• 제목/요약/키워드: Stillness

검색결과 36건 처리시간 0.02초

로봇 매니퓰레이터의 퍼지 강성 제어 (Fuzzy stiffness control of Robot manipulator)

  • 강상태;지종환;홍석교
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1998년도 하계학술대회 논문집 G
    • /
    • pp.2354-2356
    • /
    • 1998
  • We present a fuzzy model for a robot manipulator and use the model to decide the PD gains of a stiffness controller. Force control applications are extremely difficult to accomplish with such a stiffness robot because robot itself, unknown environment. So we identify a fuzzy model by using Hough transform. We present a method of design of the PD gains of the stiffness controller. We aim at controlling the end-effecor force in the face of uncertainty on the surface stillness. simulation results verify the effectiveness of the proposed strategy.

  • PDF

New Evaluation and Test of Sidewall's Rotational Stiffness of Radial Tire

  • Kim Young-Woo;Kim Yong-Sung
    • Journal of Mechanical Science and Technology
    • /
    • 제20권6호
    • /
    • pp.748-758
    • /
    • 2006
  • In this paper, we have revisited the estimation of the rotational stiffness of sidewall of radial tire and have suggested a new method for evaluation of the rotational stiffness. Since thicknesses, and volume fractions of the constituents of sidewall are varied depending on radial position, the equivalent shear modulus of the sidewall also depends on radial position. For the estimation of rotational stiffness of sidewall's rubber, we have divided its cross-section into sufficient numbers of small parts and have calculated the equivalent shear modulus of each part of sidewall. Using the shear moduli of divided parts, we have obtained the rotational stiffness by employing in-plane shear deformation theory. This method is expected to be a useful tool in tire design since it relates such basic variables to the global stillness of tire. Applying the calculation method to a radial tire of P205/60R15, we have compared its rotational stiffness with experimental one.

전면벽체 강성에 따른 쏘일네일링 벽체의 거동특성에 관한 실험적 고찰 (An Experimental Study on Behavior Characteristic of the Soil Nailed Wall with Facing Stillness)

  • 김홍택;강인규;권영호;조용훈
    • 한국지반공학회:학술대회논문집
    • /
    • 한국지반공학회 2002년도 봄 학술발표회 논문집
    • /
    • pp.279-286
    • /
    • 2002
  • Recently, there are many attempts to expand a temporary soil nailing system into a permanent wall due to the advantage of soil nailing system, that is efficient and economic use of underground space and decreasing the total construction cost. However, the proper design approach of a permanent soil nailing system has not been proposed by now in Korea. Permanent soil nailing system which utilizes precast concrete walls for the facing of soil nailing system Is already used in many countries. In general, the cast-in-place concrete facings or rigid walls were constructed in bottom-up way after construction of soil nailing walls finished preliminarily In this paper, various laboratory model tests have been carried out to investigate the failure mode, behavior characteristics, and tensile force at nail head in each load level in respects of the variation of stiffness of the facing.

  • PDF

설계파라미터 변경에 따른 구조물의 동특성 변화 해석 (A Structural Eigenderivative Analysis by Modification of Design Parameter)

  • 이정윤
    • 대한기계학회논문집A
    • /
    • 제26권4호
    • /
    • pp.739-744
    • /
    • 2002
  • This study predicts the modified structural eigenvectors and eigenvalues due to the change in the mass and stiffness of a structure by iterative calculation of the sensitivity coefficient using the original dynamic characteristics. The method is applied to examples of a cantilever and 3 degree of freedom lumped mass model by modifing the mass and stillness. The predicted dynamic characteristics are in good agreement with these from the structural reanalysis using the modified mass and stiffness.

포스트필름 변신과 리애니메이션: '편재하는 애니메이션'의 기법적, 미학적 계보들 (Postfilic Metamorphorsis and Renaimation: On the Technical and Aesthetic Genealogies of 'Pervasive Animation')

  • 김지훈
    • 만화애니메이션 연구
    • /
    • 통권37호
    • /
    • pp.509-537
    • /
    • 2014
  • 이 논문은 수잔 부칸(Suzanna Buchan)이 말한 '편재하는 애니메이션'의 미학적 경향들과 계보들을 설명하기 위해 '포스트필름 변신'과 '리애니메이션'이라는 두 가지 개념을 제시한다. '편재하는 애니메이션'이란 애니메이션의 형태적, 기술적, 경험적 경계가 전례없이 확장되었음을 가리키는 범주다. 부칸은 '편재하는 애니메이션'을 이끈 현상들로 전통적인 애니메이션의 정의를 초월하는 이미지와 미디어들(CGI, 필름과 비디오의 실사 이미지, 그리고 전통적인 극장 바깥의 미디어와 플랫폼에 존재하는 다양한 애니메이션 이미지들)이 애니메이션의 장으로 포용되고 있음을 지적하면서 애니메이션에 대한 교차학제적 접근의 필요성을 지적한다. 부칸이 이러한 교차학제적, 혼종적 장을 가능케 한 결정적인 요소로 디지털 기술의 영향을 시사하는 반면, 나는 이 장에서 발견할 수 있는 다양한 변신과 운동의 양상들이 역사적 뿌리를 갖고 있음을 주장하기 위해 '포스트필름 변신'과 '리애니메이션'이라는 개념을 발전시킨다. 즉 '포스트필름 변신'이란 비디오와 컴퓨터 이미지에서의 변형적 이미지가 전통적 셀룰로이드 기반 애니메이션에서의 변형적 이미지와 물질적, 기법적으로 다르다는 점을 뜻하는데 이는 실험 애니메이션으로 범주화되었으나 전반적으로 주변화된 '이미지-프로세싱' 비디오아트와 디지털 이미지 사이의 연관관계에 대한 새로운 성찰을 요구한다. 마찬가지로 '리애니메이션'은 사진과 회화 등 정지영상 또는 영화와 비디오 이미지 등의 동영상을 취하여 일련의 기술적, 기법적 작용들로 다시 움직이는 것으로 실험영화와 오늘날의 무빙 이미지 설치작품에서 정지/운동, 사진/영화의 엄밀한 분리를 재고하기 위해 탐구되었다. 무라타 다케시, 다비드 클레르부, 켄 제이콥스 등의 오늘날의 작품들에서 나타나는 '포스트필름 변신'과 '리애니메이션'의 양상들을 그 선구적 사례들과 나란히 논의함으로써 이 논문은 '편재하는 애니메이션'에 속하는 작품들은 그것들이 전통적인 애니메이션을 지탱했던 그래픽/실사 이미지, 정지/운동의 이분법들에 도전하기 때문에 중요하다는 점을 주장한다. 이때 이 논문이 제시하는 두 개념은 '편재하는 애니메이션'을 새롭게 이해하는 방식으로서 전통적 애니메이션 바깥에 있던 이미지와 미디어의 역사와 존재론에 대한 수정주의적 접근의 필요성에 응답한다.

사랑의 변주곡에 대한 기호학적 접근 (A Semiological Study of Kim Soo-Young′s ″A Variation of Love″)

  • 한명희
    • 인문언어
    • /
    • 제1권2호
    • /
    • pp.47-63
    • /
    • 2001
  • "A Variation of Love" is a characteristic Kim Soo-Young poem, in that it embodies the poet′s innovative use of language and proceeds speedily, like many of his other poems. Above all, the poem reveals the core of Kim′s poetical spirit, his speculation about love. The poem is difficult to understand because it broadly uses run-on lines and even run-on stanzas, a technique that many readers are unfamiliar with. The semiological approach of this paper will bring new light on the poem by restructuring the relationship between signs, that is, by taking apart the sign system of the original text and reconstructing its sentence structure. If we rearrange the poem from its original six stanzas and fifty-one lines to four stanzas and twenty-three lines, we will discover a close connection between stanzas 1 and 2, and between stanzas 3 and 4. Of the many keywords of the poem, we may establish the dominant word as "love," into which every poetic word converges and from which each word emanates. Another important keyword is "fatigue of the city" in stanza 4. Similarly negative aspects of the city may be found in the line "the same may be said of Bombay, of New York, of Seoul" in stanza 3, as well as in the words "desire" in combination with "the lamplights of Seoul like leftovers in the pig sty" in stanza 1. The persona of the poem tries to overcome the "fatigue of the city" by "love," but the way he realizes love is, somewhat peculiarly, through stillness and silence. The persona aligns "the stones of the peach and the apricot and the dried persimmon" with the his faith in love. He calls the stones "beautiful hardness" presumably because that hardness (the stillness and silence) may blossom into beauty. In the earlier stanzas, the persona′s quest for love results in an awareness that love is omnipresent, but the persona determines "not to shout it out loud." The reason for this determination is found in stanza 4. Those who experience the "fatigue of the city" will be able to realize it by themselves. This seemingly defeatist conclusion by no means suggest pessimism, for the persona holds the conviction that "there will come a day when [one] will rave for love." This conviction rescues the poem from the dismal mood suggested by the "fatigue of the city." At all events, it is important to note that the "fatigue of the city" should not be considered apart from "love." Yet, strangely enough, the poem embodies a severe critique of the city, and further investigation is necessary in order to clarify why this critique appears in the form of "love." But this will be the treated in another paper.

  • PDF

스마트 스킨 구조물 시편의 유한요소 해석 (FEM Analysis of Smart Skin Structure Specimen)

  • 전지훈;황운봉
    • Composites Research
    • /
    • 제16권4호
    • /
    • pp.59-65
    • /
    • 2003
  • 샌드위치 구조물의 응용된 형태인 스마트 스킨 구조물을 ABAQUS로 유탄요소 해석하였다. 심재로 쓰이는 하니컴은 일반적으로 두께 방향 강성 및 전단 강성만 제작회사에 의하여 제공된다. 이를 바탕으로 하니컴 재료의 물성을 추정하여 다른 방향의 제공되지 않는 물성을 계산하였고, 이를 유탄요소 해석시 물성 자료로 적용하였다. 또한, 스마트 스킨 구조물의 좌굴 및 3점 굽힘 거동을 유한요소 해석하였으며, 기존의 실험결과 및 이론값과 비교 분석하였다. 비교적 결과가 잘 일치하였다. 본 연구를 통하여서 하니컴의 물성을 상용 패키지에 적용하는 방법 및 타당한 근거를 제시하였고, 이 결과를 바탕으로 스마트 스킨 구조물을 상용패키지로 유한요소 해석시 지침을 제시할 수 있다

드로우바와 로터가 고속주축계의 동적 특성에 미치는 영향 (Effects of a drawbar and a rotor in dynamic characteristics of a high-speed spindle)

  • 정원지;이춘만;이정환;임정숙
    • 한국정밀공학회지
    • /
    • 제23권3호
    • /
    • pp.139-146
    • /
    • 2006
  • The spindle system with a built-in motor can be used to simplify the structure of machine tools, to improve the machining flexibility of machine tools, and to perform the high speed machining. For more quantitative analysis of a built-in motor's dynamic characteristics, that of tile mass and stillness effects are considered. And the drawbar in the spindle can be in various condition according to supporting stiffness between drawbar and shaft. Therefore, in this paper following items are performed and analyzed : 1. Modal characteristics of the spindle. 2. Analysis of rotor's mass and stiffness effects. 3. Modal characteristics of the spindle including drawbar, rotor and tool. The results show enough stiff supports must be provided between shaft and drawbar to prevent occurring drawbar vibration lower than the natural frequency of 1st bending mode of the spindle, and considering the mass and stiffness of built-in motor's rotor is important thing to derive more accurate results.

슬골관절염 환자를 위한 타이치운동, 수중운동과 자조관리프로그램의 효과비교 (Comparison of Effects among Tai-Chi Exercise, Aquatic Exercise, and a Self-help Program for Patients with Knee Osteoarthritis)

  • 이혜영
    • 대한간호학회지
    • /
    • 제36권3호
    • /
    • pp.571-580
    • /
    • 2006
  • Purpose: This study was to compare the effects among Tai-Chi exercise, aquatic Exercise, and a self-help program for knee osteoarthritis patients on symptoms of arthritis, muscle strength, balance, and difficulty of performing activities. Method: There were 50 final subjects50. A non-equivalent pretest-posttest design was used. The collected data was analyzed using SPSS for Window. One-way ANOVA and Scheffe's multiple comparison test were used 8weeks after each program. Result: There were significant differences in joint pain(p=.000), stillness (p=.001), knee extensor peak torque(p=.006), knee flexor(p=.002), and difficult of performing activity (p=.000), but there was no significant difference in balance(p=.648). The Tai-Chi group was significantly different from the self-help group for knee extensor peak torque, knee flexor and stiffness on Scheffe's multiple comparison tests. In addition, the Tai Chi group or aquatic group were significantly different from the self-help group for difficulty of performing activities(p<0.05). Conclusion: There are significant differences in the effects of the nursing intervention among the three groups. The Tai Chi group and aquatic group were significantly different from the self-help group. However, it seems that Tai-chi exercise may be more suitable than aquatic exercise in osteoarthritis exercise programs. Further studies with a longitudinal study are necessary to confirm the longer exercise period.

연(蓮) 이미지를 활용한 직물디자인 개발 - 디지털 사진 이미지를 중심으로 - (The Development of Textile Designs by Using Images of Lotus - Focused on Images of Digital Photograph -)

  • 정진순
    • 복식
    • /
    • 제61권9호
    • /
    • pp.50-59
    • /
    • 2011
  • Recently the word "digital" is widely used in almost every field and is dominating this generation. Digital has become the most significant characteristic representing the 21st century, and is leading change across wide range of our life-styles in our culture and thoughts. New art is in harmony with digital in the 21st century. Digital photography is simpler, faster and newer than the analog system of the past. From ancient times, the nature has been the subject of art, and many designers have studied the ways to create beauty from nature. In this study, I chose the lotus as the subject material of textile design development. The lotus invokes a sense of stillness, and nestles many fluid elements, including the curved fluid lotus, rhythmic lotus petal, sinuous lotus leaf, radial vein, lotus pip and oval seed. Therefore, I tried to use these elements of lotus for development of textile design. For this purpose, I photographed the lotus with a digital camera as equipment of design development. Then, on computer, I have developed six textile designs through the process of modification and editing by using the adobe illustrator program.