랜덤워크를 이용한 생태네트워크 변화 모의예측방안 연구(Ⅱ)

김지영 ( Ji Young Kim ),노태호 ( Tae Ho Ro ),유상덕 ( Sang-duk Yoo ),서보용 ( Boyong Seo ) 한국환경정책평가연구원 2016 기본연구보고서 Vol.2016 No.-

어느 지역에 개발사업이 시행되면 이로 인해 자연상태에 인공적인 지형 장애요소들이 추가되고 이것들이 동물의 이동을 방해하여 사업 시행 전보다 이동 가능 통로가 감소해 동물들은 다른 이동경로를 선택하게 될 것이다. 이 연구는 개발사업이 생태계 네트워크에 미치는 영향을 예측하는 시뮬레이션 프로그램을 개발하고 이 프로그램을 이용하여 동물의 이동에 변화가 발생하는 것을 분석하는 방법을 제시한다. 이에 주어진 조건에서의 가능한 생태네트워크의 형성과 지형 장애요소가 추가되었을 때의 네트워크의 변화와 영향 정도를 모의 실험할 수 있는 Ecological Network Simulator(EN Simulator)를 개발하였다. EN Simulator의 분석조건을 설정하기 위한 초기 테스트(Background Test)와 이동선호 분석법(Basic Method)을 기본 방법으로 제시하였다. 이동선호 분석법은 동물이 어떤 한 지점에서 주변으로 이동할 때 가장 선호하리라 예상되는 방향을 랜덤워커의 이동 결과를 통해서 결정하는 방법으로, EN Simulator에서 사용하는 기본 분석방법이다. 이 기본 방법을 반복적으로 수행하면서 동물 이동을 모사해 동물의 이동가능성 변화를 공간적으로 분석하는 방법으로 주 이동방향 분석법(Major Movement Direction Analysis), 이동가능성 분석법(Permeability Analysis) 및 이동 추적법(Trekker)을 제시하였다. 시뮬레이션 결과와 실제 동물의 이동이 유사한지를 검토하기 위해서 EN Simulator에 의한 이동패턴과 고라니 이동 원격추적 결과 및 삵의 흔적 조사결과를 비교하였다. 시뮬레이션 결과와 실제 장애요소 간의 관계를 검토하기 위해 경사도에 따른 이동확률을 비교하였고 이를 토대로 최적의 이동확률을 설정하였다. 랜덤워커의 위치에 따라 시뮬레이션 결과에 얼마나 영향이 있을지를 검토하기 위해서 출발점에 따른 결과를 비교하여 제시하였고, 이를 Simulator에 반영하였다. EN Simulator를 이용하여 사업 시행 전과 사업 시행 후의 이동가능성이 어떻게 변하는지를 분석 제시하였다. 사업부지의 형태를 바꿀 경우 이동가능성에 발생되는 변화를 분석하였고 이를 이용하여 최적의 부지형태를 선정하기 위한 활용가능성을 제시하였다. EN Simulator의 사용방법을 정리한 매뉴얼은 부록에 수록하였다. As a development project is implemented in a certain area, addition of artificial obstacles may hider movements of animals, losing some available paths that they had been used without any interruptions. This kind of impacts results in that they find the other routes to pass around. This study is about developing simulation program for estimating impacts of development project on ecological network and analysing methods of change in animal movement paths are proposed. Ecological Network Simulator (EN Simulator) is developed to simulate possible ecological network changes and relative influences on the network when obstacles are added from disturbances by development project. Random walker is used as an imaginary animal in the EN Simulator and moves by choosing next position based on their probabilities. Each random walker determines its next position by probabilistic choice from adjacent points that have their own properties, which reflects existence of obstacles, inclination and surface condition. Suggested elementary methods are composed of `Background test` and `Basic method`. The Background test is to ensure the simulator works properly in a designated settings, and the Basic method is a fundamental operating method of the EN Simulator. In the Basic Method - analysis of moving preferences - the preferable direction is determined by analysing movement results of many random walkers starting from a point to other points located within a given distance. In addition, 3 spatial analysis methods - Major Movement Direction Analysis, Permeability Analysis and Trekker - are suggested to assess changes of movement patterns. These 3 assessment methods use iterations of the Basic method. Telemetry track records of water deer (Hydropotes inermis) and field traces of Leopart Cat (Prionailurus bengalensis euptilura) are used to validate the simulation results between imaginary movements of random walkers and real traces of animals. Various sets of probability values to define difficulties of movement due to inclination degree of geographical surfaces are applied to find an optimum setting parameters for EN Simulator. Results are compared to check stability of simulation results when starting points are selected by operators who may produce slight deviations inadvertently. Simulation analysis cases are presented to see change in moving probabilities before and after project implementation. Analyses are also accomplished to see changes in animal movement probabilities when shape of a site is modified. The results suggest that the simulator can be applied to find optimum site shape to minimize impacts on ecological networks. Manual is attached as an appendix.

17. 기본연구보고서 2015-17 : 랜덤워크를 이용한 생태네트워크 변화 -모의예측방안 연구(1)

김지영외,노태호,전동준,유상덕,서보용,신소이 한국환경정책평가연구원 2015 기본연구보고서 Vol.2015 No.-

이 연구는 개발 사업이 생태계 네트워크에 미치는 영향을 시뮬레이션하는 방법을 개발한것이다. 개발사업으로 인해 동물이동에 장애가 되는 지형장애물 요소가 증가하게 되면 동물의 이동 경로와 이동 가능성은 영향을 받게 된다. 이러한 영향을 모의실험하기 위해 생태네트워크의 변화를 예측할 수 있는 Ecological Network Simulator(EN Simulator)를 개발하였다. EN Simulator에서는 가상적인 동물의 이동을 모사하기 위해서 랜덤워크를 이용하였다. 각각의 랜덤워커는 인접한 각 방향으로의 장애물 존재 여부, 경사 난이도 그리고 바닥조건에 따른 통과확률을 고려하여 이동 용이성을 결정하고 이를 가중치로 반영한 랜덤 확률에 따라 이동 지점을 결정하여 이동한다. 각 지점에 주어지는 정보는 지형장애물 분석결과와 수계, 논, 밭, 도로 등의 분포, 고도 값 등의 지형정보와 개발계획의 경계 등에서 만들어진 것이다. EN Simulator의 활용을 위해서 초기 테스트(Background Test), 사업 전 테스트(Surface condition Test), 사업 후 테스트(Project Impact Test)로 나누어 테스트하도록 분석 방법을 구성하였다. 결과의 분석을 위해서 이동선호 분석법(Travelling Preference Analysis), 주 이동방향 분석법(Path Direction Analysis), 이동 가능성 분석법(Permeability Analysis), 이동 추적법(Path Tracing)을 제안하였다. 이동선호 분석법은 한 지점에서 주변 지역으로 주 이동 방향을 분석할 수 있는 방법으로 이 EN Simulator의 기본적인 작동 방법이다. 다른 세 가지 방법은 이동선호 분석법을 위치별 또는 경로를 추적하면서 반복 분석하는 방법이다. EN Simulator를 이용하여 사례 지역을 대상으로 사업으로 인한 생태네트워크의 변화를 모의 분석하였다. 분석 결과 동물이동 가능 경로들이 사업에 의해서 영향을 받는 지역과 그 정도를 모의 예측할 수 있었다. EN Simulator는 개발 사업으로 인해 동물의 이동 가능성이 어떻게 변화하는지를 정량화하여 예측할 수 있는 도구로 활용될 수 있으며 환경적 입지 적정성을 검토하는 데 활용 가능하다. Increase of geographical barriers due to construction projects possibly affects the pattern of moving paths and travelling probability of animals. To simulate this impact in a quantitative point of view, Ecological Network Simulator (EN Simulator) was developed to examine the changing pattern of ecological network caused by the establishing of development project (ex: artificial barrier such a building) in a certain area. Random Walk concept was a dopted and provided a core a lgorithm in developing EN Simulator that simulates animal movement. Each random walker decides their next position by calculating easiness of travelling within given data such as surface condition, elevation difference and existence of obstacles. The informations imposed on each location are resulted from geographical barrier mapping and geomorphic informations such as presence of water body, paddy area, cultivated field, various types of roads and boundaries of a new project site. In application methods, three different kinds of basic approaches are designed; a) Background Test (BT) for setting simulation conditions, b) Surface Condition Test (SVT) for assessing present state of ecological network and c) Project Impact Test (PIT) for assessing change of impacts by imposing a new development project plan. In simulation process, 4 different analyzing mechanism such as Travelling Preference Analysis (TPA), Path Direction Analysis (PDA), Permeability Analysis (PA) and Path Tracing (PT) can be applied under given conditions to examine impact of barrier on animal movement and ecological networks. Among these 4 analyses, the TPA that simulates the walkers`` movement from a starting point to a designated distance plays a framework for the other 3 analyses. The PDA is a tool that gives comprehensive movement patterns consisting of directions in each unit area. The results of PA show the effects of the permeability changes induced by a barrier on animals`` movement. Lastly, the PT can provide the information of the movement direction and path from a point to the other point in detail. The completeness and reliability of EN Simulator have been examined by applying two case studies with field survey. The simulation results successfully provide reliable information that explains how the artificial barrier developed by a project impacts on both ecological networks and animals`` movement. The analysis results also show detail changes in the area and paths that may be affected by addition of a certain project and are thought to be quite reasonably acceptable. In addition, the output of the EN Simulator can be evaluated as a objective and quantitative tool that possibly predicts the change of travelling probabilities of animal and assesses the degree of impact induced by new project in a certain area.

Validation of participant screening processes for simulator sickness management

Reed N.,Diels C.,Parkes A.M. 한국자동차공학회 2008 한국자동차공학회 Symposium Vol.2008 No.9

The incidence of simulator sickness impacts all simulators that purport to provide drivers with a realistic experience. It has symptoms similar to motion sickness but can occur in the absence of physical motion of the observer. TRL was commissioned by the Scottish Executive to train 700 professional commercial vehicle drivers on two full mission truck simulators. Monitoring the incidence and effects of simulator sickness were paramount to the success of the programme. The aim of the driver training was to improve driver safety and fuel efficiency. Drivers on the programme completed a short familiarisation drive before completing two sets of four exercises, spending about an hour in the simulator in total. The simulator recorded drivers’ fuel efficiency, gear changes, speed, and time taken. Drivers also completed questionnaires as part of the training programme, one of which was the simulator sickness questionnaire (SSQ) proposed by Kennedy, Lane, Berbaum, and Lilienthal (1993), completed before and after driving the simulator. This enabled drivers’ subjective feelings of sickness to be recorded. Drivers rated their experience in the simulator very highly and showed significant improvements in their driving performance. Driver age and previous experience of motion sickness were both correlated with reported sickness level. There was also a significant correlation between drivers’ attitudes to technology and their susceptibility to simulator sickness. The implications of these results for the development of screening processes to reduce the incidence of simulator sickness, consequences for the use of simulators for driver training, and the effectiveness of such a screening questionnaire on a small simulator training programme are discussed.

Bounded-wave EMP Simulator 안테나의 설계

선다영,최학근,임성빈,장재웅,김태윤,최근경 한국인터넷방송통신학회 2011 한국인터넷방송통신학회 논문지 Vol.11 No.5

근래에 EMP(electromagnetic pulse)의 위협이 증가하면서 이에 대한 방호 대책과 관련하여 전자파 보안 기술 개발의 필요성이 대두되고 있다. 그러나 해외에 비해 국내에서는 이에 관한 연구가 미진한 실정이다. 본 논문에서는 EMP에 대한 전자파 보안 기술 개발을 목적으로 EUT(equipment under test)의 EMP 내성을 시험할 수 있는 bounded-wave EMP simulator의 기본 형태인 평행판 simulator(parallel-plate simulator: PPS) 안테나를 설계하였다. 설계된 EMP simulator 안테나는 웨이브 런처, 전송 선로, 종단 테이퍼로 나누어 설계되었으며, 워킹 볼륨 내에서 가로, 세로, 높이가 30 cm 이내인 물체의 시험에 필요한 영역에 TEM 모드가 우세한 필드를 형성하여 EMP simulator로써 사용 가능할 것으로 보인다. A threat of the EMP(Electromagnetic Pulse) is recently increasing, so the development of electromagnetic security technology against the EMP is needed. However, the state of the domestic electromagnetic security technology against the EMP is lower level than the foreign. In this paper, the bounded-wave EMP simulator antenna for the development of electromagnetic security technology against a threat of the EMP is designed. The structure of the designed antenna is from a sort of the basic form of the bounded-wave EMP simulator such as a parallel-plate simulator for testing EMP immunity performance within the EUT(Equipment Under Test). The design processes of the designed simulator is including wave launcher, transmission line and termination taper. In the working volume of the designed antenna, the test object within 30 cm is forming predominant TEM field, so it is confirmed that the designed EMP simulator antenna can be used as the EMP simulator.

원격 훈련용 발전 시뮬레이터 개발

변승현,강해수,우주희,이지훈,김덕호,Byun, Seung-Hyun,Kang, Hae-su,Woo, Joo-Hee,Lee, Jee-Hoon,Kim, Duck-Ho 한국전력공사 2021 KEPCO Journal on electric power and energy Vol.7 No.2

Power plant simulators have been used for operator training, control verification and engineering verification. In general, simulators can be used in the place where they are installed by only single user group at a time. Considering high cost of simulator development, a lot of available scenarios, the diversity of user level and accessibility based on users' work location, development of simulator system that can be used by multiple user groups regardless of location is required in order to enhance utilization of simulators. In this paper, the simulator system that can be used by multiple user group simultaneously without location limitation is proposed. The simulator system is composed of simulator servers, database servers, HMI servers, a web server, web clients. Simulator server consists of control model, process model that are developed for Circulating Fluidized Bed power plant located overseas. A web server manages user accounts, operation procedures, multiple server access between web client group and simulator server group. In other words, a web server makes a user group select a simulator server at a time. The developed simulator system is integrated after implementing process model, control model, HMI, and web server. Web client systems are installed on local site where power plant is located, while simulator servers, HMI servers, database servers, and a web server are located in KEPCO RI. The developed simulator system is verified by steady-state test, malfunction test and so on via remote access.

Simulator를 이용한 인공무릎관절 접촉면의 압력분포 및 운동성 분석

이문규,김종민,김동민,최귀원 대한의용생체공학회 2003 의공학회지 Vol.24 No.4

인공무릎관절의 수명에 직접적인 영향을 주는 인자는 접촉면에 대한 접촉면적과 압력분포이다 따라서. 이에 대한 실험적인 평가가 필요하였고 knee simulator 혹은 K-scan sensor를 포함한 시스템과 같은 많은 연구가 진행되어 왔다. 그러나 지금까지 보행주기에 따른 연속적인 인공관절 운동에 대한 접촉면의 압력분포를 실시간으로 분석한 연구는 미흡하다 따라서 본 연구의 목적은 보행주기를 모사하는 simulator와 I-scan을 이용하여 연속적인 동작에 따른 접촉면의 압력분포를 분석함에 있다. 본 연구의 목적을 이루기 위해서 생체내 인공관절 환경을 정확히 표현할 수 있는 knee simulator를 제작하였다. 네 방향의 자유도를 갖고 있는 본 simulator는 soft tissue의 기능을 포함하고 있고 PC Program을 통하여 압축하중과 femoral component의 굴곡각을 조절할 수 있다. 본 시스템의 I-scan sensor는 보행주기에 따른 압력분포를 분석할 수 있다. 보행주기에 대한 압력분포는 압축하중곡선에 따라 주요하게 변화함을 알 수 있고 운동성에 영향을 쿠는 압력중심의 위치도 변한다는 것을 알 수 있다. 따라서 본 연구에서 제작한 knee simulator는 보행주기 같은 특정의 운동정보를 이용하여 접촉면의 압력분포 및 운동성 같은 기계적 성능을 평가할 수 있고 형상 설계를 위한 기초 자료를 제공할 수 있다. Contact area and pressure are important factors which directly influence a life of knee implants. Since implant's mechanical functions should be experimentally evaluated for clinical use, many studies using a knee simulator and a pressure sensor system have been conducted. However it has not been reported that the contact pressure's distribution of a knee implant motion was estimated in real-time during a gate cycle. Therefore. the objective of this study was to analyze the contact pressure distribution for the motion of a joint using the knee simulator and I-scan sensor system. For this purpose, we developed a force-controlled dynamic knee simulator to evaluate the mechanical performance of artificial knee joint. This simulator includes a function of a soft tissue and has a 4-degree-of-freedom to represent an axial compressive load and a flexion angle. As axial compressive force and a flexion angle of the femoral component can be controlled by PC program. The pressure is also measured from I-scan system and simulator to visualize the pressure distribution on the joint contact surfaces under loading condition during walking cycle. The compressive loading curve was the major cause for the contact pressure distribution and its center move in a cycle as to a flexion angie. In conclusion, this system can be used to evaluate to the geometric interaction of femoral and tibial design due to a measured mechanical function such as a contact pressure, contact area and a motion of a loading center.

무게-가변형 드론을 위한 동역학 기반 시뮬레이터 개발

백금봉,김정환,김식 대한임베디드공학회 2020 대한임베디드공학회논문지 Vol.15 No.3

Regarding previously-developed drone simulators, it was easy to check their flight stability or controlling functions based on the condition that their weight was fixed from the design. However, the drone is largely classified into two types that is the one with the fixed weight whose purpose is recording video with camera and racing and another is whole weight-variable during flight with loading the articles for delivery and spraying pesticide though the weight of airframe is fixed. The purpose of this thesis is to analyze the structure of drone and its flight principle, suggest dynamics-model-based simulator that is capable of simulating weight-variable drone and develop the simulator that can be used for designing main control board, motor and transmission along the application of weight-variable drone. Weight-variable simulator was developed by using various calculation to apply flying method of drone to the simulator. First, ground coordinate system and airframe-fixing coordinate system were established and switching matrix of those two coordinates were made. Then, dynamics model of drone was established using the law of Newton and moment balance principle. Dynamics model was established in Simulink platform and simulation experiment was carried out by changing the weight of drone. In order to evaluate the validity of developed weight-variable simulator, it was compared to the results of clean flight public simulator against existing weight-fixed drone. Lastly, simulation test was performed with the developed weight-variable simulation by changing the weight of drone. It was found out that dynamics model controlled various flying positions of drone well from simulation and the possibility of securing the optimum condition of weight-variable drone that has flying stability and easiness of controlling. Regarding previously-developed drone simulators, it was easy to check their flight stability or controlling functions based on the condition that their weight was fixed from the design. However, the drone is largely classified into two types that is the one with the fixed weight whose purpose is recording video with camera and racing and another is whole weight-variable during flight with loading the articles for delivery and spraying pesticide though the weight of airframe is fixed. The purpose of this thesis is to analyze the structure of drone and its flight principle, suggest dynamics-model-based simulator that is capable of simulating weight-variable drone and develop the simulator that can be used for designing main control board, motor and transmission along the application of weight-variable drone. Weight-variable simulator was developed by using various calculation to apply flying method of drone to the simulator. First, ground coordinate system and airframe-fixing coordinate system were established and switching matrix of those two coordinates were made. Then, dynamics model of drone was established using the law of Newton and moment balance principle. Dynamics model was established in Simulink platform and simulation experiment was carried out by changing the weight of drone. In order to evaluate the validity of developed weight-variable simulator, it was compared to the results of clean flight public simulator against existing weight-fixed drone. Lastly, simulation test was performed with the developed weight-variable simulation by changing the weight of drone. It was found out that dynamics model controlled various flying positions of drone well from simulation and the possibility of securing the optimum condition of weight-variable drone that has flying stability and easiness of controlling.

The Box Simulator Is Useful for Training Novice Endoscopists in Basic Endoscopic Techniques

차재명,이정일,주광로,신현필,박재준,전정원,임준욱,임규성 연세대학교의과대학 2012 Yonsei medical journal Vol.53 No.2

Purpose: The present study was aimed at evaluating the usefulness of box simulators for training novice endoscopists. Materials and Methods: An explanation of the goals, contents, and features of the simulator was given to study participants. The participants then received “hands-on training” in gastrointestinal endoscopy techniques using a box simulator. Subsequently, they were asked to answer 19 structured questions about the simulator. Ratings were scored on a scale from 1 to 5 for questions concerning their first impression of the simulator. Questions on the usefulness of the simulator and the training course were answered as “agree”, “disagree”,or “no opinion”. Results: A total of 32 participants filled out the questionnaire. The mean scores on the simulator’s usefulness, features, and realistic movements before the training were between 1.5 and 2.0. There were no significant differences between the mean values of the scores given by novice users compared to non-novice users. However, after receiving training on the simulator, 90.6% of the participants considered the box simulator a generally useful tool for learning basic endoscopic techniques, and 90.6% agreed that the simulator was useful for improving hand-eye coordination. Conclusion: Box simulators may be useful for training novice endoscopists in basic gastrointestinal endoscopic techniques.

Universal Power-Hardware-in-the-Loop Simulator for BLDCM and PMSM

Xu Jiaqun,Xing Meili,Zhang Hongqiang 한국자기학회 2019 Journal of Magnetics Vol.24 No.3

To improve the test efficiency and reduce the test cost, this paper presents a design method of universal power-hardware-in-the-loop (PHIL) simulator for brushless DC motor (BLDCM) and permanent magnet synchronous motor (PMSM). The actual stator winding is simulated by the power-level current source in the simulator, thus, the electric power can be interacted between the simulator and the motor driver. By the method of bilinear transform and inverse Z-transform, the line voltage based numerical models of the virtual motors are derived. Moreover, the relationship between the line voltage and phase current of the virtual motors is analyzed, which is used to calculate the phase current commands in the numerical models. Furthermore, the universal PHIL simulator is implemented and the real-time simulation is performed, and then the offline simulation with MATLAB software and the actual motor test are also performed to verify the simulator results. The simulation and experimental results show that both PMSM and BLDCM can be simulated accurately at the power level without changing any hardware of the motor driver and the simulator.

디지털 지형 고도 데이터를 이용한 자동 지형 추종 시뮬레이터 개발

이지수(Jisu Lee),유문규(MunGyou Yoo),이현주(Hyunju Lee),송기훈(Ki Hoon Song),전동익(Dong-Ik Cheon),이상철(Sangchul Lee) 항공우주시스템공학회 2024 항공우주시스템공학회지 Vol.18 No.1

In this paper, an Automatic Terrain Following (ATF) Simulator using Digital Terrain Elevation Data (DTED) was proposed. This ATF Simulator consists of a Flight Simulator, a Radar Simulator, and a Terrain Following Computer (TFC) Simulator. DTED and radar scan data generated with DTED were used as the terrain information necessary for terrain following. The ATF Simulator provides three modes of operation: a passive mode that uses DTED, an active mode that uses radar scan data, and a hybrid mode that uses both. We developed an ATF Simulator that could reduce the cost and time required to develop a terrain following system using the LabVIEW development environment and the MATLAB App Designer development environment. It was verified by confirming that the ATF Simulator met all functional requirements.