• Title/Summary/Keyword: Vehicle pulse

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A Novel Timing Control Method for Airborne SAR Motion Compensation (항공기 요동보상을 위한 SAR시스템의 타이밍 제어 기법)

  • Lee, Hyon-Ik
    • Journal of the Korea Institute of Military Science and Technology
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    • v.13 no.3
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    • pp.453-460
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    • 2010
  • For high quality image acquisition, compensating air-vehicle motion is essential for airborne SAR system. This paper describes a timing control based motion compensation method for airborne SAR system. Efficient timing control is critical for SAR system since it maintains many timing signals and timing setting for the signals should be updated frequently. This paper proposes Timing Cluster method as an efficient means for timing control of SAR system. Moreover, this paper suggests a simple and efficient method to compensate air-vehicle motion based on the Timing Cluster method. Timing Cluster method enables SAR system to control the timing in a timing noncritical way just maintaining little amount of information.

Development of Vector Controlled Traction System (벡터제어를 이용한 전동차 구동 시스템)

  • 배본호;설승기;김상훈;이일호;한성수
    • Proceedings of the KSR Conference
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    • 1999.11a
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    • pp.288-295
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    • 1999
  • This paper presents an application of vector control strategy for 1.2MVA IGBT traction drive for electric railway vehicle. The vector control requires the control of the phase and amplitude of output voltage vector[5]. But in case of traction system far railway vehicle, the one-pulse mode is used in order to utilize the link voltage fully[8]. So it is impossible to control the flux axis current and the torque axis current instantaneously and independently. So this paper proposes the vector control strategy with slip-frequency control at one-pulse mode. And precise switching technique between the two different control structures has been proposed. And the strategy was verified by experimental result with 1.2MVA IGBT inverter with four 210㎾ induction motors.

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Development of propulsion system for the Urban Transit Maglev System (도시형 자기부상열차 적용을 위한 추진제어장치의 개발)

  • 이은규;송영신;최재호
    • Proceedings of the KSR Conference
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    • 2002.10a
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    • pp.440-445
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    • 2002
  • In this paper, traction system for urban transit maglev system is proposed. Using vector control strategy to control magnitude and frequency of output voltage transiently is general. But in case of traction system for railway vehicle, it is impossible that adapt vector control because there is one-pulse mode in a high speed region. So this paper proposes the control strategy using vector control in a low speed region and slip frequency control in a high speed region. And also proposes overmodulation method that makes to change in one-pulse mode softly. The performance of traction system will be verified by simulation results using ACSL.

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A Study on Improvement of Crash Discrimination Performance for Offset and Angular Crash Events Using Electronic X-Y 2-Axis Accelerometer (전자식 X-Y 이축 가속도 센서를 이용한 오프셋 및 경사 충돌에 대한 충돌 판별 성능 개선에 관한 연구)

  • 박서욱;전만철
    • Transactions of the Korean Society of Automotive Engineers
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    • v.11 no.1
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    • pp.128-136
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    • 2003
  • In today's design trend of vehicle structure, crush zone is fiequently reinforced by adding a box-shaped sub-frame in order to avoid an excessive deformation against a high-speed offset barrier such as EU Directive 96/97 EC, IIHS offset test. That kind of vehicle structure design results in a relatively monotonic crash pulse for airbag ECU(Electronic Control Unit) located at non-crush zone. As for an angular crash event, the measured crash signal using a single-axis accelerometer in a longitudinal direction is usually weaker than that of frontal barrier crash. Therefore, it is not so easy task to achieve a satisfactory crash discrimination performance for offset and angular crash events. In this paper, we introduce a new crash discrimination algorithm using an electronic X-Y 2-axis accelerometer in order to improve crash discrimination performance especially for those crash events. The proposed method uses a crash signal in lateral direction(Y-axis) as well as in longitudinal direction(X-axis). A crash severity measure obtained from Y-axis acceleration is used to improve the discrimination between fire and no-fire events. The result obtained by the proposed measure is logically ORed with an existing algorithm block using X-axis crash signal. Simulation and pulse injection test have been conducted to verify the performance of proposed algorithm by using real crash data of a 2,000cc passenger vehicle.

Damage Classification by Time Density Function of Ultrasonic Pulse Signal occurred at Tire (타이어에서 발생하는 초음파펄스신호의 시간밀도함수에 의한 손상 분별)

  • Kang, Dae-Soo
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.15 no.6
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    • pp.291-296
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    • 2015
  • The tire damage classification method is researched on the periodicity detection of ramdomness ultrasonic signals to occur at the driving vehicle tire. Setting method of adaptive threshold is proposed in order to valid pulse detection by tire damage in ultrasonic noise on the road and used low pass filter for decrease signal ramdomness as preprocessing. Time interval of detected pulse is setted the density function depend on the vehicle's speed and the method of tire damage detection is proposed that measuring the first peak's time of time density function.The result of time density function in case of one damage material, the first peak's time is measured within the error limit of tire's rotation period, 169.8ms and 97.9ms and 81.8ms, about the speed of 50km/h and 80km/h and 100km/h. In case of more than one damage material, the sum of each peak's time is measured within the error limit of tire's rotation period about the speed.

Pulse-to-Pulse Coding for Channel Interference Suppression of Short Range Radar for GVES (지상 기동 장비용 근거리 레이더의 채널 간섭 억제를 위한 펄스간 코딩 연구)

  • Park, Gyu-Churl;Ha, Jong-Soo
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.20 no.9
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    • pp.883-889
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    • 2009
  • Since the SRRs(Short Range Radar) load on the GVESs(Ground Vehicle Equipment System) are operated within several hundred meters, it is important to suppress the interferences between the SRRs. These interference are reduced using the frequency separation between channels, however this method isn't a perfect solution owing to a difficulty of a realization for the interference suppression. Thus, a pulse-to-pulse coding used to suppress the interference fundamentally is proposed in this paper. The concept, the application method and the test results of the proposed method have been described in this paper.

A Music Recommendation System for a Driver in Vehicle (운전자 맞춤형 음악제공 시스템)

  • Choi, Goon-Ho;Kim, Yoon-Sang
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.58 no.7
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    • pp.1435-1442
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    • 2009
  • This paper proposes a music recommendation system for a driver in vehicle. The proposed system provides (selects and plays) a music to a driver in vehicle in real-time manner by inferring his preference based on physical, environmental, and personal information. Pulse data as physical information, age and biorhythm as personal information, and time as environmental information are used to infer a driver's and thus recommend a music. Experimental results showed that the proposed system could provide better satisfaction to a driver on the recommended music compared to the conventional approach.

Robust Wheel Slip Controller for Vehicle Stability Control

  • Kwak, Byung-Hak;Park, Young-Jin
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.174.4-174
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    • 2001
  • Vehicle stability control system can enhance the vehicle stability and handling in the emergency situations through the control of traction and braking forces at the individual wheels. To achieve the desired performance, the wheel slip controller manages the hydraulic braking system to generate the desired braking force at each wheel. In this study, we propose the wheel slip controller for the generation of the braking forces based on multiple sliding mode control theory with the pulse width modulation. The proposed controller follows to the slip ratio and the brake pressure the desired ones so that the vehicle stability controller can Intervene braking force at each wheel. We show the validity and usefulness of the proposed controller through computer simulations.

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FRONTAL IMPACT FINITE ELEMENT MODELING TO DEVELOP FRP ENERGY ABSORBING POLE STRUCTURE

  • Elmarakbi, A.M.;Sennah, K.M.
    • International Journal of Automotive Technology
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    • v.7 no.5
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    • pp.555-564
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    • 2006
  • The aim of this paper is to contribute to the efficient design of traffic light poles involved in vehicle frontal collisions by developing a computer-based, finite-element model capable of capturing the impact characteristics. This is achieved by using the available non-linear dynamic analysis software "LS-DYNA3D", which can accurately predict the dynamic response of both the vehicle and the traffic light pole. The fiber reinforced polymer(FRP) as a new pole's material is proposed in this paper to increase energy absorption capabilities in the case of a traffic pole involved in a vehicle head-on collision. Numerical analyses are conducted to evaluate the effects of key parameters on the response of the pole embedded in soil when impacted by vehicles, including: soil type(clay and sand) and pole material type(FRP and steel). It is demonstrated from the numerical analysis that the FRP pole-soil system has favorable advantages over steel poles, where the FRP pole absorbed vehicle impact energy in a smoother behavior, which leads to smoother acceleration pulse and less deformation of the vehicle than those encountered with steel poles. Also, it was observed that clayey soil brings a slightly more resistance than sandy soil which helps reducing pole movement at ground level. Finally, FRP pole system provides more energy absorbing leading to protection during minor impacts and under service loading, and remain flexible enough to avoid influencing vehicle occupants, thus reducing fatalities and injuries resulting from the crash.

Calibration of hydrophone Coordinates by the Telemetry techniques (초음파 핑거를 이용한 수파기 좌표의 보정)

  • 신현옥
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.28 no.3
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    • pp.252-261
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    • 1992
  • The accuracy of the position fixing with telemetry techniques depends in general on the accuracy of the location of the receiving point(hydrophone). To increase the accuracy of the coordinates of four hydrophones suspended down at both sides of the vessel anchored, each hydrophone motion is compensated using a depth pinger mounted on the seabed of 30m depth. The pinger location is calculated with a hyperbolic method. Using this technique so called hydrophone coordinates calibration, the movement of the Remotely Operated Vehicle(ROV), which has the same type of pinger mentioned above could be tracked down more accurately. Under the maximum variation ranges of a hydrophone of 5.2m in athwartships, 3.2m in alongship, and about 0.2m/s of the moving velocity in both directions, the ROV track with calibration is more close to the reality than that without calibration Tow depth pingers of same frequency can be distinguished by the use of three factors; The pulse period, the phase and the pulse period variation allowed in acquisition of the pinger as far as its pulse period is varied in smooth.

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