• 대한전기학회논문지
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• 제32권8호
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• pp.277-283
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• 1983

The pulse generating circuit system of the so-called turbulently-heated theta pinch is experimentally investigated, and its results are compared with the predictions based on the conventional theory. The conventional theory assumes that the impedance of the pinch coil is independent on the time rate of change in voltage (or current) across the pinch coil. The experimental pulse height of the voltage actross the pinch coil is about 1.5% fo that predicted by the conventional theory.

• 한국표면공학회지
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• 제19권2호
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• pp.51-58
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• 1986

A theoretical model was proposed to predict the rate of particles impinging on the negatively biased substrate and the total kinetic energy per unit time. The model takes into an account of kinetic theory based on Maxwell statistics and elementary plasma theory, incorporated with Hertz-Knudsen's evaporation theory. It is found that as the bias potential increases the ion flux and kinetic energy increases to a value above which the effect of potential is insignificant.

• 한국병원경영학회지
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• 제11권4호
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• pp.19-36
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• 2006

This study aims to examine the influence of growth rate, profitability and current ratio, which are confronted with static trade-off theory and pecking order theory, on capital structure of superior hospital and bankrupt hospital. Firstly, superior hospitals show positive correlation between growth rate and short-term loans, long-term loans, and short-term liabilities while bankrupt hospitals represent negative correlation. Superiority hospital and bankruptcy hospital show different financing behaviors, especially, short-term loan is the significant characteristic that discriminates between superior hospital and bankrupt hospital. Secondly, this paper studied the correlation between profitability and short-term loan, which the superior hospitals shows negative correlation, to contrast, bankrupt hospital have positive correlation. Consequently, the short-term loan is the most distinguishable factor between the superior hospital and bankrupt hospitals in terms of profitability. To conclude, this study shows that excess short-term loans can be the most important cause for hospital's bankrupt. Accordingly, strategic and effective policy about the short-term loan will be required in order to protect hospital's bankrupt.

• Wind and Structures
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• 제35권2호
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• pp.109-120
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• 2022

The force coefficients of rotating plates in the acceleration stage will vary with rotation rate from 0 to stable rotation rate w₀, which are important for quasi-steady theory of plate-like windborne debris to simulate the trajectory. In this paper, a wind tunnel experiment is carried out to study the effects of geometry and the Reynolds number on the variations of mean force coefficients of rotating plates. The rotational lift coefficients are sensitive to both geometry effect and Reynolds number effect, while the rotational drag and moment coefficients are only sensitive to geometry effect. In addition, new empirical formulas for the rotational lift coefficient and moment coefficients are proposed. Its accuracy is verified by comparing the predicted results with existing test data. Based on the experimental data of rotating plates, a new rotational force model for quasi-steady theory, which can be applied to a wider scope, is proposed to calculate the trajectory of plate-like windborne debris. The results show that the new model provides a better match with the tested trajectories than previous quasi-steady theories.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제18권8호
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• pp.2119-2136
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• 2024

The rapid progress of social media allows more people to express their feelings and opinions online. Many data on social media contains people's emotional information, which can be used for people's psychological analysis and emotional calculation. This research is based on the simplified psychological scale algorithm of multi-theory integration. It aims to accurately analyze people's psychological emotion. According to the comparative analysis of algorithm performance, the results show that the highest recall rate of the algorithm in this study is 95%, while the highest recall rate of the item response theory algorithm and the social network analysis algorithm is 68% and 87%. The acceleration ratio and data volume of the research algorithm are analyzed. The results show that when 400,000 data are calculated in the Hadoop cluster and there are 8 nodes, the maximum acceleration ratio is 40%. When the data volume is 8GB, the maximum scale ratio of 8 nodes is 43%. Finally, we carried out an empirical analysis on the model that compute the population's psychological and emotional conditions. During the analysis, the psychological simplification scale algorithm was adopted and multiple theories were taken into account. Then, we collected negative comments and expressions about Japan's discharge of radioactive water in microblog and compared them with the trend derived by the model. The results were consistent. Therefore, this research model has achieved good results in the emotion classification of microblog comments.

• 천문학회보
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• 제38권2호
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• pp.60.1-60.1
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• 2013

We study tidal disruption and subsequent mass fallback process for stars approaching supermassive black holes on bound orbits, by performing three dimensional Smoothed Particle Hydrodynamics simulations with a pseudo-Newtonian potential. We find that the mass fallback rate decays with the expected -5/3 power of time for parabolic orbits, albeit with a slight deviation due to the self-gravity of the stellar debris. For eccentric orbits, however, there is a critical value of the orbital eccentricity, significantly below which all of the stellar debris is bound to the supermassive black hole. All the mass therefore falls back to the supermassive black hole in a much shorter time than in the standard, parabolic case. The resultant mass fallback rate considerably exceeds the Eddington accretion rate and substantially differs from the -5/3 power of time. We also show that general relativistic precession is crucial for accretion disk formation via circularization of stellar debris from stars on moderately eccentric orbits.

• Bulletin of the Korean Chemical Society
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• 제35권12호
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• pp.3559-3566
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• 2014

Study on the unimolecular reaction for $CH_2FO$ and $CD_2FO$ is carried out. The structures, energy barriers and zero point energy of the three channels in the title unimolecular reactions are computed with the MP2/6-311++G(3df, 3pd) method. RRKM theory is used to calculate the rate constants of canonical case at temperature range of 500-5000 K and microcanonical system at total energy of 19.05-71.68 kcal/mol. The results indicate that the anharmonic effect and isotope effect are very small for the three channels, and the anharmonic rate constants, around $10^9-10^{11}s^{-1}$, are close to the experimental prediction reasonably.

• 대한화학회지
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• 제65권3호
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• pp.185-196
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• 2021

For studying the reaction mechanism of the reactions related to NO in the ozone denitration reactions, the harmonic and anharmonic rate constants were calculated by the transition state (TS) theory and Yao and Lin (YL) method. According to above calculations, the reactions of NO with O₃ and NO₃ play an essential role, and the kinetic parameters considering anharmonic effect were fitted. Furthermore, the rate constants were up as temperature increasing, and the tendencies of high temperature were more gradual than the low temperature. The research will provide theoretical basis for the ozone denitration reactions.

• 기술혁신학회지
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• 제11권3호
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• pp.335-351
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• 2008

본 연구는 지식기반경제에서 휴면특허(sleeping patents)의 활용이 매우 중요한 문제로 부각되고 있는 상황에서, 휴면특허에 대한 경제적 이론을 처음으로 정립하고자 하였다 휴면특허의 정의 문제로 시작하여 유형별 발생 원인을 규명하고, 경제학의 기본 개념들을 활용하여 특허의 자연휴면율 개념을 제시하였으며, 휴면특허의 사회적 손실을 측정하였다. 본 연구에서 제안된 휴면특허에 대한 개념들은 특허활용에 대한 정책적 문제들을 해결하는 데 있어서 다양한 지침을 제고해줄 것이다. 기본적으로는 휴면특허에 대한 설문조사 설계를 비롯하여 정책효과를 예측하는데도 활용할 수 있을 것이다. 가령 실증분석을 통해 특허의 자연휴면율에 대한 정보를 얻을 수 있으면, '용인할 수 있는' 휴면특허율(tolerable rate of sleeping patent)의 범위를 알 수 있고, 이에 따라 정책개입의 강도를 조절할 수 있을 것이다. 하지만 본 연구에서 사용된 용어들은 물론 휴면특허의 유형화 기준, 특허의 자연휴면율, 휴면특허의 사회적 손실 등 제시된 개념들에 대해서도 다각적인 토론이 요망된다.

• 한국산학기술학회논문지
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• 제12권12호
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• pp.5663-5670
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• 2011

이 논문은 기업의 자본조달과 자본구조를 설명하는 이론으로 대표적인 정태적 절충이론과 자본조달순위이론을 2000년부터 2010년까지 11년간의 기간에 걸쳐서 한국의 중소기업이 주로 상장되어 운영되는 코스닥시장을 대상으로 분석하였다. 코스닥 시장에 거래된 금융업을 제외한 762개의 표본에 대해 전체기간, 전반기 및 하반기의 하위기간으로 구분하여 회귀분석한 결과 부채사용으로 인한 법인세 절약효과와 기업규모 증가에 따라 부채비율이 증가하는 정태적 절충이론의 주장이 일부 지지되지만, 성장기회가 많을수록 부채사용을 선호하고, 수익성이 높을수록 유보이익과 같은 내부자금을 선호함에 따라 레버리지가 감소하는 자본조달순위이론도 일부 지지하는 결과를 얻었으나 감가상각비 등을 이용한 비부채 세금절약은 자본조달 의사결정에 영향을 미치지 않는 것으로 분석되었다.