• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.6C
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• pp.614-622
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• 2006

In this paper, we propose an efficient packetization method to reduce the packetization overhead. For the purpose, we firstly verify the relationship between packet length and packet loss rate. The empirical results show that as the packet length is larger than the path MTU, the packet loss rate is drastically increased, producing poor visual quality at the receiver side. However, as the length of the packet is reduced, we should transmit more packets per frame and the packetization overhead will be increased. This increase in the packetization overhead reduces the number of bits allocated to the video data, resulting in the low visual quality. Therefore, each packet should be packetized to have the packet length close to the path MTU. In this paper, we show that the this process of the packetization with the constraint on the packet length is very similar to the dynamic storage allocation in the operating system. We had thoroughly surveyed the dynamic storage allocation methods used in the recent operating systems and propose to use the allocation methods for the video packetization. We empirically show that the proposed method can reduce the packetization overhead upto 28.3%, compared with the conventional sequential packetization method which have been widely used in Internet video transmission.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.43 no.3
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• pp.167-178
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• 2020

The purpose of this study is to examine the relationship between internal corporate, supplier, and customer integrations for domestic SMEs on non-financial and financial performance through SCM performance such as flexibility and reduction of uncertainties. To this end, data was collected on 286 SMEs in Korea, and the structural relationships between SCM integration level, SCM performances, and management performance were analyzed. As a result of the analysis, first, it was found that the SCM integration level had a significant positive effect on the flexibility and reduction of uncertainties, which are SCM performances. Second, the flexibility and reduction of uncertainties showed significantly positive effects on the non-financial performance of the companies, but did not directly affect the financial performance positively. Third, the non-financial performance was found to have a positive effect on the financial performance. In addition, the SCM integration level did not have a direct effect on the financial and non-financial performance, but it was found that it affected management performance by mediating the flexibility and reduction of uncertainties, which are SCM performances. That is, although the SCM integration level did not directly affect financial and non-financial performance, it was confirmed that it affects management performance by mediating SCM performances, flexibility and uncertainty reduction. In other words, it was confirmed that the SCM integration level directly or indirectly affects SCM performances and overall management performance. These results imply the necessity to focus on competency in the supply chain management area according to the SCM performance expected by SMEs, and the step by step approaches to the expected effects. In a situation where prior SCM related studies have not been able to present SCM performances and management performance of SMEs that are relatively lacking in their capital and SCM construction capabilities, the findings of this study could suggest the importance of SCM integration from the perspective of SMEs. In addition, from the viewpoint of SMEs, this study suggested that a sequential approach for performance measurement is required (SCM performance → management performance) in relation to the performance factors to be established through SCM.

• Korean journal of applied entomology
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• v.40 no.3
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• pp.197-202
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• 2001

The density of citrus red mite(CRM), Panonychus citri(McGregor), on the commercial satsuma mandarin Citrus unshiu L. groves were determined by counts of the number of CRM per leaf using by leaf sample in Jeju for 2 years. Binomial sampling plans were developed based on the relationship between the mean density per leaf(m) and the proportion of leaf infested with less than T mites per leaf($P_{T}$), according to the empirical model $ln(m)={\alpha}+{\beta}ln(-ln(1-P_{T}))$. T was defined as tally threshold, and set to 1, 3, 5 and 7 mites per leaf in this study. Increasing sample size, regardless of tally threshold, had little effects on the precision of the binomial sampling plan. Increasing sampling size had little effect on the precision of the estimated mean regardless of tally thresholds. T=1 was chosen as the best tally threshold for estimating densities of CRM based on the precision of the model. The binomial model with T=1 provided reliable predictions of mean densities of CRM observed on the commercial satsuma mandarin groves. Binomial sequential sampling procedure were developed for classifying the density of CRM. A binomial sampling program for decision-making CRM population level based on action threshold of 2 mites per leaf was obtained.

• Research in Plant Disease
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• v.24 no.3
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• pp.213-220
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• 2018

We classified the previously reported antagonistic strains of Sorangium cellulosum into 5 subspecies (A-E). Four strains were antagonistic to Botrytis cinerea (AB group) and two strains were antagonistic to Colletotrichum acutatum (AC group). According to the genetic and sequential analyses with standard genes, xynB1, bglA2, groEL1 for grouping, all strains of AB group were belonged to subspecies C and all strains of AC group were belonged to subspecies D. In addition, high pressure liquid chromatography with the culture filtrates confirmed the genetic results, because AB group had peaks with retention time at 20-22.5 minutes, whereas AC group had no peak. There was positive relationship ($R^2=0.9652$) between the control values of infecting B. cinerea on cherry tomatoes and the main peak areas of chromatograms among the four isolates of AB group. From the subspecies results of AB group, the main peak of KYC 3270 was expected to be epothilone D. However the retention times of the standard of commercial epothilone D and the main peak of KYC 3270 culture filtrate were different as 9.9 and 11.581 min., respectively. Finally, the antagonistic metabolite of AB group was inferred as 7-ketone epothilone D.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.24 no.1
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• pp.41-46
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• 2013

Background & Objectives : The Speech Handicap Index (SHI) is used to assess speech problem of head and neck cancer patients. The aim of this preliminary study was to evaluate the reliability and validity the Korean version SHI. Materials and Methods : Sixteen patients with oral cavity cancer and 26 normal control were participated in the study. Test-retest reliability of the Korean version of SHI was completed by 20 out of 42 subjects after 2weeks. Mann-Whitney U test was used to compare the Korean version of SHI scores between normal population and patients group. The relationship between the Korean version of SHI and diadochokinesis (DDK) was investigated using Spearman correlation coefficients. Results : The Korean version of SHI provided a high internal consistency (${\alpha}$=0.99) and test-retest reliability (Spearman rho 0.98). The mean SHI scores [total (T), speech (S), and psychosocial (P)] in normal population were 0.8 (T), 0.2 (S) and 0.4 (P), whereas those in patients group were 58.1 (T), 27.9 (S) and 27.0 (P) respectively. There were significant differences in total SHI score as well as in all of the sub-SHI scores between two groups. Moreover, significant correlation between the Korean version of SHI parameters (T, S, P) and sequential motion rate (SMR) were yielded in patients group. Conclusion : The Korean version of SHIwas reliable and valid. It can be useful as a supplementary clinical tool for diagnosing and measuring treatment efficacy of speech problems related to oral cavity cancer.

• (The) Research of the performance art and culture
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• no.35
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• pp.203-227
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• 2017

In this thesis, I examined the characteristics of modernism in this work, focusing on the melodrama "Sarang ye soggo donye wulgo(means 'Crying in Love and Crying for Money')", which was popular in the 30s when the consciousness of modernity was overflowing. There has never been an example of a connection between modernism and drama in the 1930s. The characteristic of modernism is clearly embedded in the representative drama of "Sarang ye soggo donye wulgo(means 'Crying in Love and Crying for Money')" at that time. In the title "Sarang ye soggo donye wulgo(means 'Crying in Love and Crying for Money')". 'Don' reveals modern elements. 'Love' can be seen as revealing melodramatic elements. The flair of modern art, which is a background to reveal modern elements, is spread throughout the works. Hongdo fails to complete the relationship with his family, as well as with the couple. It became a person who accepted the modernistic phenomenon by showing the domination of matter. While the typical method of constructing conflicts in the pre-modern narrative works is horizontal and sequential, it can be said that it was in the form of a train station, while the post-modern era of narrative conflict formation from the 30s forms a plurality of conflicts simultaneously, can do. The fear of the ordinary people who see the reality that urban and western values are already rampant by attempting new contents that lead the change of values in "Sarang ye soggo donye wulgo(means 'Crying in Love and Crying for Money')" became a factor to transfer into internal conflict again.

• (The)Korea Educational Review
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• v.24 no.1
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• pp.147-172
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• 2018

This study aims to seek lifelong educational implications and supports for middle aged women who experience empty nest period. Empty nest period has gained limited attention in research even though it is an important period through which middle aged women review and re-evaluate their past life and prepare for their next. This study tries to understand how they experience the empty nest period and how it affects their life, and suggest lifelong educational implications. A total number of 10 middle aged women were interviewed. They were selected by the reason that they either have experienced or are currently in the empty nest period. The collected samples were analyzed by constant comparative method based on grounded theory and were named & categorized through sequential process of open coding, axis coding and selective coding. While story-telling the experiential process of empty nest period, this study found 2 main criteria, will of change and actualization, based on which 4 different types of middle aged women's experience were withdrawn. Those 4 types are self-seeking, role-adaptive, relationship-focused and change-unwillingly and each type was explained with its own characteristics. Based on study result, lifelong educational implications for middle aged women were suggested.

• Communications of Mathematical Education
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• v.35 no.2
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• pp.153-172
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• 2021

Various competencies such as critical thinking, systems thinking, problem solving competence, communication skill, and data literacy are likely to be required in the 4th industrial revolution. The competency regarding data literacy is one of those competencies. To nurture citizens who will live in the future, it is timely to consider research on teacher education for supporting teachers' development of statistical thinking as well as statistical knowledge. Therefore, in this study we developed and implemented a data analysis project for pre-service teachers to understand their changes in statistical knowledge in addition to their experiences of data-driven decision making process that required them utilizing their statistical thinking. We used a mixed method (i.e., sequential explanatory design) research to analyze the quantitative and qualitative data collected. The findings indicated that pre-service teachers have low knowledge level of their understanding on the relationship between population means and sample means, and estimation of the population mean and its interpretation. When it comes to the data-driven decision making process, we found that the pre-service teachers' experiences varied even when they worked as a small group for the project. We end this paper by presenting implications of the study for the fields of teacher education and statistics education.

• Journal of Intelligence and Information Systems
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• v.28 no.1
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• pp.1-28
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• 2022

In recent years, many Internet giants have begun providing their own content services, which attract online users by offering personalized services based on artificial intelligence technologies. This study investigates the role of two firms' content services within the firms' online service network. We examine the role of Naver Webtoon, which can be characterized as a professional-generated content, within Naver's service portfolio, and that of Google YouTube, which can be characterized as a user-generated content, within Google's service portfolio. Using survey data on viewers' use of the two services, we analyze a valued directed service network, where a node denotes an online service and a relationship between two nodes denotes a sequential use of two services. We found that both Webtoon and YouTube show higher out-degree centrality than in-degree centrality, which implies these content services are more likely to be starting services rather than arriving services within the firms' interactive network. The gap between the out-degree and in-degree centrality of YouTube is much smaller than that of Webtoon. The high centrality of YouTube, a user-generated content service, within the Google service network shows that YouTube's initial role of providing specific-content videos (e.g., entertainment) has expanded into a general search service for users.

• Journal of Music and Human Behavior
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• v.20 no.2
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• pp.61-88
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• 2023

This case study examined whether a cooperative musical instrument playing could enhance interactions between children with autism spectrum disorder (ASD) and their neurotypical (NT) siblings. It involved three children with ASD aged 7-12 years and three NT siblings aged 6-11 years. Each group, comprising a child with ASD and their NT sibling, participated in a 40-minute sessions twice weekly for eight sessions over four weeks. The intervention included three stages: simultaneous action, complementary action, and achieving a joint goal. Evaluation criteria included the initiation and response behaviors of each child, and sequential interactive behaviors and cooperative behaviors between pairs were measured. Additionally, before and after the intervention, parents and NT sibling assessed their perceived sibling relationships. Results showed increased interactive and cooperative behaviors. Post-intervention, both parents and NT siblings rated the sibling relationship highly, despite little change in sibling conflict and competition consciousness. These findings indicate that interactive instrument playing can enhance perceptions of siblings as cooperative play partners and aid in teaching them how to collaborate during interactions.