• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2001년도 하계종합학술대회 논문집(1)
• /
• pp.413-416
• /
• 2001

In high frequency range, RF circuit design without considering shielding effect can cause several significant changes due to increase in parasitic capacitance and inductance between RF signal lines and shielding box. In this paper, bandpass filter has been made to measure the shielding effect and its s-parameter has been measured by Vector Network Analyzer (VNA). Equivalent circuit model including the shielding effect has been constructed with the lumped elements extracted from the 3D electromagnetic simulator, Maxwell SI. Then, the validity of the model is verified using microwave circuit simulator, ADS (Advanced Design System).

• 제어로봇시스템학회논문지
• /
• 제10권4호
• /
• pp.371-376
• /
• 2004

Distributed Network Protocol Version 3.0 (DNP3.0) is the communication protocol developed for the interoperability between a RTU and a central control station of SCADA in the power utility industry. In this paper DNP3.0 is implemented by using HDL with FPGA and C program on Hitachi H8/532 processor. DNP3.0 is implemented from physical layer to network layer in hardware level to reduce the computing load on a CPU. Finally, the ASIC for DNP3.0 has been manufactured from Hynix Semiconductor. The commercial feasibility of the hardware through the communication test with ASE2000 and DNP Master Simulator is performed. The developed protocol becomes one of IP, and can be used to implement SoC for the terminal device in SCADA systems. Also, the result can be applicable to various industrial controllers because it is implemented in HDL.

• 상하수도학회지
• /
• 제29권3호
• /
• pp.427-436
• /
• 2015

Developing two process models to simulate wastewater treatment process is needed to draw a comparison between measured BOD data and estimated process model data: a mathematical model based on the process mass-balance and an ANN (artificial neural network) model. Those two types of simulator can fit well in terms of effluent BOD data, which models are formulated based on the distinctive five parameters: influent flow rate, effluent flow rate, influent BOD concentration, biomass concentration, and returned sludge percentage. The structuralized mass-balance model and ANN modeI with seasonal periods can estimate data set more precisely, and changing optimization algorithm for the penalty could be a useful option to tune up the process behavior estimations. An complex model such as ANN model coupled with mass-balance equation will be required to simulate process dynamics more accurately.

• 한국전자통신학회논문지
• /
• 제13권6호
• /
• pp.1223-1228
• /
• 2018

고속철도 시스템에서 열차의 안전 운행을 지원하기 위해서 사용되는 이동통신기술로서 LTE-R(: Long Term Evolution-Railway)은 열차의 고속이동환경에 적합한 핸드오버기술을 갖추어야 한다. 본 논문에서는 철도통신시스템에서 사용되는 LTE-R 네트워크의 핸드오버 성능을 분석하고 이를 토대로 핸드오버 수행 조건을 제시한다. 성능 분석은 NS(: Network Simulator)-3를 기반으로 하는 컴퓨터 시뮬레이션을 사용하며 성능 파라미터로는 SINR(: Signal to Interference and Noise Ratio), RSRP(: Reference Signal Received Power) 및 데이터율을 사용한다.

• 한국전자통신학회논문지
• /
• 제15권6호
• /
• pp.1017-1022
• /
• 2020

LTE-R(: Long Term Evolution-Railway)은 고속열차시스템 운영을 위한 필수 기술로서 LTE를 기반으로 한다. 고속열차 이동속도는 상용인 400[㎞/h] 급을 넘어 최근에는 600[km/h] 급으로 향하고 있다. 고속열차 시스템 통신기술로서 LTE-R은 열차의 이동속도에 적합한 끊김없는 통신을 제공해야 한다. 본 논문에서는 이를 위한 LTE-R 핸드오버 기술로서 예측기반 핸드오버를 제시하고 그 성능을 분석한다. 본 논문은 NS(:Network SImulator)-3에 기반한 컴퓨터 시뮬레이션을 사용하여 수행한다.

• 전기학회논문지P
• /
• 제58권3호
• /
• pp.263-269
• /
• 2009

This paper describes comparative analysis results about the dynamic interaction of interconnected wind power system using the actual-size hardware simulator and the simulation model with PSCAD/EMTDC. The hardware simulator, which is composed of 2.0MVA induction motor with drive system and 1.5MW doubly-fed induction generator, was built and tested in Go-Chang Test Site of KEPCO for analyzing the dynamic interaction with the interconnected distribution system. The operation of hardware simulator was verified through comparative analysis between experimental results and simulation results obtained by simulation model with PSCAD/EMTDC. The developed hardware simulator and simulation model could be effectively used for analyzing the dynamic interaction, which has various phenomena depending on the wind variation and the network state of interconnected power system.

• KIEE International Transactions on Power Engineering
• /
• 제3A권2호
• /
• pp.93-99
• /
• 2003

This paper deals with the development and testing of a large-scale, realtime digital power system simulator for the Korean Electric Power Corporation. The KEPS Simulation Center is located at KEPCO's research center (KEPRI) in Taejon, South Korea and has been operated since September 2001. The KEPS Simulation Center includes a wide range of off line power system simulation and analysis tools, as well as an advanced realtime digital simulator for the study of large scale AC and DC system performance. Because the application scope of the KEPS realtime simulator is broad and because the network models being considered are significantly larger and more complex than in traditional realtime simulator applications, many developments and tests have been required during the course of the project. In this paper, the authors describe some of these developments and present results from various benchmark tests that have been performed.

• Fisheries and Aquatic Sciences
• /
• 제7권3호
• /
• pp.163-170
• /
• 2004

A fishing simulator for towed fishing gear was investigated in order to mimic the fish behavior in capture process and investigate fishing selectivity. A fish behavior model using a psycho-hydraulic wheel activated by stimuli is established to introduce Lorenz chaos equations and a neural network system and to generate the components of realistic fish capture processes. The fish positions within the specified gear geometry are calculated from normalized intensities of the stimuli of the fishing gear components or neighboring fish and then these are related to the sensitivities and the abilities of the fish. This study is applied to four different towed gears i.e. a bottom trawl, a midwater trawl, a two-boat seine, and an anchovy boat seine and for 17 fish species as mainly caught. The Alpha cluster computer system and Fortran MPI (Message-Passing Interface) parallel programming were used for rapid calculation and mass data processing in this chaotic behavior model. The results of the simulation can be represented as animation of fish movements in relation to fishing gear using Open-GL and C graphic programming and catch data as well as selectivity analysis. The results of this simulator mimicked closely the field studies of the same gears and can therefore be used in further study of fishing gear design, predicting selectivity and indoor training systems.

• Journal of Advanced Research in Ocean Engineering
• /
• 제3권3호
• /
• pp.136-148
• /
• 2017

The paper presents dual arm ROV manipulation using deep reinforcement learning. The purpose of this underwater manipulator is to investigate and excavate natural resources in ocean, finding lost aircraft blackboxes and for performing other extremely dangerous tasks without endangering humans. This research work emphasizes on a self-learning approach using Deep Reinforcement Learning (DRL). DRL technique allows ROV to learn the policy of performing manipulation task directly, from raw image data. Our proposed architecture maps the visual inputs (images) to control actions (output) and get reward after each action, which allows an agent to learn manipulation skill through trial and error method. We have trained our network in simulation. The raw images and rewards are directly provided by our simple Lua simulator. Our simulator achieve accuracy by considering underwater dynamic environmental conditions. Major goal of this research is to provide a smart self-learning way to achieve manipulation in highly dynamic underwater environment. The results showed that a dual robotic arm trained for a 3DOF movement successfully achieved target reaching task in a 2D space by considering real environmental factor.

• 전자공학회논문지A
• /
• 제33A권6호
• /
• pp.206-219
• /
• 1996

This paper describes a data structure and evaluation algorithm to improve the perofmrances MOS logic-with-timing simulation in computation and accuracy. In order to efficiently simulate the logic and timing of driver-load networks, (1) a tree data structure to represent the mutual interconnection topology of switches and nodes in the driver-lod network, and (2) an algebraic modeling to efficiently deal with the new represetnation, (3) an evaluation algorithm to compute the linear resistive and capacitive behavior with the new modeling of driver-load networks are developed. The higher modeling presented here supports the structural and functional compatibility with the linear switch-level to simulate the logic-with-timing of digital MOS circuits at a mixed-level. This research attempts to integrate the new approach into the existing simulator RSIM, which yield a mixed-klevel logic-with-timing simulator MIXIM. The experimental results show that (1) MIXIM is a far superior to RSIM in computation speed and timing accuracy; and notably (2) th etiming simulation for driver-load netowrks produces the accuracy ranged within 17% with respect ot the analog simulator SPICE.