• Korean Journal of Soil Science and Fertilizer
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• v.47 no.5
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• pp.351-355
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• 2014

In recent years, biochar has received much attention as soil amendment, enhancing soil fertility and reducing toxicity of heavy metals with its large specific surface area and high pH. Biochar has also the effect of alleviating global warming by carbon sequestration from recycling organic wastes by pyrolysis. However, scattering of fine particles of biochar is a hindrance to expand its use from human health point-of-view. Alginate, a natural polymer without toxicity, has been used for capsulation and hydrogel fabrication due to its cross-linking nature with calcium ion. In this study, the method of cross-linkage between alginate and calcium ion was employed for making dust-free biochar bead. Then an equilibrium adsorption experiment was performed for verifying the adsorption effect of biochar bead on heavy metals (cadmium, copper, lead, arsenic, and zinc). Results showed that biochar bead had effects on adsorbing heavy metals, especially lead, except arsenic.

• Journal of the Korean Data and Information Science Society
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• v.26 no.1
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• pp.209-216
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• 2015

Quantile regression models with covariate measurement errors have received a great deal of attention in both the theoretical and the applied statistical literature. A lot of effort has been devoted to develop effective estimation methods for such quantile regression models. In this paper we propose the partially linear support vector orthogonal quantile regression model in the presence of covariate measurement errors. We also provide a generalized approximate cross-validation method for choosing the hyperparameters and the ratios of the error variances which affect the performance of the proposed model. The proposed model is evaluated through simulations.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.10
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• pp.1269-1274
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• 2014

Due to the presence of Dean flow in curved ducts, helical channels have drawn attention recently because of the practical industrial applications. The manipulation of fluids through microfluidic devices is widely used in many scientific and industrial areas. In the present study, numerical simulations were performed on a helical microchannel to predict the impact of different design parameters that affect Dean flow. Important geometric parameters such as the channel cross section, pitch, radius of curvature, and number of turns were considered for the analysis. The study also incorporates the effect of varying flow rate on Dean flows. It was found from the simulation results that microchannel cross section and pitch have a significant impact on maintaining the Dean flow, compared to the radius of curvature, number of turns, and flow rate.

• Cross-Cultural Studies
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• v.29
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• pp.453-477
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• 2012

This study investigates how the truth-related words in Korean, which were originally noun or adverb with 'truth' related meaning, can be used as discourse markers with the functions such as 'emphatic marker', 'attention getter', or 'hesitation marker', and it argues that such functions of the discourse markers are the result of grammaticalization process. That is to say that the truth-related words have acquired new functions as discourse markers from their corresponding lexical items as a noun or an adverb through grammaticalization process. In this study, we demonstrate that the truth-related words tend to appear sentence-initially or sentence-medially when they are used as discourse markers. We also show that they are most likely to be used as emphatic marker because of the lexical meaning of the truth-related words. Finally, we state that truth-related words differ from one another in where they appear and what function they are used with.

• Cross-Cultural Studies
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• v.38
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• pp.331-349
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• 2015

"San-Jia-Zhu" is the integrated study of "Shi-Ji" of the Sui and Tang dynasty. It has preserved the ancient note large, rich notes, annotation methods, which have a greater impact on historical research. In collating, "San-Jia-Zhu" not only for 's error correction, and the comprehensive use of various methods of collation in collating process. First, he paid attention to the contrast between different versions very much, to determine the word errors using the similarities and differences between different versions of the diffracted off. This draft is $\ll$Shiji${\gg}$ from ancient Chinese research methods to explore the characters, phonology, syntax, exegesis, collation of historical value.

• Asia Marketing Journal
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• v.15 no.2
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• pp.1-27
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• 2013

The main goal of this study is to examine the competition intensity in the Korean bakery franchise industry and to identify the core competencies of the industry's leading company, Paris Baguette. The frameworks of PEST analysis, Cross Impact analysis, a Five Forces Model, a Value Chain, and VRIO analysis. PEST and Cross Impact analysis were employed to investigate the industry's external environment, and the results indicated that 'increased attention on corporate's Creating Shared Value (CSV) activities' is the most influential factor among others. The analysis using the Five Forces Model found industry rivalry and substitutes were the greatest threats. Finally, the results of Value Chain and VRIO analysis identified four core competencies of Paris Baguette: its CEO's craftsmanship, e-procurement system, quality of dormant dough, and hub system. Multiple managerial implications are suggested for practitioners in the marketing area, especially in the saturated market environment.

• Annals of Occupational and Environmental Medicine
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• v.35
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• pp.31.1-31.10
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• 2023

Background: With modernization, air pollution has become increasingly serious, and its effects on health have been revealed. As a result, public interest in environmental pollution has become critical for regulating air pollution. In our study, we aim to evaluate the impact of air pollution levels on public attention to environmental issues and examine whether awareness of the residential environment's impact on health acts as a mediator in this relationship. Methods: We conducted an analysis on 400 individuals surveyed in the preliminary feasibility study on adverse health effects in the Pohang Industrial Complex, to examine the relationship between particulate matter 2.5 (PM2.5) and attention to environmental issues. Logistic regression analysis was performed, and mediation analysis was used to determine whether awareness of the residential environment's impact on health mediated the relationship. Results: The logistic regression analysis results showed that PM2.5 levels were associated with attention to environmental issues (adjusted odds ratio [AOR]: 2.1; 95% confidence interval [CI]: 1.3-3.5; p = 0.003) and awareness of health impacts (AOR: 3.4; 95% CI: 1.6-7.1; p = 0.001). The PM2.5 levels showed 9.9% (95% CI: 5.4-14.0) increase in the prevalence of high attention to environmental issues, of which, only 1.0% (95% CI: 0.2-2.3) were mediated by health impact awareness. In the overall analysis, 10% of the total effect of PM2.5 on attention to environmental issues was mediated by health impact awareness. Conclusions: According to this study's results, there was a correlation between air pollution levels and attention to environmental issues. Awareness of the health impacts of air pollution partially mediated the effect of air pollution levels on attention to environmental issues. In future studies, it is recommended to identify other mediators to further understand this structure.

• Journal of Advanced Marine Engineering and Technology
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• v.34 no.5
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• pp.703-710
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• 2010

Recently, small hydropower attracts attention because of its clean, renewable and abundant energy resources to develop. However, suitable turbine type is not determined yet in the range of small hydropower and it is necessary to study for the effective turbine type. Therefore, a 80kW-Class cross-flow turbine is adopted in this study because of its simple structure and high possibility of applying to small hydropower. The result shows that as effective head increases, tangential and radial flow velocities increase and thus, the increased tangential velocity contributes to the increase of angular momentum and output torque.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.12A
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• pp.1189-1197
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• 2006

Ultra-wideband(UWB) is a killer technology for short-range wireless communications. In the past, most of the UWB research focused on physical layer but the unique characteristics of UWB make it different to design the upper layer protocols than conventional narrow band systems. Cross-layer protocols have received high attention for UWB networks. In this paper, we investigate the performance of two physical layer schemes: Time Hopping Binary Pulse Position Modulation(TH-BPPM) and Time Hopping Binary Pulse Amplitude Modulation (TH-BPAM) with proposed private MAC protocol for UWB ad-hoc networks. From pulse level to packet level simulation is done in network simulator ns-2 with realistic network environments for varying traffic load, mobility and network density. Our simulation result shows TH-BPAM outperforms TH-BPPM in high traffic load, mobility and dense network cases but in a low traffic load case identical performance is achieved.

• Korean Journal of Artificial Intelligence
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• v.7 no.2
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• pp.9-12
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• 2019

With the Chinese government's attention to the artificial intelligence industry, the Chinese government has invested a lot in it recently. Of course, the importance of artificial intelligence industry for China's economic development is increasingly significant. The advent of artificial intelligence boom has also triggered a large number of scientists to analyze the impact of artificial intelligence on economic growth. Therefore, this paper use 31 China's cross-province panel data to study the effect of artificial intelligence on economic growth. Via empirical analyses under a series of econometric methods such as the province and year fixed effect model, the empirical result shows that artificial intelligence has a positive and significant effect on economic growth. Namely, the artificial intelligence is a new engine for economic growth. Meanwhile, the empirical results also indicate that the investment and consumption has a significant and positive effect on economic growth. Oppositely, the inflation and government purchase have a significant negative effect on economic growth. These findings in this paper also provide some important evidences for policy-makers to perform precise behaviors so as to promote the economic growth. Moreover, these finding enriches existing literature on artificial intelligence and economic growth.