• Geomechanics and Engineering
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• 제11권3호
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• pp.361-372
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• 2016

The soil-concrete interface shear strength, although has been extensively studied, is still difficult to predict as a result of the dependence on many factors such as normal stresses, surface roughness, particle sizes, moisture contents, dilation angles of soils, etc. In this study, a well-known rigorous statistical learning approach, namely the least squares support vector machine (LS-SVM) realized in a ubiquitous spreadsheet platform is firstly used in estimating the soil-structure interface shear strength. Instead of studying the complicated mechanism, LS-SVM enables to explore the possible link between the fundamental factors and the interface shear strengths, via a sophisticated statistic approach. As a preliminary investigation, the authors study the expansive soils that are found extensively in most countries. To reduce the complexity, three major influential factors, e.g., initial moisture contents, initial dry densities and normal stresses of soils are taken into account in developing the LS-SVM models for the soil-concrete interface shear strengths. The predicted results by LS-SVM show reasonably good agreement with experimental data from direct shear tests.

• 대한지리학회지
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• 제36권4호
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• pp.402-417
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• 2001

본 연구에서는 사업서비스 분야 한국내 외국인직접투자가 지역경제에 미치는 영향을 분석하였으며, 특히, 지역네트워크와 지식의 활용이라는 측면에서 파악하였다. 외국인직접투자기업은 한국내 시장확보라는 투자동기에 따라 고객과의 네트워크, 공급 네트워크는 높은 비중을 나타내고 있으나, 상대적으로 산학연계 및 협회, 조합, 정부기관과의 관계는 낮게 나타난다. 한국내 지식이전 및 상호작용도 투자모기업의 정책에 따라 제한적으로 이루어지고 있다. 그러나, 협력관계 및 인력이동 등 장기적으로 볼 때 긍정적인 측면과 가능성도 보이고 있어, 지식활용에 기반한 정책지원 및 활용안을 수립하여 실천한다면, 외국인기업이 충분히 지역내 뿌리내리며, 지역경제에 기여할 수 있을 것이다.

• The Journal of Asian Finance, Economics and Business
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• 제7권4호
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• pp.197-203
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• 2020

This study investigates graduate competencies that can improve the uptake of higher education graduate outcomes in the working environment in Indonesia. This research was conducted by collecting data through sending questionnaires directly by the research team, via courier, or via postal service to respondents. A survey with questionnaire is carried out on April 2019, and the data from 117 respondents was analyzed. The sample population was all private higher education in the area of the I-XIV Higher Education Service Institution in Indonesia. This study employs factor analysis and structural equation modelling. The results show that the Graduates' competencies had a significant direct effect on the uptake of higher education graduates in the job market. The indirect effect of a Diploma Supplement and networking as mediation has a level of influence that is higher than the direct effect of graduate competence on the uptake of higher education graduate outcomes in the job market. The findings suggest that the Diploma Supplement and networking can increase the uptake of higher education graduates in Indonesia as expected by stakeholders and be able to compete in the global or international scale of environmental working. The professionalism of lecturers has a significant influence on the quality of learning.

• 대한간호학회지
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• 제34권1호
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• pp.172-181
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• 2004

Purpose: This study was designed to construct a structural model for explaining negative outcomes of anger in female adolescents. Methods: Data was collected by questionnaires from 199 female adolescents ina female high school in Seoul. Data analysis was done with SAS for descriptive statistics and a PC-LISREL Program for Covariance structural analysis. Results: The fit of the hypothetical model to the data was moderate, thus it was modified by excluding 7 paths and adding free parameters to it. The modified model withthe paths showed a good fit to the empirical data($x^2$ =5.62, p=.69, GFl=.99, AGFl=.97, NFI=.99, NNFI=l.01, RMSR=.02, RMSEA=.00). Trait anger, state anger, and psychosocial problems were found to have a significant direct effect on psychosomatic symptoms. State anger, psychosocial problems, and learning behaviorswere found to have direct effects on depression of female adolescents. Conclusion: The derived modelis considered appropriate for explaining and predicting negative outcomes of anger in female adolescents. Therefore, it can effectively be used as a reference model for further studies and is a suggested direction in nursing practice.

• 조명전기설비학회논문지
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• 제25권5호
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• pp.22-33
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• 2011

An induction motor operated with a conventional direct self controller(DSC) shows a sluggish response during startup and under changes of torque command. Fuzzy logic controller(FLC) is used in conjection with DSC to minimize these problems. A FLC chooses the switching states based on a set of fuzzy variables. Flux position, error in flux magnitude and error in torque are used as fuzzy state variables. Fuzzy rules are determinated by observing the vector diagram of flux and currents. This paper proposes hybrid fuzzy controller for direct torque control(DTC) of induction motor drives. The speed controller is based on adaptive fuzzy learning controller(AFLC), which provide high dynamics performances both in transient and steady state response. Flux position, error in flux magnitude and error in torque are used as FLC state variables. The speed is estimated with model reference adaptive system(MRAS) based on artificial neural network(ANN) trained on-line by a back-propagation algorithm. This paper is controlled speed using hybrid fuzzy controller(HFC) and estimation of speed using ANN. The performance of the proposed induction motor drive with HFC controller and ANN is verified by analysis results at various operation conditions.

• 한국정보통신학회논문지
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• 제17권5호
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• pp.1106-1112
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• 2013

키넥트는 이용자의 신체를 이용하여 게임과 엔터테인먼트를 경험할 수 있는 주변기기로 2010년 초 마이크로소프트사에서 발표하여 공개하였다. 본 논문은 키넥트에서 제공하는 세 가지 센서를 이용한 동작 인식 기능을 이용한 기타리듬 게임의 개발과 관련 기술에 대하여 다룬다. 리듬 게임은 게임의 여러 장르 중에서 매우 단순하고 학습기간이 짧으며, 신체의 활발한 활동성과 리듬성을 이용하기 때문에 피씨, 콘솔기기, 스마트폰 등 다양한 기기에서도 널리 활용되고 있는 장르이다. 본 논문에서 구현한 리듬게임은 화면구성과 게임화면을 DirectX 11버전에서 구현하였으며, 키넥트를 이용하여 게이머의 손동작 인식을 수행하기 위하여 OpenNI API를 사용하였으며 신체 움직임을 표현하기 위하여 OpenGL 라이브러리를 사용하였다.

• 대한지구과학교육학회지
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• 제14권3호
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• pp.267-276
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• 2021

이 연구의 목적은 계절별 별자리 실험에 대해 알아보고, 학교 급별로 효과적인 계절별 별자리 실험이 무엇인지 연구하는데 있다. 초등 예비교사 24명과 함께 계절별 별자리 실험을 정리하고, 학교 급별로 효과적인 실험이 무엇인지 쓰도록 하였다. 그 결과 초등학교에서는 역할놀이를 통한 직접적인 체험활동을 통한 별자리 학습이 가장 효과적이었고, 중·고등학교에서는 stellarium 프로그램을 이용하여 사실적으로 계절별 별자리의 변화를 관찰하고 추리해보는 활동을 효과적인 실험으로 선택하였다. 예비교사는 초등학교에서는 직접적인 체험과 구체적인 조작활동이 강조되는 실험을, 중·고등학교에서는 사실적인 자연현상의 관찰과 이를 통한 추리 활동이 강조되는 실험이 효과적이라고 인식하였다.

• Journal of Korea Trade
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• 제25권4호
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• pp.37-59
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• 2021

Purpose - Although models of innovation and exporting dominate recent studies of relations between innovation and access to foreign markets, relations between innovation and foreign direct investment (FDI) are less explored. This is especially true of relations between types of innovation and FDI. We fill that gap in the literature with empirical evidence that clarifies whether firms enter foreign markets through exports or FDI. Design/methodology - In order to assess the role of innovation in firms' international engagement strategies, we develop research hypotheses and present new empirical evidence on firms' choice of entry - exports and FDI - based on firm-level data. Findings - Our empirical results suggest that the impact of product innovation is more significant in transition from being a purely domestic firm to an exporter, while process innovation more significantly affect transition from being an exporter to a multinational enterprise. Our results also support 'self-selection into FDI' rather than 'learning-by-performing FDI' in the relationship between innovation and firms' overseas expansion. Originality/value - Recent literature on the relationship between innovation and firms' participation in foreign markets is dominated by models of innovation and export behavior. However, foreign direct investment by multinational enterprises may also be associated with firms' innovative activities. We first analyze how product and process innovations influence firms' choices to initiate exports or FDI.

• Nuclear Engineering and Technology
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• 제52권9호
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• pp.1998-2008
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• 2020

Solenoid operated valves (SOV) play important roles in industrial process to control the flow of fluids. Solenoid valves can be found in so many industries as well as the nuclear plant. The ability to be able to detect the presence of faults and predicting the remaining useful life (RUL) of the SOV is important in maintenance planning and also prevent unexpected interruptions in the flow of process fluids. This paper proposes a fault diagnosis method for the alternating current (AC) powered SOV. Previous research work have been focused on direct current (DC) powered SOV where the current waveform or vibrations are monitored. There are many features hidden in the AC waveform that require further signal analysis. The analysis of the AC powered SOV waveform was done in the time and frequency domain. A total of sixteen features were obtained and these were used to classify the different operating modes of the SOV by applying a machine learning technique for classification. Also, a deep neural network (DNN) was developed for the prediction of RUL based on the failure modes of the SOV. The results of this paper can be used to improve on the condition based monitoring of the SOV.

• Membrane and Water Treatment
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• 제9권6호
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• pp.455-462
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• 2018

The measurement and monitoring of the biochemical oxygen demand (BOD) play an important role in the planning and operation of wastewater treatment plants. The most basic method for determining biochemical oxygen demand is direct measurement. However, this method is both expensive and takes a long time. A five-day period is required to determine the biochemical oxygen demand. This study has been carried out in a wastewater treatment plant in Turkey (Hurma WWTP) in order to estimate the biochemical oxygen demand a shorter time and with a lower cost. Estimation was performed using artificial neural network (ANN) method. There are three different methods in the training of artificial neural networks, respectively, multi-layered (ML-ANN), teaching learning based algorithm (TLBO-ANN) and artificial bee colony algorithm (ABC-ANN). The input flow (Q), wastewater temperature (t), pH, chemical oxygen demand (COD), suspended sediment (SS), total phosphorus (tP), total nitrogen (tN), and electrical conductivity of wastewater (EC) are used as the input parameters to estimate the BOD. The root mean squared error (RMSE) and the mean absolute error (MAE) values were used in evaluating performance criteria for each model. As a result of the general evaluation, the ML-ANN method provided the best estimation results both training and test series with 0.8924 and 0.8442 determination coefficient, respectively.