• Journal of Korean Association for Spatial Structures
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• v.15 no.4
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• pp.73-80
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• 2015

The new rotary friction damper was developed using several two-nodal rotary frictional components with different clamping forces. Because of these components, the rotary friction damper can be activated by building movements due to lateral forces such as a wind and earthquake. In this paper, various dependency tests such as displacement amplitude, forcing frequency and long term cyclic loading were carried out to evaluate on the structural performance and the multi-slip mechanism of the new damper. Test results show that the multi-slip mechanism is verified and friction coefficients are dependent on displacement amplitute and forcing frequency except long term cyclic loading.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.8
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• pp.580-583
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• 2012

The dependency of processing pressure on the electrical performances in amorphous silicon-zinc-tin-oxide thin film transistors (SZTO-TFT) has been investigated. The SZTO channel layers were deposited by using radio frequency (RF) magnetron sputtering method with different partial pressure. The field effect mobility (${\mu}_{FE}$) increased and threshold voltage ($V_{th}$) shifted to negative direction with increasing pressure during deposition processing. As a result, oxygen vacancies generated in SZTO channel layer with increasing partial pressure resulted in negative shift in $V_{th}$ and increase in on-current.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.20 no.4
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• pp.429-437
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• 2013

Purpose: The purpose of this study was to identify factors influencing nicotine dependency among college students intending to quit smoking, and to provide data for the construction of programs that will be successful in helping the students quit smoking. Method: In this study a cross-sectional survey to analyze was used. The data were collected between April 22 and April 24, 2013 from 218 college students who had unsuccessfully tried to quit smoking in the past but were now intending to try and quit smoking again. Data were analyzed using frequency, independent t-test, one-way ANOVA and multiple regression with the SPSS 21.0. Results: Factors influencing nicotine dependency were self-efficacy for smoking abstinence (t=-6.60, p=<.001), length of time since beginning to smoke (t=5.39, p<.001), level of carbon monoxide intake (t=2.38, p=.018), and withdrawal symptoms as reasons why the students failed to quit smoking (t=2.22, p=.028). These 4 variables accounted for 35.0% of the variance with regard to nicotine dependency. Conclusions: To conduct a successful program for students who intend to quit smoking, self-efficacy for smoking abstinence, length of time since beginning to smoke, level of carbon monoxide, and withdrawal symptoms as reasons for failing to quit smoking should be considered.

• Journal of the Korea Convergence Society
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• v.9 no.1
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• pp.213-221
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• 2018

The purpose of this study was to verify the impact of maltreatment by parents on adolescents' depression, furthermore, confirm the mediating effects of social withdrawal and cell phone dependency in South Korea. The data were analyzed with frequency, correlation and structural equation modeling(SEM) by SPSS 18.0 and AMOS 20.0. Data was employed from the wave 5 in 2014 of Korean Children and Youth Panel Study (KCYPS), and analyzed data of 1,969 fourth grade elementary school students. The result showed: First, maltreatment experience from parents has a statistically significant positive effect on adolescent's depression. Second, maltreatment experience from parents has positive effects on both social withdrawal and mobile phone dependency. Third, both social withdrawal and mobile phone dependency have positive effects on adolescent's depression. Fourth, both social withdrawal and mobile phone dependency have significant mediating roles in the relationship between maltreatment experience from parents and adolescent's depression.

• The Journal of the Korea Contents Association
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• v.10 no.11
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• pp.30-37
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• 2010

It is very important to analyze online customer reviews, which are small documents of writing opinions or experiences about products or services, for both customers and companies because the customers can get good informations and the companies can establish good marketing strategies. In this paper, we did not propose only dependency network model which is tool for analyzing online customer reviews, but also designed and implemented the system based on the dependency network model. The dependency network model analyzes both subjective and objective sentences, so that it can represent relative importance and relationship between the nouns in the sentences. In the result of implementing, we recognized that relative importance and relationship between the features of products or services, which can not be mined by opinion mining, can be represented by the dependency network model.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2003.03a
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• pp.77-84
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• 2003

For stochastic strong ground motion simulation, frequency-dependent Q model (= $Q_{o}$ $f^{η}$) were evaluated for major geographical blocks according to the epicentral distance ranges by using a lateral Q tomography technique. The inversed Q results were used to qualitatively identify seismic albedos of each Q blocks and were compared with the previous Q studies. In addition, a functional Q model calibrated to the low frequency spectra of local earthquakes were suggested especially for use in analysing large and distant regional earthquake events.s.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.5
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• pp.515-521
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• 2021

The popularity of Islamic financial instruments among Muslims is not surprising. The Islamic capital market is where sharia-compliant financial assets are transacted. It works parallel to the conventional market and helps investors find sharia-compliant investment opportunities. At a time of collective confusion when the COVID-19 epidemic is contributing to unprecedented change, this paper is keen to understand how attractive conventional and Islamic stock markets have been to investors recently. Second, this paper takes advantage of the time-scale decomposition property of the wavelet to simultaneously capture risk exposure and distinguish the risks faced by short- and long-term investors. To this end, this research conducted a two-step investigation of the daily closing equity market price indices for three Islamic stock markets and their conventional counterparts. Given that different financial decisions occur with greater or less frequency, the paper examines the connectedness of stock markets operating at heterogeneous rates and identifies the timescales using wavelet-DCC-GARCH analysis to take account of both the time and the frequency domains of stock market connectedness. The paper findings highlight the strong evidence of contagion that can be seen in nearly all conventional stock markets in the COVID-19 pandemic; they reach a high level of dependency in such health crises. Furthermore, Islamic stock markets prove to be a rich ground for global diversification.

• Progress in Superconductivity and Cryogenics
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• v.4 no.1
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• pp.140-144
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• 2002

A free piston and free displacer (FPFD) Stirling cryocooler has been widely used for the cooling infrared and cryo-sensor. The thermodynamic performance of the free piston and free displacer type (FPFD) Stirling cryocooler is highly dependent on the operating frequency of the linear compressor and the natural frequency of the displacer. In this study, to find optimal relation between operating and natural frequency of the displacer the dynamic characteristics of the displacer in the expansion space of the Stirling cooler was investigated by experiment. The experimental results show that the Stifling cryocooler has maximum cooling capacity at the operating frequency of about 0.8 times of the natural frequency of displacer. Therefore the operating frequency of the Stirring cryocooler should be determined by natural frequency of the linear compressor and displacer.

• Proceedings of the IEEK Conference
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• 2000.07a
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• pp.129-131
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• 2000

A new analog synchronous mirror delay to be used in the wide-bandwidth clocking circuits is proposed to overcome the frequency dependency of the negative-delay values in the conventional analog synchronous mirror delay. The scheme adopts a new dummy-delay compensation technique by adopting the comparator with inherent systematic offset to achieve the enhanced negative-delay range especially prominent at high frequency applications.

• Nuclear Engineering and Technology
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• v.52 no.10
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• pp.2238-2249
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• 2020

In a seismic PSA, dependency among seismic failures of components has not been explicitly modeled in the fault tree or event tree. This dependency is separately identified and assigned with numbers that range from zero to unity that reflect the level of the mutual correlation among seismic failures. Because of complexity and difficulty in calculating combination probabilities of correlated seismic failures in complex seismic event tree and fault tree, there has been a great need of development to explicitly model seismic correlation in terms of seismic common cause failures (CCFs). If seismic correlations are converted into seismic CCFs, it is possible to calculate an accurate value of a top event probability or frequency of a complex seismic fault tree by using the same procedure as for internal, fire, and flooding PSA. This study first proposes a methodology to explicitly model seismic dependency by converting correlated seismic failures into seismic CCFs. As a result, this methodology will allow systems analysts to quantify seismic risk as what they have done with the CCF method in internal, fire, and flooding PSA.