• Title/Summary/Keyword: 가/감속

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Resin Synthesis of 1-Aza-15-Crown-5-Styrene-divinylbenzene with Crosslink (가교도를 가진 1-Aza-15-Crown-5-스틸렌-디비닐벤젠 수지 합성)

  • 박성규;김준태;노기환
    • Journal of environmental and Sanitary engineering
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    • v.17 no.1
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    • pp.63-68
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    • 2002
  • Amount of styrene and divinylbenzene(DVB) was adjusted under injection of nitrogen, copolymer having crosslink of 1%, 2% and 5% was synthesized and zinc chloride was added to it. Put into benzene, swell it, add potassium iodide and 1-aza-15-crown-5 of 21.93g in toluene solution and functional resin which can adsorb heavy metal ions by stir reflex at $55^{\circ}C$ for 30 hours was synthesized. The content of divinylbenzene of this resin was increased as crosslink increase, macroporous gets smaller and the content of chlorine was reduced, which affects macrocyclic ligand in the process of substitution and content of nitrogen was also reduced. And the form of functional synthetic resin was distorted by substitution reaction of hydrogen and chlorine atoms.

PLL-type Position Control of Step Motors (스텝모터의 PLL 타입 위치제어)

  • Kim, Chang-Hwan
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.49 no.4
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    • pp.69-77
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    • 2012
  • We propose a PLL-type position control method for step motors. Our control method considerably improves the instability problem at rapid acceleration or deceleration, which is a major problem of conventional open loop control methods. Moreover, our controller reduces the steady state position error to zero and guarantees lower vibration and acoustic noise at high speed. Also, our controller can produce more torque at high speed, and hence it can extend the controllable velocity range. To demonstrate the practical significance of our control method, we present some simulation results for a commercially available step motor using Simulink.

The Effect of the ETC(Electronic Throttle Control) Characteristics on the Vehicle Driveability at Tip-in/out (스로틀 전자제어 방식에서 제어 특성이 차량의 가/감속 시 운전성에 미치는 영향)

  • Park, Kyoung-Seok;Lee, Jong-Hwa;Park, Jin-Il
    • Transactions of the Korean Society of Automotive Engineers
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    • v.13 no.6
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    • pp.113-119
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    • 2005
  • The passenger car drivers want in general to feel good driveability, but they sometimes feel uncomfortable by shock and jerk phenomenon when they push or release acceleration pedal with clutch engaged. In this paper, the shock and jerk characteristics are studied on the vehicles of the throttle-by-wire system. With this system, the throttle is not directly controlled by drivers but via a microprocessor. So the control logic of the throttle is very important on tip-in and tip-out driveability. Experiments were carried out on two vehicles which show different control characteristics. The torque control logics were analyzed by measuring cylinder pressures. The results show that special torque control logic is needed at tip-in/out state for good driveability.

Deadlock-free Routing of an ACV in Accelerated Motion (가감속을 고려한 교착없는 AGV 주행경로설정)

  • Choe, Ri;Park, Tae-Jin;Ryu, Kwang-Ryel
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.1
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    • pp.387-392
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    • 2006
  • In the environment where AGVs(Automated Guided Vehicles) operate concurrently in limited space, collisions. deadlocks, and livelocks which have negative effect on the productivity of AGVs occure more frequently. The accelerated motion of an AGV is also the factor that make the AGV routing more difficult because the accelerated motion makes it difficult to estimate the vehicle's exact travel time. In this study, we propose methods of avoiding collisions, deadlocks, and livelocks using OAR(Occupancy Area Reservation) table, and selecting best route by estimating the travel time of an AGV in accelerated motion. A time-driven simulation validated the effectiveness of the proposed methods.

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Preliminary Study on Applicability of Accumulate Personal Neutron Dosimeter for Cosmic-ray Exposure of Aviators (운항승무원의 우주방사선 피폭 평가에 있어 누적형 개인 중성자 선량계의 적용가능성 예비 연구)

  • Kim, Hyeong-Jin;Chang, Byung-Uck;Byun, Jong-In;Song, Myeong Han;Kim, Jung-Ho
    • Journal of Radiation Protection and Research
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    • v.38 no.1
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    • pp.44-51
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    • 2013
  • ICRP recommended that cosmic ray exposure to the pilot and cabin crew would be considered as an occupational exposure due to their relatively high exposure. Since 2012 with the Act No. 10908 (Natural radiation management), the guideline of cosmic ray exposure to the pilot was established in Korea. The applicability of the solid-state nuclear track detector for personal dose assessment of pilot and cabin crew was evaluated. Dose linearity and angle dependence of dosimeters to the neutron were evaluated by $^{252}Cf$ neutron emitting source. The track density has a good agreement with the dose ($r^2$=0.99) and highly dependent on the degree of an angular of the dosimeter to the neutron source. In addition, the dosimeters (SSNTD) were exposed to cosmic ray in an aircraft during its cruising for more than two months in collaboration with Airline Pilots Association of Korea. Although the correlation between the track density from aircraft cruising altitude and expected neutron dose is low, however RSNS dosimeter could be used for personal neutron dosimeter. For application of RSNS as a personal dosimeter for pilot and cabin crew, additional studies are required.

An Analysis on the Importance of Planning Indicator of Traffic Calming Technique for Walk Safety - Focusing on Physical Side - (보행안전을 위한 교통정온화(Traffic Calming) 계획지표의 중요도 분석 - 물리적인 측면을 중심으로 -)

  • Yoon, Sanghoon;Choi, Hyoungsun;Lee, Joohyung
    • Journal of the Society of Disaster Information
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    • v.11 no.4
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    • pp.570-580
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    • 2015
  • In the study, planning indicator that should be considered in applying traffic calming technique was derived, and it was intended to analyze the importance of indicator that should most considered in planning traffic calming technique through AHP analysis on the basis of it. The result of planning indicator may be summarized by dividing into road section and crossing section. In road section, hump (0.35) for equipment stimulating reduction of speed, hump image/fort (0.31) for visual control equipment, and slalom type road (0.52) for chicane, and bollard (0.47) for blocking passing route are shown to be the most important and come before anything. In crossing section, signal indicator (0.33) for visual control equipment, rumble strip (0.44) for equipment stimulating reduction of speed, zigzag type road (0.65) for chicane, and blocking going straight at crossing (0.45) for blocking passing route are shown to be the most important and come before anything. The result of the study is judged to be used for basic material in applying traffic calming technique and establishing policy hereafter.

Deadlock-free Routing of an AGV in Accelerated Motion (가감속을 고려한 교착없는 AGV 주행경로설정)

  • Choe, Ri;Park, Tae-Jin;Ryu, Kwang-Ryel
    • Journal of Navigation and Port Research
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    • v.30 no.10 s.116
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    • pp.855-860
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    • 2006
  • In the environment where multiple AGVs(Automated Guided Vehicles) operate concurrently in limited space, collisions, deadlocks, and livelocks which have negative effect on the productivity of AGVs occure more frequently. The accelerated motion of an AGV is also one of the factors that make the AGV routing more difficult because the accelerated motion makes it difficult to estimate the vehicle's exact travel time. In this study, we propose methods of avoiding collisions, deadlocks, and livelocks using OAR(Occupancy Area Reservation) table, and selecting best route by estimating the travel time of an AGV in accelerated motion. A set of time-driven simulation works validated the effectiveness of the proposed methods.

Unmanned Ground Vehicle Control and Modeling for Lane Tracking and Obstacle Avoidance (충돌회피 및 차선추적을 위한 무인자동차의 제어 및 모델링)

  • Yu, Hwan-Shin;Kim, Sang-Gyum
    • Journal of Advanced Navigation Technology
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    • v.11 no.4
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    • pp.359-370
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    • 2007
  • Lane tracking and obstacle avoidance are considered two of the key technologies on an unmanned ground vehicle system. In this paper, we propose a method of lane tracking and obstacle avoidance, which can be expressed as vehicle control, modeling, and sensor experiments. First, obstacle avoidance consists of two parts: a longitudinal control system for acceleration and deceleration and a lateral control system for steering control. Each system is used for unmanned ground vehicle control, which notes the vehicle's location, recognizes obstacles surrounding it, and makes a decision how fast to proceed according to circumstances. During the operation, the control strategy of the vehicle can detect obstacle and perform obstacle avoidance on the road, which involves vehicle velocity. Second, we explain a method of lane tracking by means of a vision system, which consists of two parts: First, vehicle control is included in the road model through lateral and longitudinal control. Second, the image processing method deals with the lane tracking method, the image processing algorithm, and the filtering method. Finally, in this paper, we propose a method for vehicle control, modeling, lane tracking, and obstacle avoidance, which are confirmed through vehicles tests.

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A Study on the Aerodynamic Force Augmentatation Panel for Improving Lift-Drag Characteristics at High Angle of Attack (높은 받음각에서 양항 특성의 향상을 위한 공력 보조 PANEL에 관한 연구)

  • Shin, Dong-Jin;Lee, Bong-Jun
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.2
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    • pp.57-80
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    • 1994
  • 항공기에 사용되는 2차 조종면은 플랩, 탭, 스포일러 등 여러 종류가 있으며 이중 spoiler는 공력제어 기능을 가지고 항공기의 조종성에 영향을 미치는 조종면으로 속도 감속이나 옆놀이 조종용으로 사용된다. 본 연구에서는 비행제어용 spoiler 기능과 고양항력을 얻을 수 있는 새로운 장치인 고양항력 panel에 대한 공력특성 및 비행제어 특성에 대하여 연구하였다. 이러한 고양항력 panel은 재래식인 spoiler가 양력을 감소시키고 항력만 증가시키는 장치인데 반하여 양력과 항력을 동시에 증가 시킬 수 있는 새로운 장치로서 날개의 앞전 윗면에 스팬방향으로 설치하여 슬롯효과를 발생시킴으로써 최대 양력 받음각에서 앞전에서의 박리를 막아 비행기의 착륙시 양력의 급작스러운 감소로 인한 불안정성을 감소시키게 된다. 본 논문에서는 직사각형 날개 및 FA-200모형의 날개위에 고양항력 panel을 설치하여 풍동실험 및 수치계산을 한 결과를 기술하였다. 실험결과 직사각형 날개의 경우 고양항력 panel의 위치는 날개의 앞전에 설치할 경우 고받음각에서 실속지연의 효과와 함께 후방실속의 특성을 향상 시킬 수 있으며, 항력의 증가로 인한 스포일러 효과를 얻을 수 있다. 양항비특성은 고양항력 panel을 날개의 앞전에설치하고, 그폭이 시위의 1/5이고, 붙임각 ${\theta}$$10^{\circ}$, 높이가 시위의 3/20일때 받음각 $18^{\circ}$ 이후에서 우수한 특성을 나타내었다. FA-200 모형의 경우 옆놀이 모멘트계수는 받음각이 작을 때 고양항력 panel의 슬롯간격과 붙임각이 작을수록 커지나 받음각이 커지면 붙임각이 커짐에 따라 증가함을 알 수 있다. 또한 키놀이 모멘트계수는 크게 변화하지 않으나 항력 특성은 고양항력 panel의 붙임각이 증가함에 따라 증가하였다. 고양항력 panel의 붙임각이 큰 범위에서 (${\theta}$ =$10^{\circ}$) 공기력의 증가는 고양항력 panel의 시위가 날개시위의 30%이고 슬롯의 폭이 날개시위의 10%일때 증가하는 결과를 얻을 수 있다.

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Turbojet Engine Control of UAV using Artificial Neural Network PID (인공신경망 PID를 이용한 무인항공기 터보제트 엔진 제어)

  • Kim, Dae-Gi;Hong, Gyo-Young;Ahn, Dong-Man;Hong, Seung-Beom;Jie, Min-Seok
    • Journal of Advanced Navigation Technology
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    • v.18 no.2
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    • pp.107-113
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    • 2014
  • In this paper, controller Propose to prevent compressor surge and improve the transient response of the fuel flow control system of turbojet engine. Turbojet engine controller is designed by applying Artificial Neural Network PID control algorithm and make an inference by applying Artificial Neural Network Error Back Propagation Algorithm. To prevent any surge or a flame out event during the engine acceleration or deceleration, the ANN PID controller effectively controls the fuel flow input of the control system. ANN PID results are used as the fuel flow control inputs to prevent compressor surge and flame-out for turbo-jet engine and the controller is designed to converge to the desired speed quickly and safely. Using MATLAB to perform computer simulations verified the performance of the proposed controller. Response characteristics pursuant to the gain were analyzed by simulation.