• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.05a
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• pp.250-253
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• 2010

Underwater sensor network has attracted more and more attention from the networking research community recently. Most of traditional studies focus on the topology with a single gateway. Underwater sensor network consists of a variable number of sensors and multi-gateway to ensure the reliability of the network. In this paper, we propose a new MAC protocol that can reduce collisions among sensor nodes and improve QoS(Quality of Service) for underwater sensor network with multi-gateway. We evaluate the performance of the proposed scheme through simulation. Simulation results show that the proposed scheme outperforms the existing MAC protocol.

• Nuclear Engineering and Technology
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• v.50 no.5
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• pp.767-772
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• 2018

Public acceptance is a major issue that will determine the future of nuclear energy. In this article, we review relevant studies and identify several common patterns of nuclear public acceptance. Based on these patterns and four categories of factors, we propose hypotheses on the impact of different socioeconomic factors on the public opinion of nuclear energy. These factors were demographic and social influences, politico-economic, energy conditions, and nuclear accidents and natural risks. We tested these hypotheses using a data set including survey results on public opinion of nuclear energy in 59 countries from 1987 to 2014. Results of the regression analysis generally verified the proposed hypotheses, especially regarding the positive impact of education or geological suitability and the negative effect of improved living standards and democracy on nuclear acceptance. We propose policy recommendations, including a better focus on education and communication and a thorough consideration of the social and geological conditions a country needs to make before deciding to go nuclear. Potential weaknesses of this study are also discussed, including the possible causal relation between independent variables and the binary nature of the dependent variable.

• The Journal of Internal Korean Medicine
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• v.18 no.2
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• pp.40-52
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• 1997

1. Xiaoke(消渴) had been defined symptoms as polyuria with polydysia in Han and Dang Dynasty(漢唐時代), diagnosed variable disease as to the region of typical symptoms in Jin and Yuan Dynasty(金元時代) and classified into Upper-jiao(上消), Middle-jiao(中消), Lower-jiao(下消) by typical symptoms in Ming and Qing Dynasty(明淸時代). 2. The complications of Xiaoke(消渴) consist of carbuncle and phlegmon(癰疽), hemorrhoid and diarrhea(痔疾), an eye disease(眼病) such as nyctalopia(雀目) and cataract(內障) without Zhongman and Guzhang(中滿鼓脹) resulted from wrong medical treatmentis considered the pathology of Huore(火熱) 3. The pathology of Xiaoke(消渴) has been taken an instance of Shen-zao(腎燥), Five zang-organs's ganzao(五臟乾燥), Zao-re(燥熱), Shi-huo(實火) and Xu-huo(虛火), and since Jin and Yuan Dynasty(金元時代) generally cosidered Zao-re(燥熱). 4 The complications of Xiaoke(消渴) are explained the pathology of Huore(火熱), in the an opinion that the the pathology of Huore(火熱) changed into Zao-re(燥熱), and then Zao(燥), the pathology of Xiaoke(消渴) is similar to Huo(火), the pathology of Jungpung(中風).

• Asia pacific journal of information systems
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• v.15 no.3
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• pp.91-109
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• 2005

According to traditional theories of information systems, one of the reasons for using information technology is that users believe it to be helpful or useful for what they want to do, which is called extrinsic motivation. However, in addition to extrinsic motivation, there are other reasons for using it such as enjoying or playing with information technology itself, called intrinsic motivation, and just others around users, called social influence. The objective of this study is to provide a research model for using information technology considering intrinsic and extrinsic motivation, and social influence. For validation of this model, we survey the users of 'Minihompy' since it is one of the most popular blog services in Korea and there are relatively clear extrinsic and intrinsic motivation, and social influence respectively in using it. By analysing 549 valid samples by Partial Least Square(PLS), we show the suggested research model to be a valid one. That is, all hypotheses we suggested turn out to be statistically significant and $R^2$ of the dependent variable, the intention of use, explaining by the model to be higher than 40%. In addition to validation of the research model, it is found that intrinsic motivation may be more important than extrinsic motivation and social influence in using information technology.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11b
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• pp.1126-1131
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• 2001

Excessive vibration in rotating machinery is a problem encountered in many different fields, causing such difficulties as fatigue of machinery components and failure of supporting bearings. Passive techniques, though sometimes limited in their capabilities, have been used in the past to attenuated vibrations. Recently active techniques have been developed to provide vibration control perform beyond that provided by their passive counters. Most often, the focus of active control methods has been to suppress rotating machinery displacements. In cases where vibration results in bearing failures, displacement suppression may not be the best choice of control approaches (it can, in fact, increase dynamic bearing loads which would be even more harmful to bearings). This paper presents two optimal control methods for attenuating steady state vibrations in rotating machinery. One method minimizes shaft displacements while the other minimizes dynamic bearing reaction forces. The two methods are applied to a model of a typical rotating machinery system and their results are compared. It is found that displacement minimization can increase bearing loads, while bearing load minimization, on the other hand, decreases bearing loads.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.12
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• pp.465-471
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• 2021

The study investigates the dynamic correlation of cryptocurrencies and equity in Vietnam and tests the safe-haven property of them from the perspective of the stock market in Vietnam during the pandemic crisis by applying the dynamic conditional correlation (DCC) GARCH model and regression with a dummy variable, respectively. This study employs time series data on the daily dataset from September 2014 to September 2021 with the focus on the two most popular cryptocurrencies - Bitcoin and Litecoin. The results show that the dynamic conditional correlations between cryptocurrencies and equity in Vietnam increased during the pandemic, however, in most periods, positive dynamic correlations often dominate. Besides, the regression results also indicate that Bitcoin and Litecoin act as weak safe-haven investments for stocks in Vietnam during the COVID-19 turmoil. They are more suitable for diversification purposes although the dynamic correlations between them and the stock index in Vietnam vary stronger during the pandemic crisis than before. The findings of this study suggest that in the period of pandemic crisis, cryptocurrencies are not concerned as effective safe-haven assets for stock in Vietnam. Instead, cryptocurrencies are only playing a potential role in diversification benefit in this economy.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.11
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• pp.203-212
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• 2021

Theoretically, economic growth necessitates financial liberalization. Thus, the current research examines the effect of financial liberalization on economic growth in emerging nations, with a particular focus on Egypt and Saudi Arabia. To determine this effect, the study employs a model that uses Gross Domestic Product growth as the dependent variable and the following macroeconomic variables as financial liberalization indices: Broad money as a percentage of GDP, Domestic bank credit to the private sector as a percentage of GDP, Monetary sector credit to the private sector as a percentage of GDP, Net inflows of foreign direct investment as a percentage of GDP. All data is annual data of Egypt and the Kingdom of Saudi Arabia for the period 1970-2018 obtained from the World Bank open data website. The empirical investigation employs the Autoregressive Distributed Lag (ARDL) approach. The findings indicate that, after more than three decades of implementation, both countries' financial and external liberalization policies do not have a favorable effect on their economies' growth rates. Additionally, this study has led us to conclude that any financial liberalization policy in both countries must be preceded by the strengthening of these countries' financial development and institutional frameworks, as well as the achievement of macroeconomic stability.

• Asia-Pacific Journal of Business
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• v.10 no.2
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• pp.99-116
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• 2019

In this study, we examined the effects of self-efficacy and self-esteem on employment anxiety based on existing prior study and verified the moderating effect of academic stress between self-efficacy and employment anxiety, and moderating effect of academic stress between self-esteem and employment anxiety and the analysis result are as follows. The first result shows that self-efficacy and self-esteem negatively affect employment anxiety. Second, academic stress has not played a role of moderating in the relationship between self-efficacy and employment anxiety. As academic stress increases, employment anxiety increases. However, the regression analysis results confirmed that the academic stress can be an independent variable that explains employment anxiety. Finally, academic stress plays a role of moderating in the relationship between self-esteem and employment anxiety. This means that students with relatively high self-esteem are less likely to have employment anxiety than those who do not, and that increasing academic stress increases the employment anxiety of college students.

• Current Optics and Photonics
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• v.3 no.2
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• pp.177-180
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• 2019

Based on liquid-lens technology and our previous findings on the optical model of the Chinese eye, the liquid lens is applied in the research of the crystalline-lens optical model. Theoretical models of three-layer liquid lenses are built with COMSOL software, and the effect of voltage on the shape of the interface between two liquids is analyzed. By polynomial fitting, different equations describing the interface shape are set up under different voltages. Finally, the optical system of the human eye with a three-layer liquid lens is built and analyzed with Zemax optical design software, and moreover the optical system models of emmetropia, myopia, and hyperopia are presented. This method to build a model of the human eye with a variable-focus liquid lens can provide a novel idea for more practical human-eye models for clinical regulation and control in the future.

• Biomolecules & Therapeutics
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• v.27 no.1
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• pp.1-14
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• 2019

Resveratrol was first isolated in 1939 by Takaoka from Veratrum grandiflorum O. Loes. Following this discovery, sporadic descriptive reports appeared in the literature. However, spurred by our seminal paper published nearly 60 years later, resveratrol became a household word and the subject of extensive investigation. Now, in addition to appearing in over 20,000 research papers, resveratrol has inspired monographs, conferences, symposia, patents, chemical derivatives, etc. In addition, dietary supplements are marketed under various tradenames. Once resveratrol was brought to the limelight, early research tended to focus on pharmacological activities related to the cardiovascular system, inflammation, and cancer but, over the years, the horizon greatly expanded. Around 130 human clinical trials have been (or are being) conducted with varying results. This may be due to factors such as disparate doses (ca. 5 to 5,000 mg/day) and variable experimental settings. Further, molecular targets are numerous and a dominant mechanism is elusive or nonexistent. In this context, the compound is overtly promiscuous. Nonetheless, since the safety profile is pristine, and use as a dietary supplement is prevalent, these features are not viewed as detrimental. Given the ongoing history of resveratrol, it is reasonable to advocate for additional development and further clinical investigation. Topical preparations seem especially promising, as do conditions that can respond to anti-inflammatory action and/or direct exposure, such as colon cancer prevention. Although the ultimate fate of resveratrol remains an open question, thus far, the compound has inspired innovative scientific concepts and enhanced public awareness of preventative health care.