• Structural Engineering and Mechanics
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• 제13권2호
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• pp.187-209
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• 2002

The infrastructure system in the United States has been aging faster than the resource available to restore them. Therefore decision for allocating the resources is based in part on the condition of the structural system. This paper proposes to use neural network to predict the overall rating of the structural system because of the successful applications of neural network to other fields which require a "symptom-diagnostic" type relationship. The goal of this paper is to illustrate the potential of using neural network in civil engineering applications and, particularly, in bridge evaluations. Data collected by the Tennessee Department of Transportation were used as "test bed" for the study. Multi-layer feed forward networks were developed using the Levenberg-Marquardt training algorithm. All the neural networks consisted of at least one hidden layer of neurons. Hyperbolic tangent transfer functions were used in the first hidden layer and log-sigmoid transfer functions were used in the subsequent hidden and output layers. The best performing neural network consisted of three hidden layers. This network contained three neurons in the first hidden layer, two neurons in the second hidden layer and one neuron in the third hidden layer. The neural network performed well based on a target error of 10%. The results of this study indicate that the potential for using neural networks for the evaluation of infrastructure systems is very good.

• 한국표면공학회지
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• 제45권4호
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• pp.162-167
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• 2012

Ni-P/C multi-layer was synthesized by electroless plating and paste coating for better corrosion and surface conductance as a metallic bipolar plate. The Ni-P layer could be synthesized with the range of 2.6~22.4 at.% P contents and it's surface morphology and corrosion resistance depend on content of P. Corrosion resistance of the Ni-P layer in sulfuric acid by electrochemical test is similar with pure Ni. Surface resistance of pure Ni after corrosion was increased about 8% compared to pure Ni. On the other hand, that of the Ni-P/C composite with 20% carbon content was increased only 1%.

• 전자공학회논문지
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• 제52권7호
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• pp.169-177
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• 2015

본 논문에서는 다층 의사결정을 위한 퍼지 포괄 평가 빙식을 제안하고 평가 시스템을 구축하였다. 제안한 방법은 퍼지 포괄평가 방법과 엔트로피 가중치를 이용하여 주요 평가 항목에 대해서 입찰 전에 평가하는 방식이다. 주요 평가 항목은 중요 스포츠 이벤트 조직위원들의 광범위한 조사에 의해 구성되었다. 본 논문에서는 낮은 단계에서 높은 단계로 순차적으로 단일 인자에 대한 평가와 퍼지 포괄 평가가 수행되었다. 제안한 방식의 유용성을 확인하기 위해서 후보도시의 평가를 위한 스포츠 이벤트 관리 서비스 플랫폼을 구축하였다. 이 방법은 정량적 결과와 전문가의 판단에 근거한 정성적 결과를 통합하여 출력한다.

• 예술인문사회 융합 멀티미디어 논문지
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• 제9권11호
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• pp.1015-1026
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• 2019

본 연구에서는 노인장기요양시설 평가지표개발과 관련된 선행연구의 평가현장 적용성 및 실효성이 미흡하다는 문제의식하에, 노인장기요양기관(시설급여) 평가의 품질향상을 위한 평가지표를 개발하는 데 연구의 목적이 있었다. 이를 위해 2018년도 노인장기요양기관(시설급여) 평가지표에 대한 분석적 고찰, 일본의 노인특별요양홈 평가지표에 대한 분석, 한국의 노인장기요양시설 종사자와 일본의 노인특별요양홈 종사자를 대상으로 한 평가지표 및 평가체계에 관한 FGI를 실시하였다. 연구결과를 토대로 하여 이용자가 양질의 서비스를 제공 받을 수 있도록 지원하는 측면에서 평가지표를 개발하였다. 노인의 특성, 즉 유지 및 호전되기 어려운 노인성 질환의 특성과 기관운영의 방향 및 투명성, 그리고 종말기 케어의 필요성 등을 반영하였다. 기관운영, 환경 및 안전, 수급자 권리보장, 급여제공과정, 급여제공결과를 포괄하는 43개의 평가지표를 제시하였다. 또한, 중복되고, 불필요한 평가과정을 개선하여 평가의 과정 효율성을 증가시킬 수 있는 4단계 다층평가시스템을 제안하였다.

• International Journal of CAD/CAM
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• 제3권1_2호
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• pp.67-75
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• 2003

Viewpoint-dependent feature-based modelling in computer-aided design is developed for the purposes of supporting engineering design representation and automation. The approach of this paper uses a combination of a multi-level modelling approach. This has two stages of mapping between models, and the multi-level model approach is implemented in three-level architecture. Top of this level is a feature-based description for each viewpoint, comprising a combination of form features and other features such as loads and constraints for analysis. The middle level is an executable representation of the feature model. The bottom of this multi-level modelling is a evaluation of a feature-based CAD model obtained by executable feature representations defined in the middle level. The mappings involved in the system comprise firstly, mapping between the top level feature representations associated with different viewpoints, for example for the geometric simplification and addition of boundary conditions associated with moving from a design model to an analysis model, and secondly mapping between the top level and the middle level representations in which the feature model is transformed into the executable representation. Because an executable representation is used as the intermediate layer, the low level evaluation can be active. The example will be implemented with an analysis model which is evaluated and for which results are output. This multi-level modelling approach will be investigated within the framework aimed for the design automation with a feature-based model.

• 한국정밀공학회지
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• 제32권9호
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• pp.787-792
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• 2015

Recently, 3D printing technology is a hot issue in various industrial fields. According to the user's application, it allows for the free form fabrication method to be utilized in a wide range. The powder based fusion technique is one of the 3D printing methods. When using this method it is possible to apply the various binder jetting techniques such as piezo, thermal bubble jet, dispenser and so on. In this paper, a multi thermal bubble ink jet was integrated for jetting of powder binding material and developing a power fused 3D printing system. For high quality 3D printing parts, it needs an analysis and evaluation of the behavior of the thermal bubble ink jet head. In the experiment, a correlation between jetting binder quantity and layer thickness of powder was investigated, and a 3D part model was fabricated, which was used by measuring the scale factor.

• 디지털콘텐츠학회 논문지
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• 제6권2호
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• pp.101-106
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• 2005

본 논문에서는 레일리 페이딩 채널에서 다중접속 간섭의 제거와 시스템 채널 용량의 증가를 위해 MIMO-MC/CDMA 16QAM 시스템의 모바일 액세스 계층에 대한 성능을 평가하였다. 전통적으로 무선통신에서 다중경로는 불필요한 요소로 여겨졌다. 따라서 다이버시티와 적응 어레이 방식이 다중경로를 제거하기 위하여 제안되었다. 최근에는 스펙트럼 효율과 링크의 신뢰도를 증가하기 위하여 다중경로를 이용하는 MIMO방식이 제안되었다. 특히, MIMO-MC/CDMA 16QAM 시스템의 채널 용량이 Eb/No, Mc, p에 따라서 평가되었다. 결과로부터 채널용량을 개선하기 위해서는 신호의 요소들은 서로 무상관이어야 하며 만약 부적당한 공간과 상호 결합 효과에 의하여 경로사이가 상관이 이루어지면 MIMO-MC/CDMA 16 QAM시스템의 채널 용량은 상당히 감소하게 된다.

• Journal of Magnetics
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• 제21권3호
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• pp.405-412
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• 2016

In general, surface mounted PM synchronous motors (SPMSMs) are mainly adopted as a driving motor for high-speed applications, because they have high efficiency and high power density. However, the SPMSMs have some weak points such as the increase of magnetic reluctance and additional losses as a consequence of using a non-magnetic sleeve. Especially, the magneto-motive force (MMF) in the air-gap of the SPMSMs is weakened due to the magnetically increased resistance. For that reason, a large amount of PM is consumed to meet the required MMF. Nevertheless, it cannot help using the sleeve in order to maintain the mechanical integrity of a rotor assembly in high-speed rotation. Thus, in this paper, a multi-layer interior PM synchronous motor (IPMSM) not using the sleeve is presented and designed as an alternative of a SPMSM. Both motors are evaluated by test results based on a variety of characteristics required for an air blower system of a fuel cell electric vehicle.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2004년도 추계학술대회 논문집
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• pp.345-351
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• 2004

This Paper describes a nonlinear adaptive noise filter using neural network for digital controller system. Back-Propagation Learning Algorithm based MLP (Multi Layer Perceptron)is used an adaptive filters. In this paper. it assume that the noise of primary input in the adaptive noise canceller is not the same characteristic as that of the reference input. Experimental reaults show that the neural network base noise canceller outperforms the linear noise canceller. Especially to make noise cancel close to realtime, Primary input is divided by unit and each divided part is processed for very short time than all the processed data are unified to whole data.

• 한국지하수토양환경학회지:지하수토양환경
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• 제21권1호
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• pp.1-5
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• 2016

Capillary barriers, consisting of relatively fine-over-coarse materials, have been suggested as an alternative to traditional compacted soil covers. So, We were analysed to capillary barrier effect according to five cases of multi-layer cover systems. Water balance simulation was conducted with unsaturated flow model HELP to assess unsaturated hydraulic parameters such as hydraulic conductivity, climate affecting the performance of capillary barriers. Simulation were conducted for 5 Cases in the Ulsan area. Result of simulation indicated that three cases was formed unsaturated condition and capillary barrier effect.