• Journal of the korean academy of Pediatric Dentistry
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• 제39권4호
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• pp.339-347
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• 2012

There still remains a controversial debate whether facial skeletal morphological differences exist between patients with nasal and mouth breathing habits. The aim of this study is to assess a relationship between over a period of time mouth breathing and facial skeletal morphology by analyzing lateral cephalometric radiographs of patients with nasal or mouth breathing habits. A total of 120 patients with skeletal class I, II, and III, who had undergone orthodontic diagnosis in department of pediatric dentistry - chonbuk national university, were chosen and their lateral cephalometric radiographs were analyzed. These patients were divided into six groups of 20, each with or without mouth breathing habits. The result of this study has not showed noticeable differences in cephalometric measurements between nasal and mouth breathing children of skeletal class I, II, and III (p > 0.05). However, when the groups were divided by age factor, mouth breathers of age 12 and older showed significant differences in cephalometrics such as decreased ramus height, maxillary retrusion, and clockwise pattern of mandible than children under age 12 (p < 0.05). In conclusion, a longer period of mouth-breathing habits in children displayed a greater chance of impaired facial growth.

• The korean journal of orthodontics
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• 제39권5호
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• pp.330-336
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• 2009

Objective: To examine the differences in lateral cephalometric characteristics between patients with dental protrusion and crowding in order to determine what factors affect dental protrusion or crowding while both malocclusion types are caused by large tooth size. Methods: Twenty nine individuals with dental protrusion and 22 individuals with dental crowding were enrolled in this study. All subjects had larger teeth than average and Class I molar relationships. Craniofacial characteristics and hyoid bone positions were determined from lateral cephalograms and compared between the two groups. Results: In the comparisons of craniofacial characteristics, the measurements indicating maxillary length and facial convexity showed greater values in the protrusion group than in the crowding group. Comparisons of hyoid bone positions showed that the hyoid bone was positioned more anteriorly and superiorly in the protrusion group than in the crowding group. Conclusions: The results of the present study indicate that some craniofacial characteristics and tongue position may affect the development of dental protrusion or crowding; when an individual has large teeth, dental protrusion or crowding might be determined according to maxillary growth and tongue position.

• Journal of Korea Technology Innovation Society
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• 제20권2호
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• pp.487-517
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• 2017

In the context of an increased demand in universities' expansion of networks between other innovation actors, this research attempts to make a comparison on university-centered SCIE knowledge networks between regions. Using regional comparison, we have looked into these networks in regards to their characteristics, the importance of regional boundaries, and the effect of the regional industrial policy. As a result of this comparative analysis, we discovered that the point universities and research universities hold high centrality in regional knowledge networks, and that the characteristics of regions are reflected into this network. For instance, the Gyeonggi province had a preeminent level of industry-academy relationship, while for Daejeon it was public research institutions and academy, and Gangwon province it was between academy between academy. As a network analysis based on journals above SCIE levels, regional boundaries were not very clear in the network structures. However, within these boundaries, the impact of regional industrial policies were proven to be stronger in the Gang-won province where the academy-academy network was most prominent. The implication of this research outcome is that for regional innovation, government should more actively implement policies that can link academic institutes' knowledge to industry by expanding knowledge networks. In addition, we emphasize on the necessity of a regionally-appropriate policy, rather than a generalized industrial policy. And fundamentally, in regards to innovation, establishing a sound industrial infrastructure for regional development and efforts to link relevant actors are required.

• Journal of The Korean Society of Grassland and Forage Science
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• 제7권3호
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• pp.128-134
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• 1987

This experiment was conducted to evaluate the effects of cutting in field and solution culture. Periodical samplings of alfalfa in cutting and uncutting plots were taken to measure nodule development and nodule activity. Regrowth of plant and nodule development after shoot cutting by different heights and nodule removal at different levels were investigated in solution culture of alfalfa plant. 1. Nodule weight in the field was reduced 30% after the first cutting and 25% after the second cutting, but during the following 30 days after second cutting, there was no significant difference between cutting and uncutting plots. 2. Specific nodule activities of cutting plots at the beginning of June and at the beginning of September were 80% and loo%, higher than those of uncutting plots respectively. Total nodule activities of cutting plots in late August and early September were 40% higher than those of uncutting plot. The decrease of nodule activity can be prevented by cutting at flowering stage. 3. The decrease of nodules in solution culture when 50% of the shoot was cut, was as much as that when shoot was not cut or flower buds were removered. But when 90% of the shoot was cut, the number of the nodules were decreased more remarkably than the above treatments. New nodules, when 90% of the shoot was cut, were reformed slowly and did not grow fully until 15 days after cutting.

• Journal of Gifted/Talented Education
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• 제22권3호
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• pp.757-777
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• 2012

Peer relationships in young students' communities are one of the important factors influencing the cognitive and affective domains of learning. Moreover, students who join the special program for gifted students possess differential peer relationships from the students in general classes. This study aims to explore the differences of 5th grade five science-gifted students' peer relationships between students in special classes for gifted students and general classes. Five students in the special program for gifted students, managed by the Office of Education in a southern city, participated in this study. Social network analyses were utilized to explore participants' peer relationships; the students' homeroom teacher was interviewed to explore the contextual and in-depth characteristics of gifted students' peer relationships. The results illustrated four cases of peer relationships: (1) smart loner (2) my study mate (3) I'm the best in my class, and (4) a good friend anywhere. This study identified that the gifted students possessed diverse peer relationships in both the special program and general classroom. In addition, this study suggests that the program for gifted students needs to be specially designed based on the gifted students' peer relationship.

• The Journal of Society for e-Business Studies
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• 제21권3호
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• pp.29-50
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• 2016

We explore the impact of individuals'network position toward knowledge sharing intention. In order to identify network positions, we utilize three centrality measures (degree/closeness/betweenness) of individual network participants. The research findings show that the individual network positions significantly affect knowledge sharing intentions. Since an individual with high degree centrality might be the leader or the hub, one makes considerable effort to maintain the network position by actively participating in intra-team and inter-team knowledge sharing, A participant who can quickly interact with many other participants within a team (high closeness centrality) is more interested in intra-team knowledge sharing than inter-team knowledge sharing. Unlike degree centrality and closeness centrality, the betweenness centrality provides a participant with diverse resources located in multiple sub-groups. Although an individual with high betweenness centrality is not at the center of the networks, one plays a crucial role in disseminating and regulating information. Therefore, the individual is likely to have more positive intention toward inter-team knowledge sharing than intra-team knowledge sharing.

• The Journal of the Korea Contents Association
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• 제14권9호
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• pp.437-449
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• 2014

In order to suggest alternative directions for the regional development of Chungcheongbukdo through social network analysis (SNA) methods, this study highlights networking features of Chungcheongbukdo-based top 300 enterprises. In particular, it has paid attention to network relationships among participating enterprises and their basic structure, all of which play pivotal roles in provincial development. Major networking features among Chungcheongbukdo-based top 300 enterprises are dichotomized between structural and positional dimensions. Firstly, in terms of structural approach, this research confirms that both relational density indices and average connectivity levels among key enterprises have been extremely low. Therefore, the exchange networks seem relatively limited. That is, two enterprises could be interconnected after 1.1 stages in average, implying that the most popular types come from direct relationship among participating enterprises. In addition, this research finds that 7 major networks hinged upon 'distributed centralization types' present active information exchange, taking in charge of brokerage roles, all of which have contributed to broader network formation. Nonetheless, as the weight of minor network outweighs that of major network, more active supporting measures should be designed.

• Management & Information Systems Review
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• 제35권2호
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• pp.221-254
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• 2016

With increasing interest of health due to population aging, medical device industry is highlighted as a promising industry. However, Korea medical device industry is not enough market competitiveness compared to global company due to a narrow domestic market and a small company structure. In order to retain the national competitiveness, it is necessary that we have to derive a central technology and its trend. This study has predicted a central technology for medical device industrial using patent network analysis. The central technology is defined as a key technology that is connected to most other technologies and that significantly affects them. For the empirical study, we conducted social network analysis using covariance and correlation coefficient between IPC codes extracted from medical device patents, introduced by Jun(2012). A social network is a social structure of diverse items as well as of human beings. In this study, we set each medical device as a node in an SNA and analyze the Degree values between them. Also, Korea health industrial statistics system are utilized for verification of selected central technology. As a result, we found that the central technology is located on the medical device items, which are listed higher the amount of production. The central technology selected through the proposed methodology will provide a inspiration for establishment of R&D policy.

• The Journal of the Korea Contents Association
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• 제19권10호
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• pp.685-697
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• 2019

The study aimed to analyze the structure of China's passenger railway network in the years of 2008, 2013, and 2018, respectively. At the same time, it tried to investigate its derivative impact on the patterns of Chinese urban network. The analytical tool was based on the NetMiner4.0. In order to measure network characteristics of China's passenger railway network, it primarily focused on the degree centrality, betweenness centrality, and closeness centrality. First of all, the higher degree centralities, with a few exceptions, were observed in BeiJing, ShangHai, GuangZhou, WuHan, XiAn, ChengDu, HaErBin, and ShenYang over a decade. In contrast, the higher betweenness centralities were recorded in cities of higher development potential including WuLuMuQi, GuiYang, ShenYang, and KunMing. The closeness centrality analyses confirmed the fact that most metropoles like BeiJing, ShangHai, and GuangZhou kept the highest train accessibility during the same research period. At the same time, the opening up of a new stretch of high speed railway network has consecutively strengthened connectivity between BeiJing and TianJin. Owing to unprecedented development of railway traffic and its extensive operations, this study believes that Chinese major cities, without interruption, would pursue a series of urban policy alternatives geared towards railway stations-oriented networking and competitively try to extend their network ranges.

• Korean Journal of Construction Engineering and Management
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• 제20권6호
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• pp.107-116
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• 2019

Korean construction engineering firms want to pave the way for expansion of overseas markets through the World Bank's Official Development Assistance (ODA) projects as a way to improve their overseas project performance. However, since the World Bank project competes with global companies for limited projects, building partnerships with suitable business partners is essential to gain an upper hand in bidding competition and meet the institutional conditions of the recipient country. In this regard, many network studies have been conducted in the past through Social Network Analysis (SNA), but few have been analyzed based on the process of changes in the network. So, This study collected winning data from the three Southeast Asian countries that ended after the World Bank's ODA project performed smoothly, and established a learning-based link prediction model that reflected the dynamic nature of the network. As a result, the 11 main variables acting on building a cooperative relationship between winning companies were derived and the effect of each variables on the probability value of cooperation between individual links was identified.