then we propose a novel spectrum allocation strategy. Taking into account the mistake detection and false alarm due to imperfect channel sensing, we establish a three-dimensional Markov chain to model the stochastic process of the proposed strategy. Using the method of matrix geometric solution, we derive the performance measures in terms of interference rate of PU packets, average delay and throughput of SU packets. Moreover, we investigate the influence of the number of the reserved (resp. licensed) channels on the system performance with numerical experiments. Finally, to optimize the proposed strategy socially, we provide a charging policy for SU packets.

• Journal of Information Technology Applications and Management
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• v.29 no.4
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• pp.35-49
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• 2022

Knowledge sharing occurs through voluntary interactions between human actors. In this paper, from the perspective of social interaction, the effect of transactive memory capability and social capital (bridging social capital and bonding social capital) on knowledge sharing intention was analyzed, and tenure was demonstrated as a moderating factor that can strengthen their relationship. Therefore, the results of this study are summarized as follows. First, it was verified that the transactive memory capability had a significant positive effect on the knowledge sharing intention. Second, it was found that the bridging social capital and bonding social capital held by individuals had a significant positive effect on knowledge sharing intention. Social capital is understood to form an individual's voluntary motivation for knowledge sharing. Third, it was verified that the moderating effect of tenure suggested in this study was not significant. Based on the results of this study, implications and future research directions were presented.

• Nuclear Engineering and Technology
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• v.51 no.5
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• pp.1333-1344
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• 2019

An integrated approach of model simplification for high burnup spent nuclear fuel is proposed based on material calibration using optimization. The spent fuel rods are simplified into a beam with a homogenous isotropic material. The proposed approach of model simplification is applied to fuel rods with two kinds of interfacial configurations between the fuel pellets and cladding. The differences among the generated models and the effects of interfacial bonding efficiency are discussed. The strategy of model simplification adopted in this work is to force the simplified beam model of spent fuel rods to possess the same compliance and failure characteristics under critical loads as those that result in the failure of detailed fuel rod models. It is envisioned that the simplified model would enable the assessment of fuel rod failure through an assembly-level analysis, without resorting to a refined model for an individual fuel rod. The effective material properties of the simplified beam model were successfully identified using the integrated optimization process. The feasibility of using the developed simplified beam models in dynamic impact simulations for a horizontal drop condition is examined, and discussions are provided.

• The Journal of the Korea Contents Association
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• v.12 no.1
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• pp.460-475
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• 2012

The relationship between Korean bank and customer are known as rigidity compare to other industry. The conservative organizational culture is often found in Korean banks. Today, Korean banks are facing dramatic change in digital world in that new wave in online intensifies the connectivity with bank customers and potentials. The introduction of social media would force to develop new marketing strategy in terms of the relationship oriented behavior. The case study presents the findings of a social media marketing strategy which was conducted in Industrial Bank of Korea in 2009-2011. More specifically, the study was designed to determine and evaluate the importance of social media marketing by retail bank in strategic instrument. Also it sets out to determine the perceived usefulness of the relationship oriented services offered by banks to their visitors and followers what these banks can do in order to improve bank services to improve competitive. Using the six relationship activity factors, the banks were examined in the study, a set of core activities (trusty worthy, empathy, shared value, emotional bonding, rich communication) are defined and described.

• Restorative Dentistry and Endodontics
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• v.46 no.4
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• pp.55.1-55.9
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• 2021

Objectives: The purpose of this systematic review was to collect and discuss the technique of adhesive systems application on dentin substrate under electric current. Materials and Methods: The first search strategy was based on data available at PubMed, LILACS, Scielo, Scopus, and Cochrane Library, using a combination of descriptors such as "dentin bond agents OR adhesive system AND electric current OR electrobond" or "dentin bonding agents OR dentin bonding agent application OR adhesive system AND electric current OR electrobond", with no limit regarding the publication year. The second search strategy was based on the articles' references found previously. An additional search strategy was applied that concerned the proposed theme in the SBU-UNICAMP (Unicamp's Library System Institutional Repository). Results: Twelve studies published between 2006 and 2020 were found. The analyses of the selected studies showed that the use of electric current during adhesive systems application on dentin, whether conventional or self-conditioning, increases resinous monomer infiltration in the dentin substrate, which improves the hybridization processes and the bond strength of the restorative material to dentin. Conclusions: Despite the favorable results related to the use of this technique, there is still no specific protocol for the application of adhesive systems under electric current.

• Journal of Information Technology Applications and Management
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• v.14 no.2
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• pp.129-149
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• 2007

The purpose of this study is to examine the effect of relationship orientation factors on customer satisfaction and loyalty in Internet shopping malls. Based on previous exploratory work and a review of the literature of relationship marketing, six key factors of relationship orientation construct are identified: trust, bonding, communication. shared value. empathy and reciprocity. And a conceptual model is developed and seven research hypotheses are empirica1ly examined using structural equation modelling. The results show that bonding, shared value and reciprocity has statistically significant effect on the trust of online customers and trust has a positive influence on customer satisfaction and loyalty in Internet shopping malls. Theoretical. managerial and research implications are discussed.

• Journal of Distribution Research
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• v.13 no.2
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• pp.29-57
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• 2008

Empirical model was developed to test the building mechanism of trust dimensions and loyalty with the suppliers' bonding tactics to service firms. And interactive effects between suppliers' bonding tactics and service firms' store age was hypothesized in the trust-loyalty building processes. The model was tested in the context of animal clinics which belong to Korean Animal Hospital Association (KAHA). The data was analysed using structural equation model (SEM). The findings are as follows. First, two different relational bonding tactics play different roles in their effects on building trust dimensions toward suppliers. While supplier's social bonding tactic significantly influences on both the affective and cognitive trust of service firms, suppliers' structural bonding tactic only influences significantly on affective trust of service firms. Second, while suppliers' social bonding tactic influences on building service firms' loyalty significantly, suppliers' structural bonding tactic doesn't influence on building their loyalty. Suppliers' structural bonding tactic influences on building their loyalty indirectly through affective trust. Third, while service firms' affective trust influences on building loyalty significantly, cognitive trust doesn't. Their cognitive trust influences on building loyalty indirectly through affective trust. Fourth, the higher the firms' store age is, the more suppliers use social bonding tactics to build trust and loyalty directly. While the shorter the firms' store age is, the more suppliers partially use both the social and structural bonding tactics to build trust and loyalty. In conclusion, in the context of animal clinics' distribution channels, suppliers' relational bonding tactics with service firms differently influence to build trust sub-dimensions and loyalty. And, suppliers should take note of the interactive role of service firms' store age in the utilization of the different bonding tactics to build service firms' trust and loyalty toward suppliers. At the end of the paper, managerial implications, limitations, and future research directions are suggested.

• The Journal of Advanced Prosthodontics
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• v.11 no.6
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• pp.313-323
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• 2019

PURPOSE. Shear bond strength (SBS) test is the most commonly used method for evaluating resin bond strength of zirconia, but SBS results vary among different studies even when evaluating the same bonding strategy. The purpose of this study was to promote standardization of the SBS test in evaluating zirconia ceramic bonding and to investigate factors that may affect the SBS value of a zirconia/resin cement/composite resin bonding specimen. MATERIALS AND METHODS. The zirconia/resin cement/composite resin bonding specimens were used to simulate loading with a shear force by the three-dimensional finite element (3D FE) modeling, in which stress distribution under uniform/non-uniform load, and different resin cement thickness and different elastic modulus of resin composite were analyzed. In vitro SBS test was also performed to validate the results of 3D FE analysis. RESULTS. The loading flat width was an important affecting factor. 3D FE analysis also showed that differences in resin cement layer thickness and resin composite would lead to the variations of stress accumulation area. The SBS test result showed that the load for preparing a SBS specimen is negatively correlated with the resin cement thickness and positively correlated with SBS values. CONCLUSION. When preparing a SBS specimen for evaluating bond performance, the load flat width, the load applied during cementation, and the different composite resins used affect the SBS results and therefore should be standardized.

• Bulletin of the Korean Chemical Society
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• v.29 no.1
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• pp.197-201
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• 2008

Conformational heterogeneity of directly linked multiporphyrin arrays with larger molecular length retards their utilities in practical applications such as two-photon absorption and molecular photonic wire. In this regard, here we adopted a way to overcome the conformational heterogeneity through hydrogen bonding by selective binding of meso aryl substituents of porphyrins (host) with urea (guest) to form helical structure. Using steady-state and time-resolved spectroscopy, we observed the enhanced fluorescence quantum yield by ~1.8 to 2.4 times, enhanced anisotropy values and the disappearance of fast fluorescence decay component in the host-guest helical forms. In addition, the enhanced nonlinear optical responses of helical arrays infer the extended inter-porphyrin electronic coupling due to a significant change in dihedral angle between the neighboring porphyrin moieties. The current host-guest strategy will provide a guideline to improve the structural homogeneity of the photonic wire.

• Bulletin of the Korean Chemical Society
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• v.29 no.8
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• pp.1479-1484
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• 2008

Protein tyrosine phosphatase (PTP) 1B is the superfamily of PTPs and a negative regulator of multiple receptor tyrosine kinases (RTKs). Inhibition of protein tyrosine phosphatase 1B (PTP1B) has been proposed as a strategy for the treatment of type 2 diabetes and obesity. Recently, it has been reported that amentoflavone, a biflavonoid extracted from Selaginella tamariscina, inhibited PTP1B. In the present study, docking model between amentoflavone and PTP1B was determined using automated docking study. Based on this docking model and the interactions between the known inhibitors and PTP1B, we determined multiple pharmacophore maps which consisted of five features, two hydrogen bonding acceptors, two hydrogen bonding donors, and one lipophilic. Using receptor-oriented pharmacophore-based in silico screening, we searched the biflavonoid database including 40 naturally occurring biflavonoids. From these results, it can be proposed that two biflavonoids, sumaflavone and tetrahydroamentoflavone can be potent allosteric inhibitors, and the linkage at 5',8''-position of two flavones and a hydroxyl group at 4'-position are the critical factors for their allosteric inhibition. This study will be helpful to understand the mechanism of allosteric inhibition of PTP1B by biflavonoids and give insights to develop potent inhibitors of PTP1B.