• 한국통신학회:학술대회논문집
• /
• 한국통신학회 1990년도 추계종합학술발표회논문집
• /
• pp.164-168
• /
• 1990

• 한국통신학회:학술대회논문집
• /
• 한국통신학회 2006년도 하계종합학술발표회 논문 초록집
• /
• pp.513-513
• /
• 2006

• International Journal of Fuzzy Logic and Intelligent Systems
• /
• 제11권1호
• /
• pp.49-53
• /
• 2011

Path following of the mobile robot is one research hot for the mobile robot navigation. For the control system of the wheeled mobile robot(WMR) being in nonhonolomic system and the complex relations among the control parameters, it is difficult to solve the problem based on traditional mathematics model. In this paper, we presents a simple and effective way of implementing an adaptive following controller based on the PID for mobile robot path following. The method uses a non-linear model of mobile robot kinematics and thus allows an accurate prediction of the future trajectories. The proposed controller has a parallel structure that consists of PID controller with a fixed gain. The control law is constructed on the basis of Lyapunov stability theory. Computer simulation for a differentially driven nonholonomic mobile robot is carried out in the velocity and orientation tracking control of the nonholonomic WMR. The simulation results of wheel type mobile robot platform are given to show the effectiveness of the proposed algorithm.

• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 2000년도 추계학술대회 논문집
• /
• pp.109-112
• /
• 2000

This paper presents an analytical study that can predict the path-dependent forming limits for bilinear strain paths. To predict the forming limit diagrams(FLD), the analytical procedure was performed within the framework of Marciniak and Kuczynski approach by introducing the effect of the existence of strain gradient over the stretching punch. The predicted path-dependent forming limits of an anisotropic sheet were compared with the published experimental results. It was found that the predicted path-dependent forming limits were in good agreement with the experimental data.

• 한국소음진동공학회논문집
• /
• 제25권6호
• /
• pp.426-431
• /
• 2015

In this work, a new type of MR damper with additional flow path in piston is proposed and damping force characteristics are numerically evaluated. Flow-mode type MR damper is considered and mathematical model is established based on Bingham rheological model of MR fluid to obtain accurate prediction of damping force characteristics. Damping force of the proposed MR damper are calculated with respect to piston velocity and input current. In addition, investigation on damping force characteristics is carried out according to number of additional flow path and excellence of the proposed MR damper is demonstrated.

• 한국자동차공학회논문집
• /
• 제4권3호
• /
• pp.112-121
• /
• 1996

Applications of bonded dissimilar materials such as metal/ceramics and resin/metal joints, are very increasing in various industry fields. It is required to find crack propagation direction and path applying to the fracture mechanics on the bonded joint of dissimilar meterials. In this paper, crack propagation direction and path were simulated numerically by using boundary element method. Crack propagation angle is able to easily determine based on the maximum stress concept. Fracture tests of Al/Epoxy dissimilar materials with an interface crack are carried out under various mixed mode conditions by using the specimens of bonded scarf joints. It is found that the experimental results are well coincide with the analysis results of boundary element method.

• Geomechanics and Engineering
• /
• 제13권5호
• /
• pp.743-756
• /
• 2017

Laboratory investigation reveals that rockfills exhibit significant stress-path-dependent behavior during shearing, therefore realistic prediction of deformation of rockfill structures requires suitable constitutive models to properly reproduce such behavior. This paper evaluates the capability of a strain hardening model proposed by the authors, by comparing simulation results with large-scale triaxial stress-path test results. Despite of its simplicity, the model can simulate essential aspects of the shear behavior of rockfills, including the non-linear stress-strain relationship, the stress-dependence of the stiffness, the non-linear strength behavior, and the shearing contraction and dilatancy. More importantly, the model is shown to predict the markedly different stress-strain and volumetric behavior along various loading paths with fair accuracy. All parameters required for the model can be derived entirely from the results of conventional large triaxial tests with constant confining pressures.

• 융합정보논문지
• /
• 제11권2호
• /
• pp.82-89
• /
• 2021

본 연구의 목적은 투자자의 은퇴 시점뿐만 아니라 시장의 예측 변동성을 동시에 고려하여 Target Date Fund의 위험자산 편입 비율을 동적으로 조정하는 새로운 Glide Path를 제안하고, 은퇴 시점만 고려하여 위험자산 편입 비율이 정해지는 전통적 Glide Path와 투자 성과를 비교 분석하는 것이다. 시장 변동성의 예측치로는 역사적 변동성, 시계열모형인 GARCH 변동성, 그리고 변동성지수인 VKOSPI를 활용하였으며, 2003년부터 2020년까지의 분석 기간에서 변동성을 고려하는 새로운 동적 Glide Path의 투자 성과가 우수함을 보여주었다. 3가지 변동성 예측모형 모두에서 은퇴 시점만을 고려하는 Glide Path보다 수익률은 더 높고 위험은 더 낮아지면서 투자 성과 지표인 Sharpe Ratio가 개선되었다. 실증 분석 결과는 은퇴예정자뿐만 아니라 Target Date Fund 운용업계에 새로운 Glide Path의 활용 가능성을 제시하고 있다.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 1998년도 하계종합학술대회논문집
• /
• pp.169-172
• /
• 1998

A 3D-ray tracing using triangular ray tubes for predicting propagation in indoor environments is presented. Employed ray tracing scheme needs no reception sphere often suffered from how to assign the correct radius as a touching ray on the receiver. To verify the developed codes path loss for a rectangular corridor has been computed, measured, and compared with those by image methods, all shows good agreement to each other. Discussions are made on the path loss fluctuations along the distance in a rectangular corridor having a conducting knife.

• 정보과학회 논문지
• /
• 제42권2호
• /
• pp.255-263
• /
• 2015

센서 레지스트리 시스템은 이기종 센서 네트워크 환경에서 센서 데이터의 즉시적 활용 및 끊김 없는 해석을 위해 개발되었다. 그러나 기존 센서 레지스트리 시스템은 불안정한 네트워크 상황에서 센서 데이터 해석을 위한 정보를 제공하지 못하며, 이로 인해 센서 데이터의 손실, 처리 결과의 부정확성, 서비스 품질 저하 등의 문제를 야기한다. 이 논문에서는 소프트웨어 관점에서 이러한 문제점을 해결할 수 있는 방안을 제시한다. 사용자의 이동 경로를 예측하여 사전에 센서 정보를 이동 단말기에 제공함으로써 불완전한 네트워크 접속 시점에 안정적으로 센서 정보를 활용할 수 있는 확장된 센서 레지스트리 시스템을 제안하고 실험 및 평가 결과를 보인다. 이 논문에서 제안한 확장된 센서 레지스트리 시스템은 센서 정보의 안정적 활용성 증가와 더불어 센서 기반 서비스 품질을 향상시킨다.