• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.130-131
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• 2007

본 논문에서는 자기포화특성이 두드러진 매입형 영구자석 동기전동기의 특성해석, 설계 및 제어에 응용할 수 있는 통합변수인 d-q축 쇄교자속(Flux Linkage)의 추출에 대하여 나타낸다. 특히, 영구자석과 전기자전류에 의한 Cross-Magnetization을 고려한 특성을 유한요소법(F.E.M)을 통하여 나타내며, 제작된 시작기 실험을 통하여 제안된 추출기법의 타당성을 나타낸다.

• Journal of Korean Society for Quality Management
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• v.21 no.1
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• pp.181-189
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• 1993

Over the past two decades, forecasting has gained widespread acceptance as an integral part of business planning and decision making. Accurate forecasting is a prerequisite to successful planning. Accordingly, recent advances in forecasting techniques are of exceptional value to corporate planners. But most of forecasting mothods are reveal its limit and problem for precision and reliability duing to each relationship for raw data and possibility of explanation for each variable. Therefore, to construct the Integrated Forecasting Model(IFM) for Information Factor Analysis, it shoud be considered that whether law data has time lag and variables are explained. For this. following several method can be used : Least Square Method, Markov Process, Fibonacci series, Auto-Correlation, Cross-Correlation, Serial Correlation and Random Walk Theory. Thus, the unified property of these several functions scales the safety and growth of the system which may be varied time-to-time.

• Journal of Korea Water Resources Association
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• v.52 no.10
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• pp.719-728
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• 2019

Valve in water distribution network (WDN), that controls the flow in pipes, is used to isolate a segment (a part of WDN) under abnormal water supply conditions (e.g., pipe breakage, water quality failure event). The segment isolation degrades pressure and water serviceability in neighboring area during the water service outage of the segment. Recent hydraulic and water quality failure events reported encouraging WDN valve installation based on various abnormal water supply scenarios. This study introduces a scenario-based optimal valve installation approach to optimize the number of valves, the amount of undelivered water, and a shortest water supply path indicator (i.e., Hydraulic Geodesic Index). The proposed approach is demonstrated in the valve installation of Pescara network, and the optimal valve sets are obtained under multiple scenarios and compared to the existing valve set. Pressure-driven analysis (PDA) scheme is used for a network hydraulic simulation. The optimal valve set derived from the proposed method has 19 fewer valves than the existing valve set in the network and the amount of undelivered water was also lower for the optimal valve set. Reducing the reservoir head requires a greater number of valves to achieve the similar functionality of the WDN with the optimal valve set of the original reservoir head. This study also compared the results of demand-driven analysis (DDA) and the PDA and confirmed that the latter is required for optimal valve installation.

• Journal of the Korean Institute of Telematics and Electronics T
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• v.36T no.3
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• pp.94-100
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• 1999

In this paper, we are implemented the courseware targets to the integrated a digital system analysis, a design theory, and a hardware description language training and a logic analysis. This paper consists of two subjects. One is that the learning of a digital system analysis, that of a design theory, and the training of a hardware description language is simultaneously performed. The other is that the experiment of courseware. To learn the hardware description language, the explanation using sound or moving images, setting-up of a simulation or a synthesis program, and simulating are executed on a courseware. And also, we proposed an integrated systems for the hardware description language and a logic synthesis. Also, The reliablity of the tool was verified to be preyed an efficient operation of an implemented digital system courseware tool by korea computer research association.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.11
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• pp.1423-1428
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• 2011

This paper proposes a learning input shaper with nonlinear actuator dynamics to reduce the residual vibration of flexible systems. The controller is composed of an estimator of the time constant of the nonlinear actuator dynamics, a recursive least squares method, and an iterative updating algorithm. The updating mechanism is modified by introducing a vibration measurement function to cope with the dynamics of nonlinear actuators. The controller is numerically evaluated with respect to parameter convergence and control performance by using a benchmark pendulum system. The feasibility and applicability of the controller are demonstrated by comparing its control performance to that of an existing controller algorithm.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1320-1325
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• 2008

In the manufacture of automobile suspension modules at a company as parts supplier, the design process includes the detail design and the design modification via structural and fatigue durability analyses considering PoF(physics of failure) of their weldments that are repeated more than four times sequentially. The approval of the design and the release of final drawings follows. For the suspension modules, e.g. control arms and cross member, the man-hours per worker required in the process outlined above can reach as high as 1,414hours. Application of the developed integrated design system can reduce the man-hours of 1,004. In comparison with the conventional design process, this integrated design system reduces the required time by about 40%. If expense is taken into account, a savings of approximately $192,000 is estimated, assuming the design process accounts for 1.5% of total sales for the parts supplier

• Proceedings of the Korea Information Processing Society Conference
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• 2021.11a
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• pp.19-22
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• 2021

본 논문은 군과 경찰 등에서 수행하는 시뮬레이션 사격 훈련 중 스크린 사격과 VR 사격이 혼합된 복합 훈련 환경에서 사용할 수 있는 일체형 시뮬레이션 사격 서비스에 대해 연구하였다. 이 서비스는 스크린과 HMD에 투사되는 목표물에 대해 사격 훈련이 가능하도록 설계한 서비스로 하나의 가상공간에서 사용할 경우 스크린을 이용한 개인 사격 훈련과 VR을 이용한 팀 사격 훈련이 동시에 가능하다. 일체형 시뮬레이션 총기의 총구에 비가시 적외선 레이저 모듈을 장착하여 스크린 사격이 가능하도록 하고, 총열 상단에 HTC Vive Tracker를 장착하여 VR 사격에서 훈련자의 자세 및 위치를 인식하게 한다. 총열 하단에는 사용자의 행동을 제어하는 손잡이 형태의 인터페이스 모듈을 장착한다. 비가시 적외선 레이저 모듈과 인터페이스 모듈에서 발생한 신호는 일체형 시뮬레이션 총기의 총열에 장착한 무선 통신 모듈에 의해 블루투스 방식으로 통합 제어 장치로 전달되어 처리함으로써 혼합 환경에서 사용이 가능하다. 스크린 사격과 VR 사격이 동시에 가능한 혼합 환경에서 시험한 결과 운용이 가능한 것을 확인하였다. 일체형 시뮬레이션 사격 서비스는 기존 사람 중심의 훈련 서비스에서 자동차 또는 함정 등과 같은 조종 훈련 플랫폼과 연동하여 운용할 수 있는 기술 발전이 필요하다.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.2
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• pp.361-368
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• 2019

This paper is a study on integrated air-conditioning system for 1-ton class commercial vehicle based on electric vehicle. In the case of an electric commercial vehicle, since the opening and closing of the door is frequently performed in order to get in and out of the cargo, the heat loss largely occurs. Therefore, the heating and cooling load is required to be larger than the electric vehicle. As a result, the energy consumed by the heating and cooling system is larger than the passenger electric car in order to satisfy the heat comfort required by passengers. In order to overcome these disadvantages, we performed research using an efficient integrated air conditioning system. Finally, the design and analysis of a heat pump system for heating and a electrical compressor for cooling need to be proceed to develop a high-efficiency air conditioning system for improving the commerciality of 1 ton-class electric trucks and expanding the industrial ecosystem in the electric truck sector.

• Journal of the Korean Institute of Gas
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• v.17 no.2
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• pp.78-84
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• 2013

A numerical study on the heat and fluid flow has carried out for the design of the steam reforming reactor which consists of six reforming tubes and one burner. Reforming reaction calculation is coupled with the heat and fluid flow one. The burner type in the reforming reactor is chosen through the fluid flow calculation according to different type of burner structure. It is shown that the significant temperature gradient exists in the reforming reactor, affecting the component variation along the length of reforming tube. The component ratio of reforming gas is changed by the variation of SCR and GHSV.

• Journal of the Korean GEO-environmental Society
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• v.18 no.8
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• pp.5-15
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• 2017

To perform an integrated load analysis carried out to evaluate the stability evaluation of wind turbine generators, the six degree-of-freedom stiffness matrix of foundation, which describes relationships between loads and displacement, is needed. Since the foundation stiffness should accurately reflect the shape of foundation and the condition of soil, it is necessary to calculate the stiffness of the bucket foundation that considers the elasto-plastic behavior of the soil. In this study, finite element analyses were performed for a range of soils and shapes of bucket foundations to estimate the foundation stiffness. Normalized stiffness curves are developed from respective numerical simulations. Proposed results are considered to be useful because they can be directly applied in the design.