• Journal of Digital Convergence
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• v.15 no.3
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• pp.157-163
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• 2017

Forecasting container cargo volumes is very important factor for port related organizations in inversting in the recent port management. Especially forcasting of domestic and foreign container volume is necessary because adjacent nations are competing each other to handle more container cargoes. Exact forecasting is essential elements for national port policy, however there is still some difficulty in developing the predictive model. In this respect, the purpose of this study is to develop and suggest the forecasting model of container cargo volumes of China using System Dynamics (SD). The monthly data collected from Clarkson's Shipping Intelligence Network from year 2004 to 2015 during 12 years are used in the model. The accuracy of the model was tested by comparisons between actual container cargo volumes and forecasted corgo volumes suggested by the research model. The MAPE values are calcualted as 6.21% for imported cargo volumes and 7.68% for exported cargo volumes respectively. Less than 10% of MAPE value means that the suggested model is very accurate.

• Clinical and Experimental Pediatrics
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• v.45 no.10
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• pp.1298-1301
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• 2002

Systemic capillary leak syndrome(SCLS) is a rare disorder of unknown etiology, which is characterized by recurrent attacks of hypotension, hemoconcentration, and hypoalbuminemia. Urinary or enteric loss of protein is not demonstrated. It is often associated with monoclonal gammopathy, but does not manifest multiple myeloma. Since Clarkson et al. described the first case in a 34-year-old woman, about 50 cases have been reported in the literature. However, most of the cases were of adult age, and the mean age of onset in the reported cases was 42.6 years. In literature review, we could refer only one pediatric case of SCLC by Foeldvari et al. in 1995. We report another pediatric case of SCLS.

• International Journal of Aeronautical and Space Sciences
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• v.13 no.2
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• pp.210-220
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• 2012

The model-free control of aeroelastic vibrations of a non-linear 2-D wing-flap system operating in supersonic flight speed regimes is discussed in this paper. A novel continuous robust controller design yields asymptotically stable vibration suppression in both the pitching and plunging degrees of freedom using the flap deflection as a control input. The controller also ensures that all system states remain bounded at all times during closed-loop operation. A Lyapunov method is used to obtain the global asymptotic stability result. The unsteady aerodynamic load is considered by resourcing to the non-linear Piston Theory Aerodynamics (PTA) modified to account for the effect of the flap deflection. Simulation results demonstrate the performance of the robust control strategy in suppressing dynamic aeroelastic instabilities, such as non-linear flutter and limit cycle oscillations.

• International Journal of Aeronautical and Space Sciences
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• v.12 no.2
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• pp.179-189
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• 2011

In this paper, robust adaptive control design problem is addressed for a class of parametrically uncertain aeroelastic systems. A full-state robust adaptive controller was designed to suppress aeroelastic vibrations of a nonlinear wing section. The design used leading and trailing edge control actuations. The full state feedback (FSFB) control yielded a global uniformly ultimately bounded result for two-axis vibration suppression. The pitching and plunging displacements were measurable; however, the pitching and plunging rates were not measurable. Thus, a high gain observer was used to modify the FSFB control design to become an output feedback (OFB) design while the stability analysis for the OFB control law was presented. Simulation results demonstrate the efficacy of the multi-input multi-output control toward suppressing aeroelastic vibrations and limit cycle oscillations occurring in pre- and post-flutter velocity regimes.

• Journal of Information Processing Systems
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• v.4 no.2
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• pp.41-52
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• 2008

In this paper, we discuss a novel reservation-based, asynchronous MAC protocol called 'Multi-rate Multi-hop MAC Protocol' (MMMP) for multi-hop ad hoc networks that provides QoS guarantees for multimedia traffic. MMMP achieves this by providing service differentiation for multirate real-time traffic (both constant and variable bit rate traffic) and guaranteeing a bounded end-to-end delay for the same while still catering to the throughput requirements of non real time traffic. In addition, it administers bandwidth preservation via a feature called 'Smart Drop' and implements efficient bandwidth usage through a mechanism called 'Release Bandwidth'. Simulation results on the QualNet simulator indicate that MMMP outperforms IEEE 802.11 on all performance metrics and can efficiently handle a large range of traffic intensity. It also outperforms other similar state-of-the-art MAC protocols.

• Journal of the Korean Institute of Gas
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• v.10 no.2 s.31
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• pp.55-60
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• 2006

Detailed modeling of PEMFCs has been getting considerable interest for predicting the fuel cell performance and also for use in various systems engineering activities. While CFD-based equipment models provide detailed analyses of the performance, they are very time-consuming to develop and run. The computations become quite complex when such models have to be embedded into the flowsheet-level optimization of fuel cell systems. In this paper, we present results about building and using NN-based reduced order models for quickly and repetitively predicting the flow of reactants in a PEMFC manifold.

• The Journal of Korean Society for Radiation Therapy
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• v.2 no.1
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• pp.87-92
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• 1987

The authors have intended to measure intrinsic dose distribution by Farmer dosimeter in irregularly shaped fields such as L, M, T,-shape model in order to determine dose inhomogeneity in those models. We made 2 off-axis points in each model and measured the depth dose at 1.5,5, and 9cm below surface. The results showed $1-3\%$ dose discrepancy between 2 points. We also measured the depth dose by geometric approximation and computer calculation in those models, and came to the conclusion that computer calculation using Clarkson's principle is simpler and the measurements are to the ideal data obtained by the experiment in those three models of irregularly shaped fields than those of geometric approximation method.

• Radiation Oncology Journal
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• v.2 no.2
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• pp.281-285
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• 1984

The authors have intended to measure intrinsic dose distribution by Farmer dosimeter in irregularly shaped fields such as L.M and T shape models in order to determine dose inhomogeneity in those models. We made 2 off·axis points in each model and measured the depth dose at 1.5, 5 and 9cm below surface. The results showed $l\~3\%$ dose discrepancy between 2 points. We also measured the depth dose by geometric approximation and computer calculation in those models, and came to the conclusion that computer calculation using Clarkson's principle is simpler and the measurements are closer to the ideal data obtained by the experiment in three models of irregularly shaped fields than those of geometric approximation method.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.153-154
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• 2003

최근 10년간 대기환경 개선대책으로 1차 오염물질인 이산화황과 총부유먼지(TSP)의 농도는 현저히 감소하고 있다. 그러나 자동차의 증가 등으로 미세먼지, 오존 둥 2차 대기오염물질의 오염도는 오히려 증가하고 있는 추세에 있다. 특히 미세먼지(PM$_{2.5}$)는 시정에 영향을 주어 체감오염도를 증가시킬 뿐만 아니라 PM$_{2.5}$ 내에 함유된 각종 유해물질과 중금속 등은 인체에 직접적인 영향을 주는 것으로 알려져 있다. (중략)(중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.39-40
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• 2001

최근 들어서 환경유해물질이 인체의 건강에 미치는 영향에 대한 관심이 커지고 있다. 특히 환경 중에 존재하는 발암성 물질에 대한 연구가 활발히 진행되면서 이들 물질에 의한 인체에 미치는 위해성이 밝혀지고 있다. Polycyclic Aromatic Hydrocarbons(PAHs)는 환경에 존재하는 중요한 발암물질, 돌연변이 유도체이다. PAHs는 여러 종류의 배출원이나 배출원 가까이 있는 환경에서만 발견되는 것이 아니라, 장기간에 걸쳐 대기 중에서 멀리 운반되어 전세계적으로 확산되어진다. 건식 침적은 대기중 PAHs의 주요 제거기작 중 하나이다. (중략)