• Title/Summary/Keyword: 이탈속도

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A Study on the Safety Performance of Roadside Barriers by Collision Analysis (방호울타리 안전성능에 관한 충돌해석 연구)

  • Lee, YounghHo;Song, Jae-Joon;Lee, Sang-Yoon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.11
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    • pp.5558-5565
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    • 2012
  • Roadside barriers are facility for preventing cars from out of path, and 7 classes of barrier are prescribed in criteria of road grades and speed limit, etc. However, overload and overspeed are increased according to improvement of vehicle performance, and falling over frequently occur in vehicle accident related in barriers. Therefore, enhancement of the existing design criteria of roadside barriers is demanded. In this research, vehicle crash simulation was carried out, and the condition for fracture of roadside barriers and vehicle overturn was evaluated in order to verify the defence performance of the barriers, which are SB5 steel barrier and SB6 concrete barrier adapted mainly to highway.

Study of Reading Aids for Improve Text Readability on a Small Screen Mobile Device (Small Screen Mobile 환경에서 가독성을 높이기 위한 Reading Aids의 연구)

  • Kim, Jong-Gon;Choi, Sun-Hyang;Min, Young-Sam
    • 한국HCI학회:학술대회논문집
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    • 2008.02a
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    • pp.147-151
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    • 2008
  • There are many attempts to transfer many applications from PC to mobile which has small screen, cause of a development of mobile technology. To display the whole information of the PC on the tiny screen, it makes many Horizontal Scroll, Horizontal Scroll in mobile screen makes people to miss where they are reading easily and such a frequent error makes readability of the information in mobile screen low. We suggest a Line Marker to help readability of the mobile screen high. This study shows the relationship between the conditions of Line Marker such as fixed or moved or not exists and the factors of the reading time and satisfaction.

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A numerical simulation of flow around an impulsively translating two dimensional circular cylinder using the diffusion vortex method (순간적으로 병진운동하는 2차원 원형실린더 주위 유동장의 확산와류방법 연구)

  • Seo, Ho-Won
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.32 no.6
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    • pp.9-15
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    • 2004
  • In this study the development of the two dimensional flowfield around an impulsively translated circular cylinder is numerically simulated using the diffusion vortex method. A detailed streamline pattern of fore wake and main wake of Re=1200, 9500 flowfields are investigated. The results of streamline pattern, the size of main wake and the axial velocities along the rear symmetry axis of the circular cylinder show good agreement with the reported experimental results. The long term wake delvelopment for Re=1200 flowfield was calculated up to ${\tau}=50$. The vortex shedding frequency shows the similar value as that of reported.

Design of a Fuzzy Controller for a Line Trace Vehicle (라인 트레이스 차량을 위한 퍼지 제어기의 설계)

  • Kim, Kwang-Baek;Woo, Young-Woon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.11
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    • pp.2289-2294
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    • 2009
  • In this paper, we proposed a fuzzy controller for racing of a line trace vehicle. Sensor values are computed by statuses of line detecting sensors attached to the line trace vehicle and these sensor values are used for fuzzy inference rules of steering angle control to decide steering angle as output. The decided steering angle is also used for fuzzy inference rules of motor speed control to decide motor speed as output. We experimented and analyzed two proposed methods - one is fuzzy control of steering angle only and the other is fuzzy control of both steering angle and motor speed. In the experiment, we verified that the second proposed method was more efficient in racing speed.

A Study on Youth Ethics Education Using Location-Based Services of Smartphone (스마트폰 위치기반서비스를 이용한 청소년 윤리교육에 관한 연구)

  • Ryu, Chang-Su;Hur, Chang-Wu
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.8
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    • pp.1805-1810
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    • 2012
  • As mobile devices have rapidly spread to consumers, services with location information have been developed. The service that they provide related information by positioning automatically is referred to as 'Location-Based Service'. This paper suggests the ways that users instruct the students proper ethics in advance, after saving their moving course and offensive businesses in database, with 'Location-Based Service', by positioning their movements, especially the degree of breaking away from their course and the cases of their access to an offensive business and their stay in crime-prone areas, and comparing them to those in the database.

Substituent Effects for the Menschutkin-Type Reaction of Substituted 2-Phenylethyl arenesulfonates with Substituted Pyridines (치환 2-Phenylethyl arenesulfonate 류와 치환 피리딘류의 Menschutkin 형 반응에 관한 치환기 효과)

  • Soo-Dong Yoh;Joong Hyup Kim
    • Journal of the Korean Chemical Society
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    • v.33 no.4
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    • pp.413-418
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    • 1989
  • The rates for the reaction of substituted 2-phenylethyl tosylates with substituted pyridines were measured in acetonitrile and that of 2-PNS with substituted pyridines were investigated in both acetonitrile and methanol. The substitutent effect was accelerated by an electron-donating substituent on both substrate and nucleophile. Results showed that More O'Ferrall and quantum mechanical model of predicting transition state structure suggest the reaction proceeds via an $S_N2$ mechanism, in which bond-breaking is more advanced than bond-formation. Transition state variation predicted with the quantum mechanical model is consistent with the experimental results, whereas the predictions provided by the More O'Ferrall plots is found to be inconsistent in leaving group. In the reaction of 2-PNS, the rate constants in acetonitrile were larger than that in methanol.

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Guidance Laws for Aircraft Automatic Landing (항공기 자동착륙 유도 법칙에 관한 연구)

  • Min, Byoung-Mun;No, Tae-Soo;Song, Ki-Jung
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.30 no.5
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    • pp.41-47
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    • 2002
  • In this paper, a guidance law applicable to aircraft automatic landing is proposed and its performance is compared with the conventional ILS-type landing approach. The concept of miss distance, which is commonly used in the missile guidance laws, and Lyapunov stability are effectively combined to obtain the landing guidance law. The new landing guidance law is integrated into the existing controller and is applied to the landing approach and flare phases of landing procedure. Numerical simulation results show that the new landing guidance law is a viable alternative to the conventional strategies that directly control the longitudinal deviation or altitude.

Control of powered descent phase for a Lunar lander using PID controller (PID 제어기를 이용한 달착륙선의 powered descent phase 유도제어)

  • Jo, Sung-Jin;Min, Chan-Oh;Lee, Dae-Woo;Cho, Kyeum-Rae
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.39 no.5
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    • pp.408-415
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    • 2011
  • The moon landing is composed of the de-orbit descent phase, powered descent phase, and the powered descent phase is divide into 3-sub phase of the braking, approach, final landing phase. In this paper, the lunar lander perform landing control using 3-sub phase of optimal trajectory. First, generate the reference trajectory using gauss pseudo-spectral method. Thereafter generate PID controller using altitude and velocity error in each direction. Finally the lunar lander landing system constitute using the Simulink of Matlab, and perform simulation.

Effect of Hydrogen in ITO(Indium Tin Oxide) Thin Films Etching by Low Temperature Plasma at Atmospheric Pressure (대기압 저온 플라스마에 의한 ITO(Indium Tin Oxide)박막 식각의 수소(H$_2$)효과)

  • Lee, Bong-Ju
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.39 no.8
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    • pp.12-16
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    • 2002
  • It is confirmed that the ITO(Indium Tin Oxide) thin films can be etched by low-temperature plasma at atmospheric pressure. The etching happened deepest at a hydrogen flow rate of 4 sccm, and the etch rate was 120 /min. The etching speed corresponded to the H$\alpha$* emission intensity The etching mechanism of the ITO thin films is as follows; thin films were reduced by H$\alpha$*, and the metal compound residues were detached from the substrate by reacting on the CH* The etching was started after etching time of initial 50 sec and above the threshold temperature of 145$^{\circ}C$. The activation energy of 0.16 eV(3.75 Kcal/mole) was obtained from the Arrehenius plots.

A Real-time Lane Tracking Using Inverse Perspective Mapping (역투영 변환을 이용한 고속도로 환경에서의 실시간 차선 추적)

  • Yeo, Jae-yun;Koo, Kyung-mo;Cha, Eui-young
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2013.10a
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    • pp.103-107
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    • 2013
  • In this paper, A real-time lane tracking algorithm is proposed for lane departure warning system. To eliminate perspective effect, input image is converted into Bird's View by inverse perspective mapping. Next, suitable features are extracted for lane detection. Lane feature that correspond to area of interest and RANSAC are used to detect lane candidates. And driving lane is decided by clustering of lane candidates. Finally, detected lane is tracked using the Kalman filter. Experimental results show that the proposed algorithm can be processed within 30ms and its detection rate is approximately 90% on the highway in a variety of environments such as day and night.

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