• Journal of The Korean Association For Science Education
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• v.21 no.2
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• pp.279-288
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• 2001

In this study, interaction patterns in peer small-group discussions with cognitive conflict strategy (CCS) and those with social consensus strategy (SCS) were compared. Verbal interactions of four small groups (16 students) in learning science concepts were analyzed at the levels of turns, interaction units, and episodes. The frequencies of total turns and knowledge construction turns per discussion for the SCS group were higher than those for the CCS group. Comparing and evaluating hypotheses and discussion worksheets provided were especially effective in increasing metacognitive utterances of the SCS group students. The frequencies of 'most students participating mode', 'elaborative interaction mode', and 'exploratory episode' for the SCS group were higher than those for the CCS group. These suggested that more students in the SCS group participated in small-group discussions and their discussions were more interactive and elaborative. The interactions and episodes of the SCS group were also superior in quality to those of the CCS group.

• Informatization Policy
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• v.20 no.2
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• pp.20-38
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• 2013

Park, Keun-Hye government has just established a new ministry for integrating and managing the policies for science & technology and ICT. From the ICT governance perspective, the new ministry implies separating promotion policies from regulation polices. The current paper aims to present ICT policy implications by providing a perspective on regulation and promotion. A delphi survey was conducted for 32 experts in ICT sector. According to the experts, a clear distinction between regulation and promotion policies is difficult, and thus, integrating regulation and promotion policies looks more preferable. In general, an independent ministry that integrates regulation and promotion policies is mostly preferred. Some suggested an independent committee inside the ministry might be desirable, especially for the broadcasting regulation policy to be independent from the ministry control. The current study proposes tight collaboration between the newly established ICT ministry and the Korea Communications Commission, and in the long term, integrated administration of promotion and regulation policies. In particular, this study emphasizes the importance of the integrated policy management to enhance government policy capacity.

• Korean Chemical Engineering Research
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• v.44 no.6
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• pp.597-601
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• 2006

The degradation of the Nafion membrane by oxygen radical (OH, $HO_2$) was investigated in Polymer electrolyte membrane fuel cell (PEMFC). Nafion membrane was degraded in Fenton solution consisted with hydrogen peroxide (10-30％) and ferrous ion (1-4 ppm) at $80^{\circ}C$. After degradation in Fenton solution, C-F, S-O and C-O chemical bonds of membrane were broken by oxygen radical attack. Breaking of C-F bond reduced the mechanical strength of Nafion membrane, and hence induced pinholes, resulting in increase of $H_2$ crossover through the membrane. Decomposition of S-O and C-O bonds decreased the ion exchange capacity of the electrolyte membrane. The performance of unit cell composed the membrane, which was degraded in 30％ $H_2O_2$ with 4ppm $Fe^{2+}$ solution for 48 hr, was about half times as low as one with normal membrane.

• The Transactions of the Korean Institute of Power Electronics
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• v.6 no.5
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• pp.386-393
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• 2001

A series active power filter compensating current harmonics and unbalanced source voltages in a 3phase-3wire power system is presented. The system is composed of series active power filter and shunt passive filters that are tuned at 5th and 7th harmonics. The proposed series active power filter improves harmonic compensation characteristics of the shunt passive filters, reduces source side harmonic currents and compensates the unbalanced source voltages. In the proposed algorithm, compensation voltage for harmonic reduction is calculated by a performance function, and compensation voltage for the unbalanced source voltage is calculated based on the synchronous reference frame. Some results obtained from the experimental model using the proposed method are Presented to demonstrate and confirm its validity.

• Journal of Aerospace System Engineering
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• v.13 no.5
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• pp.49-56
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• 2019

The Long-Term Sustainability (LTS) guidelines have attracted the most attention in the recent formation of international norms of behavior regarding outer space activities. The discussion began at the U.N. COPUOS in 2010. In June 2019, the 21 guidelines were finally adopted. The guidelines include international cooperation to promote and support the observation of the situation of orbiting objects, including space debris, for the purpose of preserving the space environment indefinitely, sharing data and forecasts on space weather, and announcing each country's space policy in accordance with international law. Some guidelines have failed to reach a consensus as the mitigation of space debris is often difficult to separate from space weapons tests. As plans for small satellites and Rendezvous and Proximity Operations have been projected for the future, it is expected that each countries' position on preserving the space environment will become more acute.

• Clinical and Experimental Reproductive Medicine
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• v.36 no.3
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• pp.209-217
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• 2009

Objective: To analyze current issues and to propose alternatives for "the cryopreserved embryos generated before 2005". Methods: The differences in attitude among the stakeholders such as sperm donors, oocyte donors, and IVF clinics were presupposed. We want to forecast the impediments which occur inevitably in the process of "getting the informed consent" and "discarding the cryopreserved embryos generated before 2005". Results: Even though there is a specific guideline for "the cryopreserved embryos generated before 2005" at November 23, 2006, no consensus about the process related to "getting the informed consent" has been made. Conclusion: Unavoidably, it seems to be entering a period of massive discard of "the cryopreserved embryos generated before 2005". This is actually opposed to the intent of the Bioethics and Safety Act, which is to protect human dignity and prevent harm to human beings. We have to make reasonable due process to determine the destiny of "the cryopreserved embryos generated before 2005".

• The Journal of the Korea Contents Association
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• v.22 no.5
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• pp.633-642
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• 2022

This is conducted with the aim of critical discussions on existing arguments, focusing on the establishment of a higher lifelong learning ecosystem. First, this study discusses the characteristics of university education in Korea and the discourse on the crisis of local universities. Second, the arguments on the establishment of lifelong learning society and a lifelong learning system. Third, the arguments for the establishment of a higher lifelong learning ecosystem are reviewed and practical measures for this are critically discussed. The conclusion is as follows. Measures for the establishment of a higher lifelong learning ecosystem have been discussed in considerable detail, and through this, the possibility of overcoming the crisis of local universities and balanced regional development is sufficient. However, first, the university should play a central role, but this study questions whether university reform could be achieved to suit it. Second, in order to overcome the crisis, national responsibility, responsibility, and continuous support are required. On the other hand, it raised questions about whether cooperation from the current Korean government authorities is possible. Third, local communities should also achieve governance and participate in democratic ways, raising questions about whether a foundation-forming strategy for stakeholder consensus is established.

• The Journal of the Convergence on Culture Technology
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• v.9 no.5
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• pp.787-800
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• 2023

This paper is a study aimed at facilitating a comprehensive understanding of the music metaverse platform that will emerge in the era of Web 3.0 and exploring productive strategies for its construction. We examine the significance of the metaverse music platform from various perspectives and investigate the developmental process of digital music platforms from Web 1.0 to 3.0. Subsequently, assuming the emergence of metaverse platforms as a transition to Web 3.0, we align this transition with technological(VR technology, wearable devices, generative AI), cultural(digital avatars, fandom), and economic(NFT) discussions related to Web 3.0. These discussions are integrated with the developmental strategies of the metaverse music platform. Through this study, we hope to enhance the understanding of the metaverse music platform and provide insights into potential construction strategies.

• Journal of Venture Innovation
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• v.5 no.2
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• pp.101-110
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• 2022

It is easy for first movers of platform business model to monopolize the market due to the platform's own characteristics such as network effect and flywheel strategy. Accordingly, the regulations on platform operators are constantly being discussed in the recent monopoly regulation arguments, but the concrete regulations have not been settled worldwide. This is because there is no clear consensus on the valuation method which can objectively identify dominant platform firms from the others. This study suggested a platform valuation method based on the Tobin's Q theory, by measuring the moderating effect of the existence of specific scale of platform on the relationship between replacement cost and market valuation. Our method can not only be a standard for settling monopoly regulation by converging the regulation targets, but also contribute to active investment on the new platform firms by evaluating their potential growths quantitatively.

• The korean journal of orthodontics
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• v.26 no.2 s.55
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• pp.153-162
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• 1996

Rapid maxillary expansion is widely used for the correction of anteroposterior discrepancies, constriction of the maxillary arch, etc. This experiment was undertaken to examine the serial changes in the osteogenesis as well as the collagen fiber bundles in the intermaxillary suture during the rapid maxillary expansion treatment. Four young female dogs aged 6 to 8 months old and not showing menarche yet were used for the experiment. The maxillary impression of dogs were taken, expansion device cast and Hyrax screw soldered at the midline in the 1st premolar area. RME device was delivered to the dogs and the activation of 0.25 mm per quarter-turn was done 2 times per day for 10 days until 5 mm separation was made. Separation of the maxilla was confirmed by X-ray. The animals were sacrificed on 0, 15, 30, 60 days from the finish of maxillary separation and preparations for light microscopy and surface electron microscopy were made. The sutures were cut into frontal serial sections for examination of the histological reactions. The following results were obtained and the conclusions made. 1. The edges of the two palatal plates bordering the midpalatal suture which at the beginning of the retention period were mainly composed of compact bone, underwent extensive resorption followed by new bone formation and gradually became spongy bone rich in bone marrow which in the 60 day retention animal became the compact bone with short intermaxillary suture space. During this transformation, newly formed trabecular bone tissues were added to the original margin. 2. Throughout the expansion period, the collagen fibers underwent successive changes such as stretching, loss of polarity, and finally fibrillogenesis. Towards the end of the expansion procedure, sharpey's fiber formation in newly formed bones were observed. 3. Bony spicules were found in the initial stage of retention on occlusal topographic X-rays, which later were confirmed to have ossified. 4. Judging from the histological changes occuring during the experimental expansion, excessive expansion will cause an excessive bleeding, and retard the remodeling of intermaxillary suture. According to the above results, the bone remodeling after rapid maxillary expansion was preceded by the migration of migratory cells into the intermaxillary suture area. The bone remodeling phenomena were on-going during the 2 months retention sample.