• Korean Management Science Review
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• v.30 no.3
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• pp.1-16
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• 2013

In this paper, we deal with an enhanced index fund strategy by implementing the exchange trade funds (ETFs) within the context of the Black-Litterman approach. The KOSPI200 index ETF is used to build risk-controlled portfolio that tracks the benchmark index, while the proposed Black-Litterman model mitigates estimation errors in incorporating both active investment views and equilibrium views. First, we construct a Black-Litterman model portfolio with the active market perspective based on the momentum strategy. Then, we update the portfolio with the KOSPI200 index ETF by using the equilibrium return ratio and weighted averages, while devising optimization modeling for improving the information ratio (IR) of the portfolio. Finally, we demonstrate the empirical viability of the proposed enhanced index strategies with KOSPI 200 data.

• Imaging Science in Dentistry
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• v.30 no.1
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• pp.23-32
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• 2000

Purpose : The purpose of this study is to compare radiographic techniques for the diagnostic accuracy in the detection of osteophytes of the mandibular condyle. Material and Methods : A series of bone chips were placed at four locations on the condylar head of a dried human skull. Eight radiographic techniques such as panoramic, transcranial, infracranial, transorbital, reverse-Towne's, submentovertex, multidirectional tomographic and computed tomographic techniques were compared. Three oral radiologists were asked to rate the lesions by four stage score. The statistical analysis was performed by ANOVA test. Results: For the detection of lateral osteophyte, transcranial, infracranial, transorbital and reverse-Towne' s views showed superiority. Also, transcranial and infracranial views showed superiority for medial osteophyte. While for the detection of superior and anterior osteophyte, panoramic, transcranial, infracranial, transorbital views showed superiority. Lateral tomograph showed superiority for the detection of superior and anterior osteophyte, but it showed inferiority for lateral and medial osteophyte. And antero-posterior tomograph showed superiority for the detection of all osteophytes. Axial computed tomograph showed superiority for the detection of all osteophytes, and coronal computed tomograph showed superiority for lateral, medial and superior osteophytes. While reconstructed sagittal computed tomograph showed relatively superiority for the detection of anterior and superior osteophytes. Conclusion : The conventional radiographs can be used for the detection of bony changes of the mandibular condyle, and tomograph or computed tomograph can be used additionally when it is difficult to detect bony changes on conventional radiographs.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.9
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• pp.3146-3158
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• 2014

Efficient depth map coding is very crucial to the multi-view plus depth (MVD) format of 3-D video representation, as the quality of the synthesized virtual views highly depends on the accuracy of the depth map. Depth map contains smooth area within an object but distinct boundary, and these boundary areas affect the visual quality of synthesized views significantly. In this paper, we characterize the depth map by an auto-covariance analysis to show the locally anisotropic features of depth map. According to the characterization analysis, we propose an efficient depth map coding scheme, in which the directional discrete cosine transforms (DDCT) is adopted to substitute the conventional 2-D DCT to preserve the boundary information and thereby increase the quality of synthesized view. Experimental results show that the proposed scheme achieves better performance than that of conventional DCT with respect to the bitrate savings and rendering quality.

• Fashion & Textile Research Journal
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• v.26 no.3
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• pp.279-288
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• 2024

Fingernail-related content on YouTube is gaining popularity. This study aimed to present a new direction for nail content marketing and video production by identifying the current status of nail-related content on YouTube and factors affecting views. As for the research method, the study used the YouTube website, and the elements under analysis were classified into YouTuber characteristics (verbal characteristics, age group, gender, professional status, and celebrity status) and content characteristics (nail field, editing elements, and content). The results showed that standard language and terminology were generally used, and the proportion of YouTubers in their 30s was high. All nail-related content creators on YouTube were women, and they were found to be experts who worked as nail artists and nail content creators. As for the content characteristics, the proportion of art videos was high, and the video length was found mostly to be between 10 and 20 minutes. The editing elements included images, videos, and subtitles, and sound effects and background music were used frequently. Finally, it was found that the proportion of videos providing nail tips and know-how, product information, and procedures was high. This study identified factors that influence the number of views for nail videos. As a result, the study was able to present video production ideas for newcomers starting a nail-content YouTube channel, and this will be helpful in the development of nail content.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.53 no.1
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• pp.67-76
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• 2017

This study carried out and analyzed survey data on captains and mates of Korean coastal large trawlers in order to examine factors affecting body abnormalities and fatigue on bridge teams from work and environment at bridges of trawlers. The summarized result may be summed up as follows: multiple regression analysis with body pain and fatigue as dependent variables yields t-values of -2.559 (p<0.05) and -3.928 (p<0.05) respectively. From the result, environment at bridges (views, spaces and exhaust) were negative factors in affecting bridge workers' pain and fatigue. Thus, it is determined to secure available spaces to improve the workers' views through windows in front of, besides and rear bridge and create more pleasant atmospheric environment at bridge.

• Journal of The Korean Association For Science Education
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• v.28 no.6
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• pp.685-695
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• 2008

An analysis on the Inquiry unit of Science 10 textbooks was conducted in terms of nature of science (NOS). The subject of the analysis was instructional objectives, activities and sentences in the unit of ten Science 10 textbooks. Contents of the instructional objectives could be grouped into nature of science, nature of scientists, scientific methods, and Science-Technology-Society. The concrete nature of scientific knowledge (SK) and constructing scientific theory or model, however, were not found in the objectives. The total number of activities in the Inquiry unit was 38. Seventeen out of them were presented without any supplemental or introductory materials, and 21 activities were provided with information followed by questions, discussions or investigations. For the most activities, any clear statements about NOS elements and desired/informed views of NOS were not made. The sentences of the Inquiry units were mixed up with constructivist and inductive views on NOS. The definition of science tended to be described based on the inductive view. And the generation of SK tended to be described as discovering regularities in natural phenomena rather than constructing theories. For science teachers who want to teach NOS effectively, stating clear learning objectives and elements of NOS and presenting reading materials with relevant views on nature of science were necessary.

• Imaging Science in Dentistry
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• v.36 no.2
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• pp.103-109
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• 2006

Purpose : To evaluate position of the mandibular condyle within articular fossa in an asymptomatic population radiographically by a cone beam computed tomography. Materials and Methods : Cone beam computed tomography of 60 temporomandibular joints was performed on 15 males and 15 females with no history of any temporomandibular disorders, or any other orthodontic or prosthodontic treatments. Position of mandibular condyle within articular fossa at centric occlusion was evaluated. A statistical evaluation was done using a SPSS. Results : In the sagittal views, mandibular condyle within articular fossa was posteriorly located at medial and central sections. In the coronal views, mandibular condyle within articular fossa was laterally located at central section. Mandibular condyles in the right and left sides were showed asymmetric positional relationship at medial, central, and lateral sections. Conclusion : Mandibular condyle within articular fossa in an asymptomatic population was observed nonconcentric position in the sagittal and coronal views.

• Journal of The Korean Association For Science Education
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• v.26 no.3
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• pp.317-329
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• 2006

In this research, a questionnaire was developed to investigate high school students' viewpoints, originating from science history, on 'motion of on object', the subjects were seventy- five 10th grade students and sixty-five 11th grade students. Results found that the highest percentage among the types of 10th grade students' thoughts was related to the Middle Ages 'Impetus' viewpoints. Percentages of 11th grade students' thoughts were highest for Middle Ages and Newton views. These results provided proof that the development of student thoughts' based on science history' are consistent with school year. Furthermore, student thought regarding 'object motion' under the conditions of no force, vacuum, or air under a weightless stage were related to progressive viewpoints on science history. However, the percentage of thoughts related to earlier viewpoints were considerable. Student thoughts on parabolic motion, circle motion, and conservation amount of motion were found to be highly significant in similarity to the viewpoints of Galilei, Descartes, and Huygens; view cultivated before Newton. Consequently, this study determined that educational efficiency could be raised by providing historically more progressive views to cope with conflictory student thoughts-thoughts related to past views in science history.

• Journal of Information Processing Systems
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• v.14 no.1
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• pp.79-100
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• 2018

Twitter is one of the most popular social platforms for online users to share trendy information and views on any event. Twitter reports an event faster than any other medium and contains enormous information and views regarding an event. Consequently, Twitter topic summarization is one of the most convenient ways to get instant gist of any event. However, the information shared on Twitter is often full of nonstandard abbreviations, acronyms, out of vocabulary (OOV) words and with grammatical mistakes which create challenges to find reliable and useful information related to any event. Undoubtedly, Twitter event summarization is a challenging task where traditional text summarization methods do not work well. In last decade, various research works introduced different approaches for automatic Twitter topic summarization. The main aim of this survey work is to make a broad overview of promising summarization approaches on a Twitter topic. We also focus on automatic evaluation of summarization techniques by surveying recent evaluation methodologies. At the end of the survey, we emphasize on both current and future research challenges in this domain through a level of depth analysis of the most recent summarization approaches.

• Ocean and Polar Research
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• v.28 no.3
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• pp.259-272
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• 2006

The 1982 UNCLOS provided very detailed provisions on marine scientific research and gave coastal stale jurisdiction to regulate marine scientific research in its EEZ. However, due to lack of definition and criteria of MSR, there are some different views, even conflicts, regarding legal Pounds for governing hydrographic surveys and oceanographic data collection by one state in the EEZs of other states. Some coastal states argue that those activities should only be conducted in the EEZ of other states with the consent of the coastal state while it is the opinion of other states, including the U.S.A., that those activities can be conducted freely in the EEZ. This paper reviews different views and recent developments on the issue and suggests some recommendations for future work of the Korean government related to the activities.