• Bulletin of the Korean Chemical Society
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• 제4권5호
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• pp.223-227
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• 1983

A molecular dynamic computer experiment was performed on a system of 108 particles composed of a single polymer chain and solvent molecules. The state considered was in the immediate neighborhood of the triple point of the system. The polymer itself is an analog of a freely jointed chain. The Lennard-Jones potential was used to represent the interactions between all particles except for that between the chain elements forming a bond in the polymer chain, for which the interaction was expressed by a harmonic potential. The self-diffusion coefficient and velocity autocorrelation function (VACF) of a polymer were calculated at various chain lengths $N_p$, and various interaction strengths between solvent molecules and a polymer chain element. For self-diffusion coefficients D, the Einstein relation holds good; as chain length $N_p$ increases the D value decreases, and D also decreases as ${\varepsilon}_{cs}$ (the interaction parameter between the chain element and solvent molecules) increases. The relaxation time of velocity autocorrelation decreases as ${\varepsilon}_{cs}$ increases, and it is constant for various chain lengths. The diffusion coefficients in various conditions reveal that our systems are in a free draining limit as is well known from the behavior of low molecular weight polymers, this also agrees with the Kirkwood-Riesman theory.

• Journal of Contemporary Eastern Asia
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• 제20권1호
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• pp.1-23
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• 2021

With regard to the recent developments in public diplomacy, the increasing fusion of strategic communication appears necessary. China engages in public diplomacy with a strategic purpose to shape its national image abroad. Hosting diplomatic advocacy event is regarded as an instrument with expectations to present reliable and responsible image and promote international collaborations. The present research focuses on the Belt and Road Forum (BRF) in May 2017 with the objective to analyze its outcomes and influence on the international news agenda, news frames, and foreign citizens' comments online. The quantitative content analyses are used to compare the media reports (N=364) and Facebook users' comments on the selected news (N=957) between the US and Pakistan. Results reveal that Pakistani media provided more diverse frames and attributed more positive evaluations to the BRF than the US media. However, Facebook comments expressed more unfavorable opinions toward the BRF and China's image with rare differences between two countries. In conclusion, the BRF has served as an eye-catching advocacy of Chinese foreign policy, as it influenced the news agenda in two selected countries. However, news frames vary due to the differences in media system and the involvement in the BRF. China's public diplomacy practices follow a traditional top-down communication which needs meticulous subdivision of target stakeholders, delicate messaging strategies, and integrated tactics.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 B
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• pp.1015-1017
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• 2002

This is the study on static excitation system of synchronous generator of large capacity in new model, which was developed by KEPRI using triple redundant digital method, associate three bridges of thyristor phase controlled rectifier. This paper will discuss the design conception and the application results of system which includes the power control devices(thyristors, GTO) and power excitation potential transformer. The multi-paralleling thyristor bridge converters of N+1 method have firing circuit. The initial product manufactured by proposed design in the study is in commercial operation, completing installation and commissioning in 400MW Thermal Power Plant. The performance test is done in practical technique.

• Interaction and multiscale mechanics
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• 제1권2호
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• pp.191-209
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• 2008

In this paper, we model grain boundary evolution based on a multiple level set method. Grain boundary migration under a curvature-induced driving force is considered and the level set method is employed to deal with the resulting topological changes of grain structures. The complexity of using a level set method for modeling grain structure evolution is due to its N-phase nature and the associated geometry compatibility constraint. We employ a multiple level set method with a predictor-multicorrectors approach to reduce the gaps in the triple junctions down to the grid resolution level. A ghost cell approach for imposing periodic boundary conditions is introduced without solving a constrained problem with a Lagrange multiplier method or a penalty method. Numerical results for both uniform and random grain structures evolution are presented and the results are compared with the solutions based on a front tracking approach (Chen and Kotta et al. 2004b).

• Journal of Contemporary Eastern Asia
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• 제16권1호
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• pp.82-92
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• 2017

The objective of this study is to analyze the relationship between organizational capacity and the use of firefighter volunteers by volunteer fire departments within local/county governments. The study is based on a nonrandom sample of 213 U.S. volunteer fire departments within local governments. The fire chief of these fire departments responded to an annual survey conducted by Firehouse Magazine in 2010 and 2011. This study uses OLS regression analysis to assess the impact of organizational capacity (measured as annual budget) on the number of firefighter volunteers used by the volunteer fire department. There is evidence to suggest that organizational capacity has a positive and statistically significant effect on the number of volunteers used among U.S. volunteer fire departments. This study extends current literature on public volunteerism by analyzing factors that explain variation in the use of volunteers by local governments, specifically fire departments. Findings suggest that fire departments with greater resources in terms of revenue are more likely to use volunteers.

• ETRI Journal
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• 제39권4호
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• pp.455-466
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• 2017

This study focuses on a method for sequential data augmentation in order to alleviate data sparseness problems. Specifically, we present corpus expansion techniques for enhancing the coverage of a language model. Recent recurrent neural network studies show that a seq2seq model can be applied for addressing language generation issues; it has the ability to generate new sentences from given input sentences. We present a method of corpus expansion using a sentence-chain based seq2seq model. For training the seq2seq model, sentence chains are used as triples. The first two sentences in a triple are used for the encoder of the seq2seq model, while the last sentence becomes a target sequence for the decoder. Using only internal resources, evaluation results show an improvement of approximately 7.6% relative perplexity over a baseline language model of Korean text. Additionally, from a comparison with a previous study, the sentence chain approach reduces the size of the training data by 38.4% while generating 1.4-times the number of n-grams with superior performance for English text.

• 한국컴퓨터정보학회논문지
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• 제6권2호
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• pp.70-77
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• 2001

본 연구에서 통신상에서의 각종 보안 위협에 안전한 POS System을 설계, 구현하였다. 연구에 적용된 암호 알고리즘은 RSA, MD5, 3중DES가 있으며. RBAC를 모델로 한 역할기반 접근통제제어를 구현하였다. 클라이언트 프로그램과 서버 프로그램의 데이터 송수신이 이루어지기 전의 클라이언트 사용자 인증과 송수신 데이터의 기밀성과 무결성 유지에 암호 알고리즘이 적용되었다. 본 논문에서는 클라이언트 사용자의 데이터 접근을 통제하기 위하여 역할기반 접근 통제 제어모델이 적용되었다. 개발된 프로그램을 실제 업무에 적용하여 안정성을 입증하였다.

• Communications for Statistical Applications and Methods
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• 제5권2호
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• pp.539-557
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• 1998

This article is concerned with the problem of estimating the mean of a one-parameter exponential family through sequential sampling in three stages under quadratic error loss. This more general framework differs from those considered by Hall (1981) and others. The differences are : (i) the estimator and the final stage sample size are dependent; and (ii) second order approximation of a continuously differentiable function of the final stage sample size permits evaluation of the asymptotic regret through higher order moments. In particular, the asymptotic regret can be expressed as a function of both the skewness $\rho$ and the kurtosis $\beta$ of the underlying distribution. The conditions on $\rho$ and $\beta$ for which negative regret is expected are discussed. Further results concerning the stopping variable N are also presented. We also supplement our theoretical findings wish simulation results to provide a feel for the triple sampling procedure presented in this study.

• 대한전자공학회논문지
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• 제27권12호
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• pp.1870-1877
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• 1990

The electromagnetic properties of P- and n-channel split drain magnetic sensitive MOSFET fabricated using 2\ulcorner design rules and CMOS process technology has been investigated. The achieved output voltage in the double drain MOSFET was 160mV at 10\ulcorner drain current and magnetic flux density of 10kG, and the sensitivity was 1.6x10**3 V/A\ulcornerG. A further higher sensitivity was obtained by introducing a third drain in the split region. In this case, the triple drain MOSFET showed a much higher sensitivity of 2x10**3 V/A\ulcornerG under the same condition. Also, the linearity of output voltage vs. magnetic flux density was excellent.

• E2M - 전기 전자와 첨단 소재
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• 제7권2호
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• pp.123-129
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• 1994

SONOS EEPROM chips, containing several SONOSFET nonvolatile memories of various channel size, have been fabricated on the basis of the existing n-well CMOS processing technology for 1 Mbit DRAM ($1.2\mu\textrm{m}$.m design rule). All the SONOSFET memories have the triple insulated-gate consisting of 30.angs. tunneling oxide, 205.angs. nitride and 65.angs. blocking oxide. The miniaturization of the devices for the higher density EEPROM and their characteristics alterations accompanied with the scaling-down have been investigated. The stabler operating characteristics were attained by increasing the ratio of the channel width to length. Also, the transfer, switching, retention and degradation characteristics of the most favorable performance devices were presented and discussed.