• 국제학술발표논문집
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• The 5th International Conference on Construction Engineering and Project Management
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• pp.133-140
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• 2013

The purpose of this study is identifying the relationship among the business strategy, order receiving capability and leverage variables of a construction company using industry characteristic variables, in addition to the explanation variables used in the previous studies. The samples of this study were limited to the construction companies listed in Korean stock market. This study built multiple regression analysis models, which have been frequently used in traditional previous studies, in the explanation of company capital structure. Empirical analysis on Static Trade-off Theory and Pecking Order Theory was done by the built model. The study results suggested that the capital structure determination behavior of a construction company generally follows Static Trade-off Theory; however, profitability was found to follow Pecking Order Theory. The explanation variables used in the previous capital structure studies mostly produced significant results; however, the variables, which this study experimentally used, did not produce significant results. It is believed that it implies that additional studies are required in the selection of variables and study methodology. Consequently, a case that unconditionally supports a particular theory is scarce. It has been also found that a case can support both theories at the same time. Therefore, it is believed that development study methodology or introduction of new study methodology that can identify the dynamic characteristic of construction company capital structure formation is required.

• 한국통신학회논문지
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• 제17권11호
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• pp.1290-1298
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• 1992

본 논문은 fitting 파라미터를 배제하고 2차원적 Poisson 방정식을 도출해서 short-channel MOSFET의 model 식을 완전히 해석적으로 성립시켰다. 이로 인해 포화영역, 문턱전압, 강반전에 대한 것이 동시에 표현되는 정확한 드레인 전류가 유도되었다. 더욱이 이 model은 short-channel과 body효과, DIBL효과, 그리고 carrier운동에 대한 것도 설명할 수 있으며 온도와 $n^+$접합, 산화층에 관련되는 문턱전압도 표현할 수 있었다.

• Journal of Ecology and Environment
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• 제29권4호
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• pp.361-364
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• 2006

The objective of the current study was to characterize and apply multiple regression model relating to vegetation values of the plant species over salt marshes. For each salt marsh community, vegetation and soil variables were investigated in the western coast and the southern coast in South Korea. Osmotic potential of soil and $Cl^-$ content of soil as independent variable had positive and negative influences on vegetation values. Multiple regression model showed that vegetation values of 14 coastal plant communities were determined by pH of soil, osmotic potential of soil and sand content. The multiple regression equation may be applied to the explanation of distribution and abundance of plant communities with exiting ordination plots.

• 디지털산업정보학회논문지
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• 제20권1호
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• pp.31-45
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• 2024

The purpose of this study is to explain employment factors in the software field. For it, the Graduates Occupational Mobility Survey by the Korea employment information service is used. This paper proposes employment models in the software field using machine learning. Then, it explains employment factors of the models using explainable artificial intelligence. The models focus on both university graduates and vocational college graduates. Our works explain and interpret both black box model and glass box model. The SHAP and EBM explanation are used to interpret black box model and glass box model, respectively. The results describes that positive employment impact factors are major, vocational education and training, employment preparation setting semester, and intern experience in the employment models. This study provides a job preparation guide to universitiy and vocational college students that want to work in software field.

• 대한교통학회지
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• 제10권3호
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• pp.103-122
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• 1992

The objective of this research is to develop a traffic accident forecasting model using traffic accident data in pusan from 1963 to 1991 and then to make short-term forecasts('93~'94) of traffic accidents in pusan. In this research, several forecasting models are developed. They include a multiple regression model, a time-series ARIMA model, a Logistic curve model, and a Gompertz curve model. Among them, the model which shows the most significance in forecasting accuracy is selected as the traffic accident forecasting model. The results of this research are as followings. 1. The existing model such as Smeed model which was developed for foreign countries shows only 47.8% explanation for traffic accident deaths in Korea. 2. A nonliner regression model ($R^2$=0.9432) and a Logistic curve model are appeared to be th gest forecasting models for the number of traffic accidents, and a Logistic curve model shows th most significance in predicting the accident deaths and injuries. 3. The forecasting figures of the traffic accidents in pusan are as followings: . In 1993, 31, 180 accidents are predicted to happen, and 430 persons are predicted to be deaths and 29, 680 persons are predicated to be injuries. . In 1994, 33, 710 accidents are predicted to happen, and 431.persons are predicted to be deat! and 30, 510 persons are predicted to be injuried. Therefore, preventive measures against traffic accidents are certainly required.

• 대한화학회지
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• 제68권2호
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• pp.107-116
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• 2024

본 연구의 목적은 테크놀로지를 활용한 모델의 평가와 수정 과정에서 나타난 예비화학교사들의 모델의 본성에 대한 인식 변화를 분석하는 것이다. 모델의 본성에 대한 인식 변화는 선행연구에서 예비화학교사들에게 부족하다고 판단된 표상적 측면의 함축화와 간단화, 설명적 측면의 해석, 추론, 설명, 정량화를 중심으로 분석하였다. 이를 위하여 충청북도에 있는 사범대학의 3학년 예비화학교사 19명을 대상으로 테크놀로지를 활용하여 개발한 보일 법칙 관련 모델을 평가하고, 평가 결과를 바탕으로 모델을 수정하여 최종 평가하도록 요구하였다. 연구 결과, 표상적 측면의 간단화, 설명적 측면의 해석, 설명, 정량화에 대한 예비화학교사들의 인식이 모델의 평가와 수정 과정을 통해 긍정적으로 변화되었음을 확인할 수 있었다. 따라서 모델의 본성에 대한 인식이 변화하기 위해서는 모델의 평가와 수정 과정이 핵심적인 역할을 하는 것을 알 수 있었다. 하지만 표상적 측면의 함축화와 설명적 측면의 추론에 대한 인식 변화는 거의 나타나지 않았다. 이러한 요소들에 대한 인식은 다른 요소들의 인식보다 변화하기 어려운 것으로 볼 수 있다. 이러한 문제를 해결하기 위해서는 예비화학교사들을 위한 보다 정교한 교육 설계가 필요하다.

• Journal of Photoscience
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• 제3권3호
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• pp.147-151
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• 1996

Dynamics of contact ion-pair between 1, 2, 4, 5-tetracyanobenzene anion and cation of biphenyl derivatives was investigated on the picosecond time scale. Solvent effect on the electron transfer was observed and electron transfer rates were examined using Marcus equation which contains distance dependence of the electron transfer rate in the frequency factor, along with the consideration of molecular shape. From the discussion based on disk model for molecular shape, contribution of interring torsional motion of biphenyl to the inner-sphere reorganization energy is strongly suggested, which leads to the physical explanation for the observed solvent effect on the rate of electron transfer.

• Transactions on Electrical and Electronic Materials
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• 제8권2호
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• pp.79-83
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• 2007

The implications of a theory of lubricated pad asperity wafer contact are traced through several fundamental areas of chemical-mechanical polishing. The hypothesized existence of a nanolubrication layer underlies a high accuracy model of polish rates. It also provides a quantitative explanation of a power law relationship between the coefficient of friction and a measure of pad surface flattening. The theory may further be useful for interpreting friction changes during polishing, and may explain why the coefficient of friction is sometimes observed to have a temperature or velocity dependence.

• 생물정신의학
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• 제26권2호
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• pp.33-38
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• 2019

Psychiatric disorder as dysfunctional behavioural syndrome is a paradoxical phenomenon that is difficult to explain evolutionarily because moderate prevalence rate, high heritability and relatively low fitness are shown. Several evolutionary genetic models have been proposed to address this paradox. In this paper, I explain each model by dividing it into selective neutrality, mutation-selection balance, and balancing selection hypothesis, and discuss the advantages and disadvantages of them. In addition, the feasibility of niche specialization and frequency dependent selection as the plausible explanation about the central paradox is briefly discussed.

• 지구물리
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• 제6권4호
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• pp.221-230
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• 2003

Many hydraulic structures are damaged by under flood flow and storm waves year after year. Many cases of dike and breakwater failure are caused by the suck out of sand from behind the revetment. This type of failure will be in close relation to the dynamic behavior of sand bed around the revetment. In this paper, from this point of view we investigated the basic characteristics of such sand movement by small model tests and tried to explanation the hydro- and soil mechanical mechanism of this phenomenon theoretically.