• Title/Summary/Keyword: Critical Extreme Position

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Precision Localization of Vehicle using AVM Image and RTK GPS for Urban Driving (도심 주행을 위한 AVM 영상과 RTK GPS를 이용한 차량의 정밀 위치 추정)

  • Gwak, Gisung;Kim, DongGyu;Hwang, Sung-Ho
    • Journal of Drive and Control
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    • v.17 no.4
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    • pp.72-79
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    • 2020
  • To ensure the safety of Advanced Driver Assistance Systems (ADAS) or autonomous vehicles, it is important to recognize the vehicle position, and specifically, the increased accuracy of the lateral position of the vehicle is required. In recent years, the quality of GPS signals has improved a lot and the price has decreased significantly, but extreme urban environments such as tunnels still pose a critical challenge. In this study, we proposed stable and precise lane recognition and tracking methods to solve these two issues via fusion of AVM images and vehicle sensor data using an extended Kalman filter. In addition, the vehicle's lateral position recognition and the abnormal state of RTK GPS were determined using this approach. The proposed method was validated via actual vehicle experiments in urban areas reporting multipath and signal disconnections.

Optical Proximity Correction using Sub-resolution Assist Feature in Extreme Ultraviolet Lithography (극자외선 리소그라피에서의 Sub-resolution assist feature를 이용한 근접효과보정)

  • Kim, Jung Sik;Hong, Seongchul;Jang, Yong Ju;Ahn, Jinho
    • Journal of the Semiconductor & Display Technology
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    • v.15 no.3
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    • pp.1-5
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    • 2016
  • In order to apply sub-resolution assist feature (SRAF) in extreme ultraviolet lithography, the maximum non-printing SRAF width and lithography process margin needs to be improved. Through simulation, we confirmed that the maximum SRAF width of 6% attenuated phase shift mask (PSM) is large compared to conventional binary intensity mask. The increase in SRAF width is due to dark region's reflectivity of PSM which consequently improves the process window. Furthermore, the critical dimension error caused by variation of SRAF width and center position is reduced by lower change in diffraction amplitude. Therefore, we speculate that the margin of SRAF application will be improved by using PSM.

Cam Profile Design for Precision Positioning (정밀위치결정을 위한 캠 형상 설계)

  • 이종호;이종길;김병희;전병희
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2003.05a
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    • pp.204-209
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    • 2003
  • Cam mechanisms are one of the most popular devices for generating intermittent motion and are widely used in many areas. Also, as being interested in research of precision field, cam mechanism is required high accuracy and continuity, In. In this paper, the cam mechanism of filament automatic assembly machine design for precision motion is proposed. The modelling of a cam mechanism, cam profile functions, and the design of the cam considering the precision positioning of the cam mechanism is studied. And, simulation of designed cam mechanism had been carried out dynamic analysis.

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A Study on Critical Understanding of Family Ideologies in Geun Hyung Park's Plays (박근형 연극에 나타난 가족 이데올로기에 대한 비판적 인식)

  • Kim, Sukkyung
    • Journal of Korean Theatre Studies Association
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    • no.48
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    • pp.85-125
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    • 2012
  • Geun Hyung Park is one of the playwrights who consistently pursues his unique world of play. One of the characteristics that is constantly discovered in Park's plays is the motif of 'family.' Park chooses family as the motif in most of his work. Park particularly emphasizes 'family life' rather than 'individual life' to focus on the internal problems of families. Therefore, the motif of family in Park's plays takes a very important position in the content and theme. The Korean society imposes unique value on families and possesses a strictly obstinate family ideology. Park observes distorted family relations or individuals who cannot be happy within their families to identify the problems related to the family ideology that is deeply rooted in the Korean society. This is one of the important backgrounds for which Park is constantly dealing with 'family life.' This study selected five of Park's most famous plays to specifically examine Park's critical understanding of family ideology. First, his criticizes extreme family egoism by depicting a family that cannibalizes people to keep the family full. Park chooses 'absurd time and space' and the extreme subject of 'human flesh' to warn his audiences about the awful consequences of family egoism. His , which is the only piece that deals with family history among the five pieces selected, criticizes Korea's unique family-centered ideology by humorously depicting the history of the Cho family that is all about maintaining and worshipping the its clan. He reveals the unethical and hypocritical attitudes of the Cho family for the audiences to reconsider the family-centered ideology of the Korean society. In , he talks about the son and the father who lose his ethical authority and fail to perform his paternal responsibilities to criticize the traditional family ideology of patriarchism and suggests the pessimistic future of patriarchism. contrasts a blood-related family with an irresponsible father and a quasi-family to criticize the identity of blood-related families. In , Park depicts a 'smelly house' of a family in agonizing relations to deny the family myth and the maternal myth. He clearly shows how the ideals of family myth and maternal myth are distant from the reality. In result of this study, Park's criticism of family ideology appears in various forms. He comprehensively criticizes both the general family problems and the unique family issues of Korea. The family ideology of Korea is currently undergoing a radical change. It has been long since the traditional family ideologies have exposed problems to show the signs of crisis. Also, there have emerged various forms of families, including single-parent families, one-person families, adoption families, and multi-cultural families. In this respect, Park's critical understanding of family ideologies allows you to see the obvious family forms from a new perspective and greatly contributes to awakening the essential questions about families. Park's work is noticeable among the various artistic and literature pieces that deal with family issues because of his extraordinary skills to capture the key issues inherent in the problems of family ideologies.

Fraunhofer Diffraction Pattern of a Periodic Hologram When the Input Beam Size is Similar to the Period of the Hologram (주기적인 홀로그램에 입사하는 레이저빔의 크기가 주기와 유사할 때의 프라운호퍼 회절 패턴에 대한 연구)

  • Go, Chun Soo;Lim, Sungwoo;Oh, Yong Ho
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.31 no.4
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    • pp.193-197
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    • 2018
  • The ratio of the period of a diffractive element to the input beam size is a critical parameter in a diffractive beam shaper. We measured and calculated the Fraunhofer diffraction patterns of a periodic hologram with an input beam size similar to the period of the hologram. The measured intensities show very complicated patterns and are strongly dependent upon the center position of the laser beam relative to the hologram. Using a diffraction formula for a periodic hologram, we calculated the diffracted light intensities and fit them to the measured ones. The measured and calculated intensities are in good agreement even when the beam diameter of the incident laser is similar to the period of the hologram. We can therefore use this formula to estimate the output of a periodic beam shaper even under such an extreme condition.

A complete S-shape feed rate scheduling approach for NURBS interpolator

  • Du, Xu;Huang, Jie;Zhu, Li-Min
    • Journal of Computational Design and Engineering
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    • v.2 no.4
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    • pp.206-217
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    • 2015
  • This paper presents a complete S-shape feed rate scheduling approach (CSFA) with confined jerk, acceleration and command feed rate for parametric tool path. For a Non-Uniform Rational B-Spline (NURBS) tool path, the critical points of the tool path where the radius of curvature reaches extreme values are found firstly. Then, the NURBS curve is split into several NURBS sub-curves or blocks by the critical points. A bidirectional scanning strategy with the limitations of chord error, normal/tangential acceleration/jerk and command feed rate is employed to make the feed rate at the junctions between different NURBS blocks continuous. To improve the efficiency of the feed rate scheduling, the NURBS block is classified into three types: short block, medium block and long block. The feed rate profile corresponding to each NURBS block is generated according to the start/end feed rates and the arc length of the block and the limitations of tangential acceleration/jerk. In addition, two compensation strategies are proposed to make the feed rate more continuous and the arc increment more precise. Once the feed rate profile is determined, a second-order Taylor's expansion interpolation method is applied to generate the position commands. Finally, experiments with two free-form NURBS curves are conducted to verify the applicability and accuracy of the proposed method.

The contents of the Education for Conversation and Negotiation, and its Sociopolitical Implication (대화와 협상교육의 내용과 사회정치적 함의)

  • Shin, Hee-sun
    • Journal of Ethics
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    • no.75
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    • pp.63-98
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    • 2009
  • The Social Conflict Index in Korea is considerably high. In the situation where both parties' interests conflict each other, Korean society has shown immature democracy, which couldn't peacefully resolve the conflict because of the lack of tolerance against the counterparty's position. In terms of upbringing educated citizens, who could democratically communicate with others and approach problems, communication skill training is very important, reducing social costs by extreme conflict. Thus, this paper studied the necessity of communication skills training and its sociopolitical implication through case studies about "Communication and Negotiation" class, which is proceeded under university liberal education. Under current university curriculums, increased liberal education programs, related with speaking, focus on cultivating logical and critical thinking in the main. Based on these thinking skills, "Communication and Negotiation" has important implication in terms of cultivating mindset which resolves conflicts and considers other's position by collaborative and emotional perspectives. In terms of cultivating practical communication skills, this "Communication and Negotiation" class requires the change of teaching skills with various training programs, under students' active participation and feedback in the class exercise for resolving problems. Ultimately, through "Communication and Negotiation" class, and as members of society, students could learn matured citizenship and sense of responsibility by respecting others' position and reasonably resolving conflicts.

Wind load and wind-induced effect of the large wind turbine tower-blade system considering blade yaw and interference

  • Ke, S.T.;Wang, X.H.;Ge, Y.J.
    • Wind and Structures
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    • v.28 no.2
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    • pp.71-87
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    • 2019
  • The yaw and interference effects of blades affect aerodynamic performance of large wind turbine system significantly, thus influencing wind-induced response and stability performance of the tower-blade system. In this study, the 5MW wind turbine which was developed by Nanjing University of Aeronautics and Astronautics (NUAA) was chosen as the research object. Large eddy simulation on flow field and aerodynamics of its wind turbine system with different yaw angles($0^{\circ}$, $5^{\circ}$, $10^{\circ}$, $20^{\circ}$, $30^{\circ}$ and $45^{\circ}$) under the most unfavorable blade position was carried out. Results were compared with codes and measurement results at home and abroad, which verified validity of large eddy simulation. On this basis, effects of yaw angle on average wind pressure, fluctuating wind pressure, lift coefficient, resistance coefficient,streaming and wake characteristics on different interference zone of tower of wind turbine were analyzed. Next, the blade-cabin-tower-foundation integrated coupling model of the large wind turbine was constructed based on finite element method. Dynamic characteristics, wind-induced response and stability performance of the wind turbine structural system under different yaw angle were analyzed systematically. Research results demonstrate that with the increase of yaw angle, the maximum negative pressure and extreme negative pressure of the significant interference zone of the tower present a V-shaped variation trend, whereas the layer resistance coefficient increases gradually. By contrast, the maximum negative pressure, extreme negative pressure and layer resistance coefficient of the non-interference zone remain basically same. Effects of streaming and wake weaken gradually. When the yaw angle increases to $45^{\circ}$, aerodynamic force of the tower is close with that when there's no blade yaw and interference. As the height of significant interference zone increases, layer resistance coefficient decreases firstly and then increases under different yaw angles. Maximum means and mean square error (MSE) of radial displacement under different yaw angles all occur at circumferential $0^{\circ}$ and $180^{\circ}$ of the tower. The maximum bending moment at tower bottom is at circumferential $20^{\circ}$. When the yaw angle is $0^{\circ}$, the maximum downwind displacement responses of different blades are higher than 2.7 m. With the increase of yaw angle, MSEs of radial displacement at tower top, downwind displacement of blades, internal force at blade roots all decrease gradually, while the critical wind speed decreases firstly and then increases and finally decreases. The comprehensive analysis shows that the worst aerodynamic performance and wind-induced response of the wind turbine system are achieved when the yaw angle is $0^{\circ}$, whereas the worst stability performance and ultimate bearing capacity are achieved when the yaw angle is $45^{\circ}$.

A Critical Review on the Comprehensive Cable TV Channels' Journalism Focused on the TV Politics of Political Mediating Elites in Current Affairs Talk Show (종합편성채널 저널리즘의 비판적 재조명 시사토크쇼 정치 매개 엘리트들의 텔레비전 정치)

  • Lee, Youngjoo
    • Korean journal of communication and information
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    • v.77
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    • pp.36-72
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    • 2016
  • Comprehensive Cable TV Channels(CCCs) has been established as a political product around 5 years ago, and it's influence and position on the broadcasting field are keep increasing. CCC's stabilization is based on flooding the market with journalism. The repeating news and current affairs programs are appearing constantly in the afternoon which is CCC's primetime. The current affairs talk shows are a product of CCC's representative program type and it leads unique CCC style journalism. The guests of the current affairs talk show leading the program with critiques(comments) and discussions about political issues. The purpose of this study is to explore how these guests of the current affairs talk shows conceptually positioned as political mediating elites and same time to explore the television political landscape through the representative current affairs talk shows from TV chosun, Channel A, MBN, JTBC which are present by these political elites. This study wants to find out about that television political effects from CCCs which exemplified into certain directions by these political mediating elites saying their political biases and expresses their feelings drastically that causes high ratings and brings people's attention. The guests who called political mediating elites in this study are mostly considered to be extreme rightist, conservatives, conservative-centrist and they have close relationship with certain political party or political group. The political mediating elites gain the popularities and have great influence on the public from performing the television politics through CCCs' current affairs talk shows and use that to make political exchange connections with political groups. Therefore this study wants to point out that CCCs' current affairs talk shows are situated in political rally, exchange connection, so current affairs talk shows are existing only for political battle field.

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