• International Journal of Air-Conditioning and Refrigeration
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• v.8 no.1
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• pp.50-61
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• 2000

The effects of an inserted coil on flow . patterns and heat transfer performance for a horizontal rotating heat pipe have been studied experimentally. Especially, the present study is to see an internally inserted helical coil inside a RHP would lead to the same kind of results as internal fins. Visualization test conducted for an acryl tube, charged water with at a volumetric rate of 20%. When the flow kept pool regime at a low rpm(less than 1,000rpm), the movement of coil forced the water to flow in axial direction. But this pumping effect of coil disappeared, when the pool regime changed to annular one which could be created by increasing rpm. The pumping effects for RHP with an inserted coil resulted in the enhancement in both condensation heat transfer coefficient and heat transport limitation, as obtained in case of using internal fins. But all these effects became negligible in the range of higher rpm(above 1,000-1,200) with the transition of flow regime to annular flow.

• The korean journal of orthodontics
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• v.18 no.1 s.25
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• pp.25-53
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• 1988

Retraction of canines represents a fundamental stage in a considerable number of orthodontic treatment. Correct position of the canine after retraction is most important for function, stability, and esthetics. The purpose of this study was to investigate the stress in the periodontal tissue at the initial phase during canine retraction using various types of sectional retraction springs, by finite element method. Three dimensional model of tooth, periodontal ligament, bone and eight springs were simulated and tested. The following results were obtained. 1. In sectional retraction springs, increasing number of helix and the closed loop in preference to the open loop provided an decrease in horizontal force. Without angulating the arms of spring, the T-loop revealed the highest Moment-to-force ratio. 2. The Moment-to-force ratio raised by angulating mesial and distal arms of spring, but very large horizontal force was applied to canine. 3. When optimal force and optimal moment was applied to canine, the stress induced was homogeneous and the difference of stress value from cervix to the apex was little.

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1401-1406
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• 2013

This study tested the feasibility of observing H/D exchange of intact protein by top-down electron capture dissociation (ECD) mass spectrometry for the investigation of protein structure. Ubiquitin is selected as a model system. Local structural information was obtained from the deuteration levels of c and $z^{\cdot}$ ions generated from ECD. Our results showed that ${\alpha}$-helix region has the lowest deuteration level and the C-terminal fraction containing a highly mobile tail has the highest deuteration level, which correlates well with previous X-Ray and HDX/NMR analyses. We studied site-specific H/D exchange kinetics by monitoring H/D exchange rate of several structural motives of ubiquitin. Two hydrogen bonded ${\beta}$-strands showed similar HDX rates. However, the outer ${\beta}$-strand always has higher deuteration level than the inner ${\beta}$-strand. The HDX rate of the turn structure (residues 8-11) is lower than that of ${\beta}$-strands (residues 1-7 and residues 12-17) it connects. Although isotopic distribution gets broader after H/D exchange which results in a limited number of backbone cleavage sites detected, our results demonstrate that this method can provide valuable detailed structural information of proteins. This approach should also be suitable for the structural investigation of other unknown proteins, protein conformational changes, as well as protein-protein interactions and dynamics.

• Journal of Contemporary Eastern Asia
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• v.16 no.2
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• pp.20-43
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• 2017

While the Internet has been used to galvanise people for the collective good, many have voiced concerns over the noise and vitriol present online and polarisation. In Singapore where the government regulates traditional mainstream media such as print and broadcast, the online space has been described as a "Wild Wild West" rife with rumours, untruths and misinformation. Such developments do not only exert a potential negative effect on the deliberative nature of public discourse but also skew bias towards the online space, affecting the ability of online users to communicate with authority and power. This study seeks to examine the rationality of the cyberspace through using a new "rationality" framework to analyse political discourse online. Comprising objectivity, emotionality and partisanship, the rationality framework was applied to a content analysis of 197 blogs with political content in 2014. The analysis indicated that the online political space was not the Wild Wild West that it was touted to be with significant levels of objectivity and non-partisanship. There was a stark absence of emotional discourse, and relationships were observed between bloggers' anonymity and rationality. Cognisant of academia's and policymakers' interest on the quality and effects of online discourse, the proposed analytical framework and the study findings hold implications for both developed and developing countries.

• Journal of Contemporary Eastern Asia
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• v.16 no.2
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• pp.44-58
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• 2017

Scholars have long debated the factors that drive political participation and have recently applied theories, developed from analyses of citizens from Europe and the United States, to respondents in the democratizing countries of Asia. In both Hong Kong and Singapore, however, citizens attend rallies and contact officials - yet do so under authoritarian governance. Are the causes of political participation in these cities similar to what is observed in other groups of respondents across Asia? Or, do institutions influence whether individuals participate? In this paper, I evaluate the development of liberal norms of engagement in both cities as a function of traditional models of participation. As citizens in these cities possess some of the highest standards of living in the region, they should also face frustrations with the limited democratic accountability of their leaders. Ultimately, individuals in each city have developed support for democracy but, given the differing goals of each regime, the nature of democratic engagement differs considerably. In Singapore, citizens are mobilized to engage and participate but support the status quo. By contrast, engaged Hong Kong residents participate out of a frustration with the government, a function of their high levels of internal efficacy and institutional detachment.

• Journal of Contemporary Eastern Asia
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• v.16 no.2
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• pp.3-19
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• 2017

"Knowledge worker" is a term used to describe highly educated people whose role in the workforce involves the use of information and knowledge. Knowledge workers are key to the success of a great many organizations. Many Chinese companies find that the voluntary turnover rate among their knowledge workers is high. The purpose of this paper is to explore, from the perspective of knowledge workers and the characteristics peculiar to them, the factors that influence this high voluntary turnover rate. The models used in this paper, that will enable understanding of the characteristics of knowledge workers in China, are the Chinese Personality Assessment Inventory and the Five Factors Model. In the case of Huawei, analysis using these models leads to the conclusion that the main factors that influence the voluntary turnover of knowledge workers in China are: age; gender; degree of extraversion and how open the person is to new experiences; family orientation; and occupation. This study leads to the conclusion that the company should pay closer attention to three groups: female employees who put a high value on their families; employees from non-R&D departments; and younger employees who show a high degree of openness to new experiences.

• Journal of Contemporary Eastern Asia
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• v.16 no.2
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• pp.93-109
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• 2017

Cross-culturally, acts of sharing are recognized as an effective method to initiate and maintain human relationships in real-life situations by promoting continuous reciprocal exchanges between donors and recipients. Specifically, this study examines the effects of sharing a media product from the perspective of the givers, as compared to effects on the receivers. "Gangnam Style," a Korean music video, is of interest because it was spontaneously shared worldwide by young adults who used it as a vehicle to build and strengthen social relationships, among young adults. While both the givers and receivers of the "Gangnam Style" benefited from bridging new relationships, the results of this study found that those who gave "Gangnam Style" benefited more in terms bonding already existing relationships, compared to those who received materials. This study provides further evidence in support of the "sender-effect" paradigm and enhances our understanding of how online sharing contributes to the construction of social capital among the young adults.

• Journal of Service Research and Studies
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• v.3 no.1
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• pp.55-73
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• 2013

The purpose of this research is to find a solution for matching service between recruiting and job seeking of software developers. An efficient matching service solution is essential for acquiring solid global competitiveness in software industry and IT academia. An in-depth analysis on deep-rooted problems on mismatching has been performed. Past and present policies on mismatching solutions have been reviewed based on desirable co-growth structure. A new matching solution has been derived and a triple-helix strategy has been suggested. A survey result for 14 domain experts and 85 employees of large and small software companies shows that the suggested matching solution is useful. The results of this research can be used for finding a better matching service solution and policies.

• Proceedings of the Microbiological Society of Korea Conference
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• 2006.05a
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• pp.66-68
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• 2006

SUF machinery in Echerichia coli, responsible for the biosynthesis of iron-sulfur clusters, is composed of six protein components (SufABCDSE), among which SufB, SufC, and SufD associate in a complex. We have determined the structures of SufA, SufC, and SufD by X-ray crystallography. SufA is a dimer, in which C-terminal segments containing essential cysteine residues (Cys-Gly-Cys) are positioned to allow coordination of an Fe-S cluster and/or an Fe atom. SufC has the overall structure similar to that of ABC-ATPase but takes an inactive form. SufD has a ${\beta}-helix$ flanked with a-helical domains. We also studied the functional roles of the residues in SufD by mutagenesis and determined the crystal structure of SufCD complex. Molecular mechanism of Fe-S cluster biosynthesis is discussed on the basis of the structural and functional evidence.

• Microbiology and Biotechnology Letters
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• v.28 no.4
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• pp.195-201
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• 2000

Glucoamylase of Saccharomyces diastaticus is produced as a large precursor composed of signal peptide (21 amino acid residues), Thr and Ser-rich region and functional glucoamylase. To evaluate the utility of the glucoamylase signal peptide (GSP) for the secretion of foreign proteins, four types of GSP mutants (ml : Pro-18 longrightarrowLeu-18, m2 : Tyr-13 longrightarrowLeu, m3 : Ser-9longrightarrowLeu-9, m4 : Asn-5 longrightarrowPro-5) were constructed and secretion efficiency of each mutant was compared with that of native GSP by the expression and secretion of Bacillus subtilis CMCase under the control of GAP in N-terminal domain and hydrophobic domain. n mutant 4, a polar amino acid was replaced by a helix - breaking Pro residue. CMCase activity assay and Western blot analysis revealed that CMCase secretion by GSP mutants replaced by Leu were increased compared with native GSP. In the case of m2 and m3, the substitution of Leu for Tyr-13 and Ser-9 in the hydrophobic region resulted in a twofold increase in the extracellular CMCase activity.