• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.1
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• pp.133-151
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• 2019

In order to achieve faster content distribution speed and stronger fault tolerance, a P2P peer can connect to multiple peers in parallel and receive chunks of the data simultaneously. A critical issue in this environment is selecting a set of nodes participating in swarming sessions. Previous related researches only focus on performance metrics, such as downloading time or the round-trip time, but in this paper, we consider a new performance metric which is closely related to the network and propose a peer selection algorithm that produces the set of peers generating optimal worst link stress. We prove that the optimal algorithm is practicable and has the advantages with the experiments on PlanetLab. The algorithm optimizes the congestion level of the bottleneck link. It means the algorithm can maximize the affordable throughput. Second, the network load is well balanced. A balanced network improves the utilization of resources and leads to the fast content distribution. We also notice that if every client follows our algorithm in selecting peers, the probability is high that all sessions could benefit. We expect that the algorithm in this paper can be used complementary to existing methods to derive new and valuable insights in peer-to-peer networking.

• Tribology and Lubricants
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• v.33 no.6
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• pp.263-268
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• 2017

The significance of maintaining the soil environment is gradually increasing owing to soil and underground water contamination by petroleum leak accidents. However, the purification of soil is an expensive and more time-consuming process than the purification of contaminated water and air. Moreover, determining the source and people responsible for soil pollution gets often embroiled in legal conflicts, further delaying the cleanup process of the contaminate site. Generally, TPH (total petroleum hydrocarbon) pattern analysis is used to determine the petroleum species and polluter responsible for soil contamination. However, this process has limited application for petroleum products with a similar TPH pattern. In this study, we analyze the TPH pattern and specific sectional ratio (${\sim}C_{10}$, $C_{10}-C_{12}$, $C_{12}-C_{36}$, and $C_{36}{\sim}$) of various domestic petroleum products to identify the petroleum product responsible for soil contamination. Also, we perform BTEX (benzene, toluene, ethyl benzene, xylene) quantitative analysis and determine B:T:E:X ratio using GC-MS. The results show that gasoline grade 1 and 2 have a similar TPH pattern but different BTEX values and ratios. This means that BTEX analysis can be used as a new method to purify soil pollution. This complementary TPH and BTEX method proposed in this study can be used to identify the petroleum species and polluters present in the contaminated soil.

• Journal of Distribution Science
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• v.15 no.8
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• pp.29-36
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• 2017

Purpose - This paper proposes some ideas with a view to reducing any possible accidents caused by unlicensed drivers and an illegal use of other's name, particularly by teenagers in consideration of easy and simple instruction on smartphone with very weak and mere consciousness on auto life. Research design, data, and methodology - This study analyzes some accident cases between cargo trucks and rental cars in South Korea, and unlicensed vehicle with unlicensed drivers who use rental cars collided with cargo trucks which were loaded a lot of goods to be delivered to buyer designated. In order to fulfill this research, a case study accompanied with literature survey was conducted. Ideal suggestion for the right growth on rental car industry will be realized by legislation of the law. Results - This paper classified bodily injury of the victim, property damage and damaged cargo arising out of the unlicensed who is driving on car sharing service in South Korea. Conclusions - For the purpose of reducing cargo accidents caused by unlicensed drivers and an illegal use of other's name particularly by teenagers, this paper proposes some ideas of Amendment of the law, Paradigm shift of car sharing company, Preparation by association side and Technical Complementary Measures in South Korea.

• Structural Engineering and Mechanics
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• v.53 no.5
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• pp.867-880
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• 2015

Mechanical fastening is still one of the main methods used for joining components. Different techniques have been applied to reduce the effect of stress concentration of notches like fastener holes. In this work we evaluate the feasibility of combining laser shock peening (LSP) and cold expansion to improve fatigue crack initiation and propagation of open hole specimens made of 6061-T6 aluminum alloy. LSP is a new and competitive technique for strengthening metals, and like cold expansion, induces a compressive residual stress field that improves fatigue, wear and corrosion resistance. For LSP treatment, a Q-switched Nd:YAG laser with infrared radiation was used. Residual stress distribution as a function of depth was determined by the contour method. Compact tension specimens with a hole at the notch tip were subjected to LSP process and cold expansion and then tested under cyclic loading with R=0.1 generating fatigue cracks on the hole surface. Fatigue crack initiation and growth is analyzed and associated with the residual stress distribution generated by both treatments. It is observed that both methods are complementary; cold expansion increases fatigue crack initiation life, while LSP reduces fatigue crack growth rate.

• Journal of Distribution Science
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• v.15 no.2
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• pp.21-26
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• 2017

Purpose - Sharing economy is a promising research topic as a complementary approach for solving difficult issues resulting from market economy. Motive factors for consumer participation in sharing economy are necessary to facilitate the growth of sharing economy. This study analyzes motives for participating in sharing economy using samples from a car sharing service in South Korea. Research design, data, and methodology - Four hypotheses drawn from a new research model integrating the relationships between economic and social value, social value, and the intention to use sharing economy services were proposed. 292 valid samples were collected from Socar users in South Korea. Multiple regression analysis was employed to test the hypotheses. Results - An empirical study identified the importance of convenience and time savings as determinants of intention to use continuously a car sharing service. Cost savings and social value did not significantly influence the intention to use car sharing service. Conclusions - The present study implies that managers working in sharing economy don't have to miss a role of convenience. Although a new finding implies that convenience is an important factor influencing car sharing service, the present study has a limitation of generality that samples are mostly collected from the age range of 20 to 30 years.

• Journal of Korean Medicine for Obesity Research
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• v.9 no.1
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• pp.37-44
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• 2009

The study was to investigate the distribution for the diagnosis of pattern identification questionnaire and agreement rate between diagnosis of pattern identification based on obesity pattern identification questionnaire and the clinical diagnosis of pattern' identification by medical specialist. The distribution for the diagnosis of pattern identification based on obesity pattern identification questionnaire was shown in order of stagnation of liver Gi, retention of undigested food, deficiency of Yang at scale of 5, 3, 2 score and the diagnosis rate of single pattern identification at scale of 5, 3, 2 score was 89.96%, 79.33%, 54.64%, respectively the agreement rate between the diagnosis of pattern identification based on obesity pattern identification questionnaire and the clinical diagnosis of pattern identification by medical specialist was 0.1013. Therefore, the complementary management in CRF questionnaires with consultation from experts and the study for score difference of pattern identification will improve the accuracy and agreement rate, which will will be helpful for pattern identification of obesity by clinical experts.

• Nuclear Engineering and Technology
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• v.52 no.8
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• pp.1714-1723
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• 2020

This study aims at characterizing the rheological properties of uranium oxide powders for nuclear fuel pellets manufacturing. The flowability of these powders must be compatible with a reproducible filling of press molds. The particle size distribution is known to have an impact on the rheological properties and fine particles (<100 ㎛) are suspected to have a detrimental effect. In this study, the impact of the particle size distribution on the rheological properties of UO₂ powders was quantified, focusing on the influence of fine particles. Two complementary approaches were used. The first approach involved characterizing the powder in a static state: density, compressibility and shear test measurements were used to understand the behavior of the powder when it is transitioned from a static to a dynamic state (i.e., incipient flow conditions). The second approach involved characterizing the behavior of the powder in a dynamic state. Two zones, corresponding to two characteristic behaviors, were demonstrated for both types of measurements. The obtained results showed the amount of fines should be kept below 10 % wt to ensure a robust mold filling operation (i.e., constant mass and production rate).

• Journal of Distribution Science
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• v.18 no.10
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• pp.15-23
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• 2020

Purpose: Crowdfunding can be a complementary channel in which start-ups or small companies can obtain financial help and take advantage of exploiting the online potential. To activate crowdfunding, it is necessary to consider a consumer's empathic responses. This article examines the role of empathy in the crowdfunding channel platform. We adopted the identification-commitment model to prove the role of empathy. Research design, data, and methodology: Participants were asked to read the charitable crowdfunding campaign. More than 300 young adults completed an online questionnaire and we analyzed it with structural equation modeling (SEM). To find out the role of empathy, we postulate several models which use empathy variable for different purposes. Results: We conclude that empathy has the role of moderator in the identification-commitment model. This means the high empathic response helped the relationship between identification and commitment. However, low empathic response can negatively influence the process of identification to commitment. Conclusions: This study found that virtual empathy is positively related to crowdfunding participation if we can elevate empathy in the crowdfunding channel platform. The findings also show that we need to consider empathic response when we want to raise funds for specific projects such as protecting the natural environment.

• Journal of Distribution Science
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• v.14 no.3
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• pp.23-30
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• 2016

Purpose - This research focuses on the analysis of logistics barriers in Korea, China and Japan facing the barriers of overseas-expanded manufacturers with other countries. With the tree countries are emerging as the biggest trade partners in Northeast Asia, their logistics barriers are applied with similar verification methods of preceding researches such as Carter(1997). Research design, data and methodology - Collecting the statistics data from the three countries' overseas-expanded manufacturers, t-verification was performed in order to analyze average value and verify any significance. Additionally, multiple regression analysis was used to analyze any influence on the relationship in Korean logistics barrier and Chinese and Japanese expansion to Korean market. Results - Statistics suggested that three countries' logistics barriers are significantly differentiated by each verification categories, and Korean barrier negatively affected Chinese and Japanese manufacturers coming into Korean market. Conclusions - As a result of multiple regression analysis of the influencing relationship between Korea's logistics barrier and Chinese and Japanese companies coming into Korean market, all of the Korean barriers are affecting the companies as an obstructive factor, and it is proved to be statistically meaningful. Therefore, in order to reduce Chinese and Japanese companies' cost burden, it is necessary that not only reasonable charge system and taxation support but also comprehensive measure establishment reduce Korea's logistics barriers. However, since this research has a limitation in samples and shows a period of 5 years in the three nations' trade barriers, continuous and complementary researches are necessary in order to develop certain objectivity.

• The Korean Journal of Zoology
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• v.37 no.3
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• pp.304-310
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• 1994

Using in situ hybridization, we have mapped the anatomical localization of perikarya containing myNA that codes for sonadotropin releasing hormone (GnRH) in the brains of female frogs, R. dybowskii. DNA olisomers, with sequences complementary to the GnRH portion of pro-GnRH myNA sequence, were synthesized and hybridized to paraformaldehvde-fixed, sagittal sections of the whole brain stem. The distribution of the GnRH mRNA containing cell bodies was similar to that described for GnRH peptide by immunohistochemistrv. That is, cells containing GnRH mRNA were observed in the medial septal area, anterior preoptic area, ventromedial hvpothalamus and infundibular regions. However, another cell groups which contains GnRH mRNAs were also detected by in situ hybridization in the bed nucleus of hippocampal commissure, preoptic area, nucleus infundibularis dorsalis, mesencephalic nuclei and intermediolateral cell column of spinal cord areas. These results demonstrate the feasibility of using in situ hybridization as a strategy to study the distribution of GnRH neurons and the detection of GnRH gene expression in the vertebrates.