• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.173-173
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• 2000

Multilayered films (MLF) consisting of transition metals and semiconductors have drawn a great deal of interest because of their unique properties and potential technological applications. Fe/Si MLF are a particular topic of research due to their interesting antiferromagnetic coupling behavior. although a number of experimental works have been done to understand the mechanism of the interlayer coupling in this system, the results are controversial and it is not yet well understood how the formation of an iron silicide in the spacer layers affects the coupling. The interpretation of the coupling data had been hampered by the lack of knowledge about the intermixed iron silicide layer which has been variously hypothesized to be a metallic compound in the B2 structure or a semiconductor in the more complex B20 structure. It is well known that both magneto-optical (MO0 and optical properties of a metal depend strongly on their electronic structure that is also correlated with the atomic and chemical ordering. In order to understand the structure and physical properties of the interfacial regions, Fe/Si multilayers with very thin sublayers were investigated by the MO and optical spectroscopies. The Fe/si MLF were prepared by rf-sputtering onto glass substrates at room temperature with a totall thickness of about 100nm. The thicknesses of Fe and Si sublayers were varied from 0.3 to 0.8 nm. In order to understand the fully intermixed state, the MLF were also annealed at various temperatures. The structure and magnetic properties of Fe/Si MLF were investigated by x-ray diffraction and vibrating sample magnertometer, respectively. The MO and optical properties were measured at toom temperature in the 1.0-4.7 eV energy range. The results were analyzed in connection with the MO and optical properties of bulk and thin-film silicides with various structures and stoichiometries.

• Journal of Korean Academy of Nursing Administration
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• v.8 no.3
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• pp.361-372
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• 2002

Purpose : The purpose of study was to identify to analysis of core nursing interventions performed by Operating Room nurses. Method : The subjects of the study were arbitrarily selected nurses(n=104) working in Operating Room. The period for data collection was 15 days from July, 15, 2002 to July, 30. 2002. The instrument for study was 486 Nursing Interventions Classification developed by McClosky & Bulechek(2000) and was translated into Korean. In 486 nursing interventions, 57 nursing interventions were selected by more than half of 47 professional nurses group of Operating Room. 57 nursing interventions were used as a secondary questionnaire. In the secondary questionnaire, labels and definitions of all 57 interventions were listed. The collected data were self reported by Operating Room nurses. The data were analysed with SPSS program. Result : In 57 nursing interventions, the 'Behavior' domain was the most frequently used. Core interventions of Operating Room were performed several times a day by more than 50% of Operating Room nurses. Core interventions of Operating Room were 16 Core interventions, 7 classes, 5 domains. In the core interventions, the 'Physiological:Complex' domain was the most frequently used. Core interventions of Operating Room were Surgical Preperation, Infection Control:Intraoperative, Surgical Precautions, Fall Prevention, Documentation, Surgical Assistance, Environmental Management:Safety, Skin Surveillance, Physical Restraint, Pressure Ulcer Prevention, Environmental Management:Comfort, Infection Protection, Presence, Emotional Support, Specimen Management, Shift Report. Conclusion : Core interventions of Operating Room have implications for nursing care practice, nursing education, nursing research, and nursing information system in Operating Room.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.17 no.3
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• pp.775-793
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• 2023

Human decision-making is a complex behavior. A replication of human decision making offers a potential to enhance the capacity of intelligent systems by providing additional user assistance in decision making. By reducing the effort and task complexity on behalf of the user, such replication would improve the overall user experience, and affect the degree of intelligence exhibited by the system. This paper explores individuals' decision-making processes when using recommender systems, and its related outcomes. In this study, human decision-making (HDM) refers to the selection of an item from a given set of options that are shown as recommendations to a user. The goal of our study was to identify IS constructs that contribute towards such decision-making, thereby contributing towards creating a mental model of HDM. This was achieved through recording Electroencephalographic (EEG) readings of subjects while they performed a decision-making activity. Readings from 16 righthanded healthy avid readers reflect that reward, theory of mind, risk, calculation, task intention, emotion, sense of touch, ambiguity and decision making are the primary constructs that users employ while deciding from a given set of recommendations in an online bookstore. In all 10 distinct brain areas were identified. These brain areas that lead to their respective constructs were found to be cingulate gyrus, precentral gyrus, inferior parietal lobule, posterior cingulate, medial frontal gyrus, anterior cingulate, postcentral gyrus, superior frontal gyrus, inferior frontal gyrus, and middle frontal gyrus (also referred to as dorsolateral prefrontal gyrus (DLPFC)). The identified constructs would help in developing a design theory for enhancing user assistance, especially in the context of recommender systems.

• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.2
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• pp.83-90
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• 2010

The windshield wiper consists of 4 parts: a blade, an arm, a linkage and a motor. The wiper blade makes contact with the windshield and is designed to be operated normally at an angle of 30~50 degrees to the front glass. If the contact pressure between the wiper blade and windshield surface is too high, noise and wear of the rubber will result. On the other hand, if the contact pressure is too low, the performance will do badly, since foreign substances such as dust and stains will not be removed well. The pressure and friction of the wiper blade has a great influence on its effectiveness in cleaning the front window. This is due to the contact of the rubber with the window. This paper presents the dynamic analysis method to estimate the performance of the flat type blade of the wiper system. The blade has a nonlinear characteristic since the rubber is an incompressible hyper-elastic and visco-elastic material. Thus, Structural dynamic analysis using a complex contact model for the blade is performed to find the characteristics of the blade. The flexible multi-body dynamic model is verified by the comparison between test and analysis result. Also, the optimization using the central composite design table is performed.

• Journal of the Korea Society for Simulation
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• v.21 no.1
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• pp.55-68
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• 2012

Recently it is important to understand service supply chain because the economy moves from manufacturing to services. However, most of existing supply chain research focuses exclusively on the manufacturing sector. To overcome this situation, it needs to investigate and analyze service supply chain. Simulation is one of the most frequently used techniques for analysis and design of complex system. Service supply chain is complex and large systems that require an accurate designing phase. Especially, it is important to examine closely the dynamically interactive behavior of the different service supply chain components in order to predict the performance of the servcie supply chain. In this paper, we develop a conceptual model of service supply chain. Then, we present a new procedure to develop simulation model for the developed conceptual model of service supply chain, based on the UML analysis and design tools and on the ARENA simulation language. The two main characteristics of the proposed procedure are the definition of a systematic procedure to design service supply chain and of a set of rules for the conceptual model translation in an ARENA simulation language. The goal is to improve the knowledge on service supply chain management and support the simulation model development efficiency on service supply chain.

• YAKHAK HOEJI
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• v.39 no.2
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• pp.161-168
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• 1995

Brain dopamine systems play a central role in the control of movement, hormone release, and many complex behavior. The action of dopamine at its synapse is terminated predominately by high affinity reuptake into presynaptic terminals by dopamine transporter (DAT). The dopamine transporter(DAT) is membrane protein localized to dopamine-containing nerve terminals and closely related with cocaine abuse, Parkinsonism, and schizophrenia. In present study, the recombinant plasmid pRc/CMV-DAT, constructed by subcloning of a cDNA encoding a bovine DAT into eukaryotic expression vector pRc/CMV, was stably transfected into CV-1 cells(monkey kidney cell line). The DAT activities in the cell lines selected by Geneticin$^{R}$ were determined by measuring the uptake of $[^3H]$-dopamine. The transfected cell lines showed 30-50 fold higher activities than untransfected CV-1 cell line, and this result implies that DAT is well expressed and localized in transfected cells. The transfected cells accumulated $[^3H]$-dopamine in a dose-dependent manner with a $K_{m}$ of 991.6nM. Even though high doses of norepinephrine, epinephrine, serotonin, and choline neurotransmitters inhibited the uptake of $[^3H]$-dopamine, DAT in transfected cell line was proven to be much more specific to dopamine. The psychotropic drugs such as GBR12909, CFT, normifensine, clomipramine, desipramine, and imipramine inhibited significantly the dopamine uptake in tissue culture cells stably transfected with DAT cDNA. Radioactive in situ hybridization was done to map the cellular localization of DAT mRNA-containing cells in the adult rat central nervous system. The strong hybridization signals were detected only in the substantia nigra pars compacta and ventral tegmental area. The restricted anatomical localization of DAT mRNA-containing cells confirms the DAT as a presynaptic marker of dopamine-containing cells in the rat brain.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.05a
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• pp.408-411
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• 2009

In this paper, conventional PI, fuzzy neural network(FNN) and adaptive teaming mechanism(ALM)-FNN for rotor field oriented controlled(RFOC) induction motor are studied comparatively. The widely used control theory based design of PI family controllers fails to perform satisfactorily under parameter variation nonlinear or load disturbance. In high performance applications, it is useful to automatically extract the complex relation that represent the drive behaviour. The use of learning through example algorithms can be a powerful tool for automatic modelling variable speed drives. They can automatically extract a functional relationship representative of the drive behavior. These methods present some advantages over the classical ones since they do not rely on the precise knowledge of mathematical models and parameters. Comparative study of PI, FNN and ALM-FNN are carried out from various aspects which is dynamic performance, steady-state accuracy, parameter robustness and complementation etc. To have a clear view of the three techniques, a RFOC system based on a three level neutral point clamped inverter-fed induction motor drive is established in this paper. Each of the three control technique: PI, FNN and ALM-FNN, are used in the outer loops for rotor speed. The merit and drawbacks of each method are summarized in the conclusion part, which may a guideline for industry application.

• Journal of Technologic Dentistry
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• v.44 no.1
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• pp.15-23
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• 2022

Purpose: The purpose of this study was to identify the experiences of depression, suicidal thoughts, and habitual drug use in middle and high school students and examine their relationship with the oral symptoms experiences. Methods: The participants of this study were 54,948 middle and high school students who took the screening and health survey at the 16th "Youth Health Behavior Survey" (2020). The SPSS statistical software (IBM SPSS 23.0 for Windows; IBM) was used for data analysis. The significance level was set to 0.05. Results: Complex-sample logistic regression analysis was performed to confirm the relationship between the experiences of depression, suicidal thoughts, and habitual drug use and oral symptom experienced. The results indicated that the absence of depression, suicidal thoughts, or habitual drugs had a significant effect on oral symptom experience. Conclusion: A systematic counseling program for early detection of oral symptoms and oral health promotion as well as strategies for practicing correct oral hygiene are required. Additionally, it is necessary to develop a customized education program to promote health education in middle and high school students. It can be used as the basis for an integrated support system that students can use to grow healthy. A differentiated program on the topic of mental health promotion for each grade can be planned and its effects can be monitored.

• Journal of Korea Water Resources Association
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• v.42 no.9
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• pp.725-736
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• 2009

A flood event can be defined by three characteristics; peak discharge, total flood volume, and flood duration, which are correlated each other. However, a conventional flood frequency analysis for the hydrological plan, design, and operation has focused on evaluating only the amount of peak discharge. The interpretation of this univariate flood frequency analysis has a limitation in describing the complex probability behavior of flood events. This study proposed a bivariate flood frequency analysis using a Gumbel mixed model for the flood evaluation. A time series of annual flood events was extracted from observations of inflow to the Soyang River Dam and the Daechung Dam, respectively. The joint probability distribution and return period were derived from the relationship between the amount of peak discharge and the total volume of flood runoff. The applicability of the Gumbel mixed model was tested by comparing the return periods acquired from the proposed bivariate analysis and the conventional univariate analysis.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.5
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• pp.611-617
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• 2010

A complex system involves a large number of design variables, and its operation is non-linear. To explore the characteristics in its design space, a Kriging meta-model can be utilized; this model has replaced expensive computational analysis that was performed in traditional parametric design optimization. In this study, a Kriging meta-model with a computational orthogonal array for the design of experiments was developed to optimize the fatigue life of a turbine blade whose behavior under cyclic rotational loads is significantly non-linear. The results not only show that the maximum fatigue life is improved but also indicate that the accuracy of computational analysis is achieved. In addition, the robustness of the results obtained by six-sigma optimization can be verified by comparison with the results obtained by performing Monte Carlo simulations.