• 융합신호처리학회논문지
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• 제14권2호
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• pp.105-109
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• 2013

There are the free space model, the direct-path and ground reflected model, Egli model, Okumura-Hata model in the representative propagational models. The measured results at the area of PNG area were used as the experimental data in this paper. The new proposed partial interval analysis method is applied on the measured propagation data in the cellular band. The interval for the analysis is divided from the entire 30 Km distance to 5 Km, and next to 1 Km. The best-fit propagation models are chosen on all partial intervals. The means and standard deviations are calculated for the differences between the measured data and all partial interval models. By using the 5 Km- or 1 Km- partial interval analysis, the standard deviation between the measured data and the partial propagation models was improved more than 1.7 dB.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2004년도 가을 학술발표회 논문집
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• pp.270-277
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• 2004

In this paper, path-independent values of the J-integral in the fininte element context for arbitrary two-dimensional and three-dimensional crack configurations in welds are presented. For the fracture mechanics analysis of cracks in welds, residual stress analysis and fracture analysis must be performed simultaneously. In the analysis of cracked bodies containing residual stress, the usual domain integral formulation results in path-dependent values of the J-integral. This paper discusses modifications of the conventional J-integral that yield path independence in the presence of residual stress generated by welding. The residual stress problem is treated as an initial strain problem and the J-integral modified for this class of problem is used. And a finite element program which can evaluate the J-integral for cracks in two-dimensional and three-dimensional residual stress bearing bodies is developed using the modified J-integral definition. The situation when residual stress only is present is examed as is the case when mechanical stresses are applied in conjunction with a residual stress field.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2011년도 춘계 학술논문 발표대회 1부
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• pp.181-184
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• 2011

The earlier studies which are related to conflict management for urban regeneration project were based on limited case-studies on a specific phase. In addition, those studies did not considered a multidisciplinary approach for critical factor of conflict occurrence. In this reason, to establish a practical management or a policy is limited. In this paper, 'Good communication and information sharing' and 'Cooperativeness of stakeholders on project' are defined by critical factors for minimization of conflict between stakeholders. Furthermore we analysis the influence of those factors to minimization of conflict using path-analysis. This paper contributes to increase the efficiency of conflict management through understanding influence of each factors.

• 대한수학회논문집
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• 제11권3호
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• pp.841-853
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• 1996

This article finds smoothed perturbation analysis estimates for the derivatives of mean performance measures in a Markovian queue with batch arrivals. We show that those estimates can be observed from a single sample path.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2009년도 추계학술대회 논문집
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• pp.75-76
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• 2009

• 드라이브 ㆍ 컨트롤
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• 제13권1호
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• pp.72-77
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• 2016

• 한국유체기계학회 논문집
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• 제15권4호
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• pp.67-71
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• 2012

This study analyzed performance changes by an inner flow path of impeller groove for side channel type ring blower using CFD. Two models have the same side channel and clearance while one has an inner flow path and the other doesn't. To analyze the performance change of a ring blower, overall performance and local flow field were analyzed. For the overall performance, pressure increase and impeller torque were checked under the design flow condition. Under the design flow condition, pressure increase was greater for the model with the inner flow path. The model with the inner flow path showed improved efficiency because the area subject to torque decreased due to the creation of inner flow path. To analyze local flow field, a section was created from the representative location of each impeller groove toward the direction of radius. Inner channel pressure distribution depending on the rotation direction shows that the model with the inner flow path has pressure equilibrium of working fluid through the inner flow path. Velocity distribution of inside impeller groove shows that flow field was coupled and appeared to form an inner wall where the flow field was stabilized.

• 전기학회논문지
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• 제64권10호
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• pp.1479-1485
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• 2015

Robot's technology was very simple and repetitive in the past. Nowadays, robots are required to perform intelligent operation. So, path planning has been studied extensively to create a path from start position to the goal position. In this paper, potential field algorithm was used for path planning in dynamic environments. It is used for a path plan of mobile robot because it is elegant mathematical analysis and simplicity. However, there are some problems. The problems are collision risk, avoidance path, time attrition. In order to resolve path problems, we amalgamated potential field algorithm with the artificial neural network system. The input of the neural network system is set using relative velocity and location between the robot and the obstacle. The output of the neural network system is used for the weighting factor of the repulsive potential function. The potential field algorithm problem of mobile robot's path planning can be improved by using artificial neural network system. The suggested algorithm was verified by simulations in various dynamic environments.

• 한국전자거래학회지
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• 제17권4호
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• pp.39-56
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• 2012

최근의 RFID와 모바일 기술을 포함한 정보 기술의 진보로 인해 매장 내에서 고객 쇼핑 동선을 추적하는 것이 가능해지고 있다. 특히, 고객 쇼핑 동선은 매장 내에서 발생하는 고객 쇼핑 행동을 이해하는데 중요한 단서를 제공한다. 따라서 본 연구에서는 고객 동선 분석을 위하여 동선 정보를 획득하고 분석하는 고객 쇼핑 동선 분석 시스템을 개발한다. 시스템 개발을 위해 RFID를 사용하였고, 대형 유통 매장의 현업 전문가와 함께 다양한 매장 측정 변수를 정의하여 혼잡도, 방문비율등과 같은 매장 프로파일 분석과 고객 쇼핑 패턴 식별을 위해 동선 클러스터링 분석 기법을 개발하여 적용하였다. 최종적으로는 개발한 시스템의 실효성을 평가해보기 위하여 실제 서울의 대형 유통 매장에 적용하여 사례분석까지 실시해보았다.

• 한국소음진동공학회논문집
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• 제18권8호
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• pp.805-815
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• 2008

Transfer path analysis(TPA) and panel contribution analysis(PCA) have been used widely to reduce interior noise of mechanical systems. TPA enables us to decompose interior noise into air-borne and structure-borne noises and estimate the path contribution of noise sources. PCA is also used to identify the noise contribution of each sub-panel in vibro-acoustic systems. In this paper, TPA and PCA are applied to wheel loader, one of the heavy construction equipments. Firstly, TPA for air-borne noise is conducted to estimate the contribution of air-borne sources using pressure transfer function. Thereafter, TPA for structure -borne noise is employed to verify the results of air-borne source quantification through the synthesis of two results. Secondly, PCA is performed by both TPA using pressure transfer function between panels inside the cabin and boundry element method(BEM) for the cabin of wheel loader with various boundary conditions. As a results, it was found that TPA conducted by experiments and PCA accomplished by both experiments and BEM are very effective methods in analyzing the path and contribution of the noises for reducing an interior noise level in the wheel loader system.