• Proceedings of the Korea Society for Simulation Conference
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• 1992.10a
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• pp.1-1
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• 1992

This paper presents a user-oriented port expansion simulation model that determines the future economic port capacity to meet the projected demand. The model consists of two parts; a physical impact simulation, and an economic impact simulation. The first part of the model simulates the effects caused by the port capacity expansion. The second part evaluates the port economics due to changes in the port capacity. The model was validated by applying it to the actual port expansion followed at the Port of Mobile, Alabama. A case study is then presented to demonstrate the capacity of the model with a coal handling port, the McDuffie Terminals at the Port of Mobile.

• Radiation Oncology Journal
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• v.24 no.4
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• pp.280-284
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• 2006

$\underline{Purpose}$: To evaluate biological characteristics of neutron beam generated by MC50 cyclotron located in the Korea Institute of Radiological and Medical Sciences (KIRAMS). $\underline{Materials\;and\;Methods}$: The neutron beams generated with 15 mm Beryllium target hit by 35 MeV proton beam was used and dosimetry data was measured before in-vitro study. We irradiated 0, 1, 2, 3, 4 and 5 Gy of neutron beam to EMT-6 cell line and surviving fraction (SF) was measured. The SF curve was also examined at the same dose when applying lead shielding to avoid gamma ray component. In the X-ray experiment, SF curve was obtained after irradiation of 0, 2, 5, 10, and 15 Gy. $\underline{Results}$: The neutron beams have 84% of neutron and 16% of gamma component at the depth of 2 cm with the field size of $26{\times}26\;cm^2$, beam current $20\;{\mu}A$, and dose rate of 9.25 cGy/min. The SF curve from X-ray, when fitted to linear-quadratic (LQ) model, had 0.611 as ${\alpha}/{\beta}$ ratio (${\alpha}=0.0204,\;{\beta}=0.0334,\;R^2=0.999$, respectively). The SF curve from neutron beam had shoulders at low dose area and fitted well to LQ model with the value of $R^2$ exceeding 0.99 in all experiments. The mean value of alpha and beta were -0.315 (range, $-0.254{\sim}-0.360$) and 0.247 ($0.220{\sim}0.262$), respectively. The addition of lead shielding resulted in no straightening of SF curve and shoulders in low dose area still existed. The RBE of neutron beam was in range of $2.07{\sim}2.19$ with SF=0.1 and $2.21{\sim}2.35$ with SF=0.01, respectively. $\underline{Conclusion}$: The neutron beam from MC50 cyclotron has significant amount of gamma component and this may have contributed to form the shoulder of survival curve. The RBE of neutron beam generated by MC50 was about 2.2.

• 한국IT서비스학회:학술대회논문집
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• 2005.05a
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• pp.381-389
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• 2005

정보시스템 구축비용의 급격한 증가로, 정보시스템 성과 분석은 이슈가 되고 있고, 정보시스템의 중요성과 이에 대한 의존성은 날로 증가하고 있다. 현재까지 정보시스템 성과에 관해서는 기존 연구들을 정리한 DeLone & McLean(1992)의 정보시스템 성공 모형(IS Success Model)을 근거로 이를 구성하는 각 요소들을 검증하거나 영역을 확장하고자 하는 연구들이 진행되어왔다. 본 연구에서는 DeLone & McLean(1992)의 정보시스템 성공 모형(IS Success Model)을 기반으로 특정 정보시스템 담당자들을 대상으로 정보시스템의 품질, 이용, 효과에 관한 연관관계를 실증 분석하였다.

• Journal of Plant Biology
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• v.21 no.1_4
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• pp.33-38
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• 1978

Phosphate absorption from a Na2H32PO4 solution by Oryza sativa L. was studied in order to elucidate kinetic mechanisms of ion transport. The rates of phosphate absorption from different concentraitons indicated the presence of dual mechanisms in root tips, one in the low (1$\times$10-6 to 8$\times$10-5M) and the other in the high (1$\times$10-4 to 8$\times$10-3M). A phosphate compensation point of phosphate transport was revealed with a 1$\times$10-6M solution of Na2H32PO4. The kinetic model that ion transport involves an exchange reaction of absorption and desorptin is prosposed as follows: where C represents an ionic-specific organic carrier in the membrane; M, Mo and Mi are the mineral ions, M-outside and M-inside; MC is a carrier-ion complex; and the K's represent rate constants. In this model, the Mi velocity, v, is given by: {{{{v= {dMi} over {dt}= {(K1K3Mo-K2K4Mi) Ct} over {(K2＋K3)＋K1Mo＋K4Mi} }} where Ct is equal to C＋MC, and t is time.

• Environmental and Resource Economics Review
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• v.10 no.2
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• pp.259-279
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• 2001

This paper investigates the optimal ratio of the ex post cost settled in the total cost paid to the facility-operating agent and the size of compensation for demand promotion efforts made by the trustee. We have extended McAfee and McMillan(1986)'s principal-agent model by incorporating incentives for the demand promotion efforts. We show that cost reducing effort is negatively related with the ratio of the ex post cost settled in the total cost. In addition, the optimal level of demand promotion effort is determined by the size of the compensation and the ratio of the ex post cost settled. A simulation study confirms our findings from a theoretical model.

• Korean Journal of Agricultural Science
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• v.19 no.2
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• pp.179-186
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• 1992

This experiment was carried out to study the drying characteristics of model foods containing moisture, protein and starch on different concentration of additives such as sodium chloride and sucrose. Textural properties of model foods were measured by using UTM(instron). The results obtained are summaried as follows: As starch content and solute concentration of model foods increase, drying time was extended. The multiple regression equations for drying characteristics of additive concentration ($X_1$, %), drying time ($X_3$, hr), drying temperature ($X_2$, OC), starch content($X_4$, %) are : $$E(MC)=58.282-5.197X_3-15.151X_4-0.145X_2+2.672X_1\;R^2=0.798\;(NaCl)$$ $$E(MC)=56.651-7.253X_3-0.183X_2-42.844X_1+3.025X_4\;R^2=0.858\;(Sucrose)$$ As starch content, drying temperature and solute concentation increased, he hard ness of model foods increased.

• Korean Journal of Cognitive Science
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• v.2 no.2
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• pp.487-513
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• 1990

The present paper reviews experimental finding such as kanji stroop effect, kana superiority effect in naming task, kanji superiority effect in lexical devision task, and the different pattern of facilitatory priming effect in repetition priming task. Most of the experimental findings indicate that kana script and kanji script are processed independently and modularly. These indications are also consistent with the basic observations on Japanese dyslexics. A connectionist model named JIA(Japanese Interactive Activation)is proposed which is a revision of interactive activation model proposed by McClelland & Rumelhart(1981). The differences between the two models are as follows. Firstly, JIA has a kana module and kanji module at letter level. Secondly, JIA adopts script-specific interconnections between letter-level nodes and word-level nodes:word nodes receive larger activation from the script consistent letter-level nodes. JIA successfully explains all the experimental findings and many cases of Japanese dyslexia. A computer program which simulates JIA model was written and run.

• Knowledge Management Research
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• v.15 no.3
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• pp.13-36
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• 2014

Recently, with the increasing popularity of smartphones, mobile applications have been being used in various sectors. In these environments, some mobile applications are being made for special purposes. The mobile campus application is one exemplary type of such special-purpose mobile applications, which have unique characteristics that allow only designated users, belonging to a specific group, to access and use relevant knowledge. The aim of this study is to identify and investigate critical success factors of mobile campus applications based on the DeLone & McLean's information systems (IS) success model and to find unique characteristics of mobile campus applications, compared to general-purpose mobile applications. In order to empirically test our research model, 199 samples were collected from students who actually had experience of using the mobile campus application of A university at least once. The findings of the structural equation modeling using SmartPLS 2.0 confirmed the DeLone & McLean's IS success model, with the exception for relationships between service quality and user satisfaction/intention to use. Moreover, the moderating role of sense of belonging to school on the relationships between quality-related factors (i.e., information, system, and service qualities) and success-related factors (i.e., user satisfaction and intention to use) was examined.

• The Korean Journal of Applied Statistics
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• v.18 no.2
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• pp.435-443
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• 2005

Coefficients of determination in logistic regression analysis are defined as various statistics, and their values are relatively smaller than those for linear regression model. These coefficients of determination are not generally used to evaluate and diagnose logistic regression model. Liao and McGee (2003) proposed two adjusted coefficients of determination which are robust at the addition of inappropriate predictors and the variation of sample size. In this work, these adjusted coefficients of determination are applied to variable selection method for logistic regression model and compared with results of other methods such as the forward selection, backward elimination, stepwise selection, and AIC statistic.

• Journal of KSNVE
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• v.8 no.1
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• pp.157-170
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• 1998

This paper proposes a new technique to formulate the finite element model of a sandwich beam by using GHM (Golla-Hughes-McTavish) internal auxiliary coordinates to account for frequency dependence. Through the use of auxiliary coordinates, the equation of motion of undamped mass and stiffness matrix form is extended to encompass viscoelastic damping matrix. However, this methods all suffer from an increase in order of the final finite element model which is undesirable in many applications. Here we propose to combine the GHM method with model reduction techniques to remove the objection of increased model order.