• Journal of Digital Convergence
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• v.16 no.3
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• pp.543-552
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• 2018

The purpose of this study is to provide basic data for the improvement of the tournament operating environment and effective tournament operation. For the factor analysis, exploratory factor analysis was conducted. Based on this, in order to conduct hierarchical analysis, we've produced and distributed the questionnaire to expert group. And after, with collected data, AHP (Analytical Hierarchy Process) technique was used to analyze relative importance and determinants. As a result, operational factors showed the highest priority among the components of evaluation. And next prior factors are satisfaction of participants, environmental factors and etc. In order to stabilize the operation of the tournament, priority shall be securing the budget. And it is necessary to understand the desire of participants and shall consider characteristics and level of the tournament. In future studies, it will be necessary to make a comparative study through expert group in order to secure the fitness.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.4
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• pp.425-429
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• 2011

In the unlikely of nuclear reactor meltdown, the leaked core melt or corium must be contained in a device called core-catcher so that the corium can be cooled and stabilized. The ex-vessel behavior of corium involves complex physical and chemical mechanisms of flow propagation, heat transfer, and reactions with sacrificial substrates. In this study, the detailed characteristics of corium flow and heat transfer were investigated by using a commercial CFD code for VULCANO VE-U7 test reported in the literature. The volume-of-fluid (VOF) model was used to predict the interfacial surface formation of corium and the surrounding air, and the discrete ordinate model was adopted to calculate radiation between corium and the surroundings. It was found that cooling via radiation through the top surface of corium had a dominant effect on the temperature and viscosity profiles at the front of the corium flow.

• Ecology and Resilient Infrastructure
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• v.7 no.1
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• pp.15-25
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• 2020

We've compared and conceptually evaluated the newly emerging concept of nature-based solutions (NbS's), in the aspect of water management, and existing similar solutions of different naming, all of which are based on ecosystem functions. In this study, it is found that NbS's seem significant and meaningful both educationally and understandably in the aspect that it can comprehensively cover and include the existing methodologies and solutions using the functions of natural ecosystem to socio-environmental challenges. It, however, seems not quite different from the broad-meaning of green infra, including Eco-DRR, in terms of the approaching methodologies in water management. The conceptual and spatial hierarchy of each practice in water management considered in this study can be expressed in the narrowing order of NbS-(EE)-BGI-(CRT)-GI-LID. Last, the term LID, which is the best management practice for storm water management in the development project, can be replaced with the term GI for clarification and less confusion both in academia and practice.

• Journal of the Korean Geotechnical Society
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• v.27 no.12
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• pp.69-84
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• 2011

This paper presents the applicability of NATM Composite Lining method in domestic tunnel construction sites. Firstly, in order to produce high quality PC Panel, optimal steam curing condition is reviewed. And in preparation for fire inside the tunnel, the fire-resistance test of PC Panel is carried out. The constructability of NATM Composite Lining method and the drainage ability of light-weight foamed mortar is also evaluated through field construction test. And PC Panel combination program is developed to calculate the quantity of PC Panel efficiently. Besides, economic evaluation for NATM Composite Lining method is conducted. From this research, it is clearly found that NATM Composite Lining method is applicable to domestic tunnel construction site.

• KIPS Transactions on Software and Data Engineering
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• v.9 no.5
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• pp.153-160
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• 2020

Energy Consumption Predictions for Industries has a prominent role to play in the energy management and control system as dynamic and seasonal changes are occurring in energy demand and supply. This paper introduces and explores the steel industry's predictive models of energy consumption. The data used includes lagging and leading reactive power lagging and leading current variable, emission of carbon dioxide (tCO2) and load type. Four statistical models are trained and tested in the test set: (a) Linear Regression (LR), (b) Radial Kernel Support Vector Machine (SVM RBF), (c) Gradient Boosting Machine (GBM), and (d) Random Forest (RF). Root Mean Squared Error (RMSE), Mean Absolute Error (MAE) and Mean Absolute Percentage Error (MAPE) are used for calculating regression model predictive performance. When using all the predictors, the best model RF can provide RMSE value 7.33 in the test set.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.39 no.5
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• pp.45-55
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• 2002

In this paper, we describe an outdoor augmented reality system using GPS tracking for position and attitude information. The system consist of a remote mobile operation unit and a ground operation unit. The remote mobile operation unit includes a real-time image acquiring device, a GPS tracking device, and a wireless data transceiver; the ground operation unit includes a wireless transceiver, a virtual image generating device, and an image superimposing device. The GPS tracking device for measurement of position and attitude of the remote mobile operation unit was designed by TANS Vector and RT-20 for DGPS. The wireless data transceiver was for data transmission between the remote mobile operation unit and the ground operation unit. After the remote mobile operation unit was installed on a vehicle and a helicopter, the system was evaluated to verify its validity in actual applications. It was found that the implemented system could be used for obtaining real-time remote information such as construction simulation, tour guide, broadcasting, disaster observation, or military purpose.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.46 no.5
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• pp.91-100
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• 2009

In this paper, we propose a wearable augmented reality system using gaze interaction. Gaze interaction has been considered to be the potential of easy, natural and fast way of interaction and becomes a suitable way in optical see-through HMD based wearable AR. Our system recognizes user's gaze point, half blink motion and displays the information of object seen by user to HMD. Half blink selection technique avoids the Midas touch problem and represents user's intention correctly. We've developed a AR annotation system and estimated the usability of gaze interaction. The accuracy and robustness of our technique is verified on the experimental results.

• Food Science and Preservation
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• v.14 no.3
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• pp.332-335
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• 2007

Hot water and 95%(v/v) ethanol extracts were prepared from dried Lespedeza cuneata seeds and antioxidant compounds were isolated by solvent fractionation, silica gel adslorption chromatography, Sephadex LH-20 column chromatography, and preparative HPLC. Antioxidant activity was measured using DPPH radical scavenging activity. The 80%(v/v)ethanol and ethylacetate fraction of Lespedeza cuneata seed extracts had stronger antioxidant effects than did the n-hexane fraction. The active antioxidant compounds obtained from hot water and 95%(v/v) ethanol extracts may be identical, based on analysis by Sephadex LH-20 column chromatography and preparative HPLC.

• Journal of Practical Engineering Education
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• v.8 no.2
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• pp.121-128
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• 2016

In injection molding process, the appearance quality issue occurs in most injection molded article. One of thermal designs for the mold was performed by increasing the cavity wall temperature with being as uniform as possible in any position. On the basis of the practical evaluation, the cavity wall temperature and finishing machined cavity surface under the optimum processing conditions are the most significant factors to avoid the appearance issue on the plastic part for a good cosmetic quality. Also, the wrong choice of gate type and location can have a considerable effect on the quality of a molded part and it's so important to keep the correct runner balance from each cavity. We've proposed the education training model of the practical tool technology course for the field oriented education to improve practical tool technology ability and optimized tooling design for injection molding quality which can be performed at the workplace substantially.

• Journal of Chest Surgery
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• v.29 no.12
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• pp.1347-1353
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• 1996

To assess the long-term results of mitral valve replacement, we reviewed our cases of the 374 patients undergoing mitral valve replacement between March 1982 to February 1992 There were 159 male and 215 female and mean age was 37.8 years. There were 24 hospital deaths(6.4%);the most commonly from low cardiac output syndrome(12 deaths). We used 314 mechanical valves and 60 tissue valves. Most of all were anticoagulated with coumadin maintaining target level of 1.5~3.0 INR of prothrombin time. Follow up was 94% complete(2270 patient-years). There were 12 late deaths 3 due to hemorrhage, 3 due to cerebral embolism and 6 from Overall actuarial survival including hospital mortality, was 82.3% after 10 years of operation Linealized rates of late complication events are follows thromboembolism, 1.3% per patient-year; anti coagulant related hemorrhage, 0.5% per patient year. We analyzed the factors of favorable effect to postoperative course were preoperat ve clinical status including NYHA class, first operation, valve apparatus preservating operation technique, not biggest size of prosthetic valve.