• 제목/요약/키워드: Local Driving

검색결과 222건 처리시간 0.026초

TCMS와 ATC장치간 인터페이스 이중계 구현 및 무축제동 제어방안 (Design of redundancy interface between TCMS and ATC system, and brake control of free-axle system)

  • 홍구선;한신;한정수
    • 한국철도학회:학술대회논문집
    • /
    • 한국철도학회 2004년도 추계학술대회 논문집
    • /
    • pp.1461-1466
    • /
    • 2004
  • Recently Domestic EMU's on board signal systems are gradually changed form Cab signal(Fix Block) to Distance-to-go. Interfaces with on board signal system, TCMS Redundancy structure is mainly required. This paper suggest Manaul/Automatic Driving based on TCMS-ATC interface and design of backup system which is operated by Stan-by Computer when one of it's Local Interface Unit(LIU) is out of oder. For the purpose of Precision Train Stop, Distance-to-go signal system require accuracy speed. Free-axle structure is required for this system This paper suggest Free-axle braking system that lack of brake-force is compensated by the distributed brake-force using TCMS. And one of braking system has out of order, compensation of brake-force for Free-axle system. Then we prove our design to Complete Car Test

  • PDF

도로 주행 영상을 위한 안개 제거 기법 (Dehazing Algorithm for Road Driving Images)

  • 최광연;송병철
    • 한국방송∙미디어공학회:학술대회논문집
    • /
    • 한국방송∙미디어공학회 2016년도 추계학술대회
    • /
    • pp.169-171
    • /
    • 2016
  • 본 논문에서는 일반 자연 영상에서 주로 적용되어 왔던 안개 제거 기법을 기반으로 하여 악천후 상황의 도로 주행 영상을 개선하는 방법을 제안한다. 악천후 상황이란 안개가 있거나 비, 눈이 오는 상황을 의미한다. 도로를 주행하는 환경에서는 비나 눈이 오는 경우에도 안개가 있는 상황과 비슷하기 때문에 안개 제거 기법을 기반으로 하여 악천후 환경의 영상을 개선한다. 우선 최신의 안개 제거 기법 중 하나인 non-local prior 기반의 기법을 도로 주행 영상에 적용 하였을 경우 문제점이 발생하게 되는데 그에 대한 원인을 분석한다. 그리고 이러한 문제점을 해결하기 위하여 예상된 전달량을 보정한다. 모의 실험을 통해 제안하는 방법을 적용하여 도로 주행 영상에서 발생한 문제점을 완화하고 악천후 상황이 개선된 결과를 얻었다.

  • PDF

Unicycle-type 이동로봇의 비선형 제어 (Nonlinear control of unicycle-type mobile robot)

  • 김용진;문인혁
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 2001년도 하계종합학술대회 논문집(5)
    • /
    • pp.131-134
    • /
    • 2001
  • This paper proposes a stable control rule for nonlinear unicycle-type mobile robot. The control method uses a local error coordinate system, velocity and distance constants $\kappa$$\_$x/, $\kappa$$\_$y/, and he. Stability of control rule is proved Liapunov function. System input to the mobile robot is reference posture ($\chi$$\_$r/, y$\_$r/, $\theta$$\_$r/)/sup/ $\tau$/ and reference e velocity (ν$\_$r/,$\omega$$\_$r/)$\^$$\tau$/. System output of the mobi-le robot is velocity of driving wheels. We introduce limit velocity for preventing high initial speed. From simulation results, we can see the proposed control rule is stable.

  • PDF

고무 블록의 마찰 거동 해석 (Analysis of the Frictional Behavior of Rubber Block)

  • 김두만;유현승
    • 한국항공운항학회지
    • /
    • 제14권3호
    • /
    • pp.16-22
    • /
    • 2006
  • The friction and wear of tire determined by frictional behavior of tire tread that translate driving force, cornering force and braking force between automobile and road as a result of frictional behavior of each tread block. The tire tread block is representative case of rubber block doing frictional behavior. In this paper, frictional behavior of rubber block under compressive force and shear force was analytically obtained by using slip starting position parameter instead of friction coefficient which is uncertain to express exact value between rubber and other surfaces yet. And local coefficients of friction were calculated as a function of compressive force, shear force, shear modulus of rubber, shape factor and slip starting position.

  • PDF

궤도형 전투차량의 궤도박리 발생 및 성장모드 예측에 관한 연구 (Separation Mode Analysis of Track Assembly of Main Battle Tank)

  • 이경호;박병훈
    • 한국군사과학기술학회지
    • /
    • 제10권3호
    • /
    • pp.173-180
    • /
    • 2007
  • In this paper, we have proposed a simple finite element model for separation mode analysis on the roadwheel and track assembly of main battle tank and established a contact stress-based mechanism which could explain the initiation and growth of separation defect occurred during the test of padreplacable track. It was proved that the longitudinal contact shear stress component on the pin hole region of the track shoe body which is parallel to the driving direction is consistent with the crack initiation at the bonding surface between track shoe and wheel-side rubber. The longitudinal shear stress increased locally near the separated region after the separation initiated. So we could assume that the local stress concentration accelerates the separation growth according to the shear mode.

사이리스터의 결함과 항복전압의 관계 분석 (Analysis of the relationship between breakdown voltage and defect of thyristor)

  • 이양재;서길수;김형우;김기현;김상철;김남균;김병철
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
    • /
    • pp.149-150
    • /
    • 2005
  • Thyristor breakdown voltage variation acceleration aging test was investigated. The breakdown voltage was deceased after 1000 hours acceleration aging test. It temperature rising caused by electric field concentration at the edge beveling region of the thyristor was confirmed using Silvaco device simulation. The local temperature rising is driving force for the defect propagation. Consequently, propagated defects of the beveling region seems to decrease thyristor's breakdown voltage.

  • PDF

A Study of Mobile Edge Computing System Architecture for Connected Car Media Services on Highway

  • Lee, Sangyub;Lee, Jaekyu;Cho, Hyeonjoong
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • 제12권12호
    • /
    • pp.5669-5684
    • /
    • 2018
  • The new mobile edge network architecture has been required for an increasing amount of traffic, quality requirements, advanced driver assistance system for autonomous driving and new cloud computing demands on highway. This article proposes a hierarchical cloud computing architecture to enhance performance by using adaptive data load distribution for buses that play the role of edge computing server. A vehicular dynamic cloud is based on wireless architecture including Wireless Local Area Network and Long Term Evolution Advanced communication is used for data transmission between moving buses and cars. The main advantages of the proposed architecture include both a reduction of data loading for top layer cloud server and effective data distribution on traffic jam highway where moving vehicles require video on demand (VOD) services from server. Through the description of real environment based on NS-2 network simulation, we conducted experiments to validate the proposed new architecture. Moreover, we show the feasibility and effectiveness for the connected car media service on highway.

Altered synaptic connections and inhibitory network of the primary somatosensory cortex in chronic pain

  • Kim, Yoo Rim;Kim, Sang Jeong
    • The Korean Journal of Physiology and Pharmacology
    • /
    • 제26권2호
    • /
    • pp.69-75
    • /
    • 2022
  • Chronic pain is induced by tissue or nerve damage and is accompanied by pain hypersensitivity (i.e., allodynia and hyperalgesia). Previous studies using in vivo two-photon microscopy have shown functional and structural changes in the primary somatosensory (S1) cortex at the cellular and synaptic levels in inflammatory and neuropathic chronic pain. Furthermore, alterations in local cortical circuits were revealed during the development of chronic pain. In this review, we summarize recent findings regarding functional and structural plastic changes of the S1 cortex and alteration of the S1 inhibitory network in chronic pain. Finally, we discuss potential neuromodulators driving modified cortical circuits and suggest further studies to understand the cortical mechanisms that induce pain hypersensitivity.

무인비행체의 유사시 대안 경로 선택을 위한 DEVS 기반 디지털 트윈 시뮬레이션 환경 모델링 (DEVS-based Digital Twin Simulation Environment Modeling for Alternative Route Selection in Emergency Situations of Unnamed Aerial Vehicles)

  • 권보승;정상원;노영단;이종식;한영신
    • 한국멀티미디어학회논문지
    • /
    • 제25권8호
    • /
    • pp.1007-1021
    • /
    • 2022
  • Autonomous driving of unmanned aerial vehicles may have to pay expensive cost to create and switch new routes if unexpected obstacles exist or local map updates occured by the control system due to incorrect route information. Integrating digital twins into the path-following process requires more computing resources to quickly switch the wrong path to an alternative path, but it can quickly update the path during flight. In this study, we design a DEVS-based simulation environment which can modify optimized paths through short-term simulation of multi-virtual UAVs for applying digital twin concepts to path follow. Through simulation, we confirmed the possibility of increasing the mission stability of UAV.

33D LIDAR 를 기반으로 하는 저비용 자율 주행 시뮬레이터 프레임워크에 대한 연구 (Study about Low-Cost Autonomous Driving Simulator Framework Based on 3D LIDAR)

  • 오은택;조민우;구본우
    • 한국정보처리학회:학술대회논문집
    • /
    • 한국정보처리학회 2022년도 춘계학술발표대회
    • /
    • pp.702-704
    • /
    • 2022
  • 자율주행 시뮬레이터를 위한 대체재로 게임 엔진을 통한 가상 환경 모의 연구가 수행되고 있다. 하지만 게임 엔진에서는 자율 주행에 필요한 센서를 기기에 맞게 사용자가 직접 모델링을 해줘야 하기 때문에 개발 비용이 크게 작용된다. 특히, Ray 를 활용한 3D LIDAR 는 GPU(Graphics Processing Unit) 사용량이 많은 작업이기 때문에 저비용 시뮬레이터를 위해서는 저비용 3D LIDAR 모의가 필요하다. 본 논문에서는 낮은 컴퓨터 연산을 사용하는 C++ 기반 3D LIDAR 모의 프레임 워크를 제안한다. 제안된 3D LIDAR 는 다수의 언덕으로 이루어진 비포장 Map 에서 성능을 검증 하였으며, 성능 검증을 의해 본 논문에서 생성된 3D LIDAR 로 간단한 LPP(Local Path Planning) 생성 방법도 소개한다. 제안된 3D LIDAR 프레임 워크는 저비용 실시간 모의가 필요한 자율 주행 분야에 적극 활용되길 바란다.