• 제목/요약/키워드: great freedom

검색결과 107건 처리시간 0.028초

해상풍력터빈에 대한 하중 모사 방법 연구 (Load simulation for offshore wind turbine)

  • 석상민;이성건;정진화;박현철
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 한국신재생에너지학회 2011년도 춘계학술대회 초록집
    • /
    • pp.58.1-58.1
    • /
    • 2011
  • In this paper, the purpose is a study on structural analysis for offshore wind turbine using commercial code. Because offshore wind turbine is subjected to great wind and wave force, it is necessary to analyse the dynamics and minimize the response of wind turbine. The offshore wind turbine tower is modelled as a single degree of freedom and multi degree of freedom structure. It is assumed that the blades, nacelle are composed of concentrated masses.

  • PDF

단자유도계를 이용한 충격흡수시설의 설계법 개발 (Study on the Design Method Development of Crash Cushion Using Single Degree of Freedom)

  • 주재웅;금기정;장대영;손승녀
    • 한국도로학회논문집
    • /
    • 제9권3호
    • /
    • pp.91-100
    • /
    • 2007
  • 도로를 이용하는 운전자들의 안전을 위해서 없어서는 안될 차량방호안전시설이 충격 흡수시설이다. 그러나 충격 흡수시설의 합리적이고 현실적인 설계방법이 미비한 상태임으로 대안없이 충돌시험에만 의존하고 있고 이것으로 인해 시간적, 물리적 손실이 큰 실정이다. 본 연구에서는 실차 충돌시험 데이터를 이용하여 삼차원의 복잡한 충돌거동에 대해 탑승자의 안전을 고려한 단자유도계 적용의 적합성을 증명하고 충격흡수시설의 거동을 분석함으로써 효과적인 단자유도계 충격흡수시설 설계법을 개발하고자 했다. 그리하여 단자유도계를 이용한 충돌해석 모델을 정립하고 충격흡수시설 설계법을 제시하였다. 충격흡수시설 설계법의 유효성을 검증하기 위해 단자유도계 설계법으로 CC2등급 충격흡수시설을 설계 제작하여 실차 충돌시험을 실시하였다. 성능시험 결과 매우 만족스러운 결과가 도출되었고 이로써 단자유도계 충격흡수시설 설계법은 충격흡수시설을 설계하는데 있어 유용한 방법중의 하나임이 증명되었다.

  • PDF

Mathematical Model of Two-Degree-of-Freedom Direct Drive Induction Motor Considering Coupling Effect

  • Si, Jikai;Xie, Lujia;Han, Junbo;Feng, Haichao;Cao, Wenping;Hu, Yihua
    • Journal of Electrical Engineering and Technology
    • /
    • 제12권3호
    • /
    • pp.1227-1234
    • /
    • 2017
  • The two-degree-of-freedom direct drive induction motor, which is capable of linear, rotary and helical motion, has a wide application in special industry such as industrial robot arms. It is inevitable that the linear motion and rotary motion generate coupling effect on each other on account of the high integration. The analysis of this effect has great significance in the research of two-degree-of-freedom motors, which is also crucial to realize precision control of them. The coupling factor considering the coupling effect is proposed and addressed by 3D finite element method. Then the corrected mathematical model is presented by importing the coupling factor. The results from it are verified by 3D finite element model and prototype test, which validates the corrected mathematical model.

Research on Satisfaction Evaluation Based on Tourist Big Data

  • Guo, Hanwen;Liu, Ziyang;Jiao, Zeyu
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • 제16권1호
    • /
    • pp.231-244
    • /
    • 2022
  • With the improvement of people's living standards and the development of tourism, tourists have greater freedom in choosing destinations. Therefore, as an indicator of satisfaction with scenic spots, tourist comments are becoming increasingly prominent. This paper aims to compare and analyze the landscape image of the Five Great Mountains in China and provide specific strategies for its development. The online reviews of tourists on the Online Travel Agency (OTA) website about the Five Great Mountains from 2015 to 2018 are collected as research samples. The text analysis method and R language are used to analyze the content of the tourist reviews, while the high-frequency words in the word cloud are used for visual display. In addition, the entropy weight method is used to determine the index weight and tourist satisfaction is evaluated to understand the weaknesses of those scenic spots. The results of the study show that firstly, the tourist satisfaction with the Five Great Mountains is basically consistent with its popularity. Secondly, through weight analysis, tourists pay special attention to the landscape features and environmental health of the scenic area, so that relevant departments should focus on building the landscape characteristics and improving the environmental health of the scenic area. At the same time, the accommodation and service management of the scenic spot cannot be ignored. Finally, according to the analysis results, suggestions are made on how to improve the tourist satisfaction with the Five Great Mountains.

현대 패션에 나타난 Eroticism 에 관한 연구-초현실주의와 팝 아트의 Eroticism을 중심으로

  • 이효진
    • 복식
    • /
    • 제23권
    • /
    • pp.111-130
    • /
    • 1994
  • The purpose of this study was to illuminate eroticism represented din modern fashion. Art based on sex is very important like all of the other cultural values. But we feel that erotic art, neglected, suppressed , and persecuted for centuries, has an important contribution to make to the understanding of art, the social history of mankind, and human happiness and progress. It is our deep personal conviction that erotic art serves important social and therapeutic functions. Erotic art expresses the demand for sexual freedom-a freedom vital to individual happiness and mental well-being, And sexual freedom, in turn, cannot exist without a high degree of political and economic freedom as well. In that sense , erotic art came a truly revolutionaly message ; it demands no less than extension of freedom , not only in the sexual are, but in every sphere of social life. What is eroticism \ulcorner Eroticism must be distinguished from a mere animal reproduction . Eroticism is deeply rooted in the cultural tradition of myth, religion , customes and art. It also has a close relationship with psychological activities of our life. Eroticism is a kind of psychological revolution in the development of human civilization. Eroticism is related to different kinds of art, which express internal spirit of human especially Surrealism. Surrealism is above all a movement of the conquest and deepening of the unconscious. The exploitation of Freud's discoveries opended a new, practically unlimited path for artistic studies to Surrealism . Especially all theory of mental psychoanalysis a affected artists greatly in western art, Freud was appraised highly on his achievements by art critics in art history on his achievements by art critics in art history. As far as erotic subject matter was concerned, Surrealism provided a means of presentig it. Pop Art is not actually a movement , born at a specific time and place, nor is it an easy concept to define. The term first appeared in Great Britain during the fifties, when it referred, particularly in the decorative arts, to an inclination to go back and imitate the stereotyped images of the mass media : film, advertising , cartoons, and other popular consumer products. The eroticism expressed in Pop Art calls the modern's attentions to their devastated minds, taking advantage of the commercialized sex. Fashion has developed constantly reflecting the spiritual aspiration and social and cultural phenomona of man , and artistic steam. Eroticism in fashion is the style which expresses the internal meanings of sexuality through the texture, color, pattern , silhouette etc.

  • PDF

이득 설계가 간단한 선형전동기 2자유도 PID 위치제어기 구현 (Implementation of the two-degree-of freedom PID Position Controller for Linear Motor Drive with Easy Gain Adjustment)

  • 하홍곤;이창호
    • 융합신호처리학회논문지
    • /
    • 제8권2호
    • /
    • pp.124-129
    • /
    • 2007
  • 최근, 반도체장비, 공구이송장비 그리고 CNC같은 여러 산업분야에 선형기계의 응용이 크게 증가하고 있다. 그러나 선형전동기는 진동특성을 가지고 있다. 그러므로 이러한 응용분야에서 정상 및 과도응답상태에서 고성능 위치제어가 필요하게 된다. 본 논문에서 간단하면서도 강력한 위치제어법을 2자유도 PID제어기를 이용하여 제안하였다. 이 기법은 과도현상없이 선형기계를 구동할 수 있는 잇점과 간단한 이득 동조를 할 수 있다. 일반적인 PID 제어기에 비해서 2자유도 제어기를 사용한 선형 전동기의 제어계의 성능 향상이 논의되었다. 그리고 시뮬레이션의 결과로 위치제어계의 응답에서 과도응답과 기동특성의 향상, 그리고 불필요한 진동성분의 제거에 유효함을 확인하였다.

  • PDF

재즈시대의 문화와 소설을 통해본 플래퍼 이미지 (A Study on Flapper Image through the Culture and Novels in Jazz Age)

  • 박혜원
    • 한국의류학회지
    • /
    • 제24권2호
    • /
    • pp.173-184
    • /
    • 2000
  • The purposes of this study is for consideration of the flapper image through the culture and novels in Jazz Age(1919∼1929) of America. The back ground of flapper fashion was Jazz. Jazz was one of the cultural languages which expressed liveness, noise, salacity, harmony of primitivity, modernity, innocence and freedom. In processing American had gotten economic power, the Jazz Age had new mood which was combined materialism and realitism. Environmental changes of life styles and development of mass culture of modern big cities could aid the birth of modern girls, flappers. They became the main group of new consumer and mass culture in new consciousness and freedom with independence. Their characteristics are confirmed from Fitzgerald's novels, This Side of Paradise and The Great Gatsby. As the results of above, the consciousness of flapper were rebellious attitude, liberalism and actualism. The designs of flapper fashion were expressed by simplicity, functionality, nudity and rhythm. The flapper images are as follows: First, they expressed modern image as a rebellious attitude. Second, flapper had a sensual image of freedom through rhythmical and speedy expression. Third, premature image for pursuing youth could be found. Therefore the changes of culture and women's life styles are very important points for fashion studies and the connecting fashion and other fields like novels is needed also for it.

  • PDF

Design and Control of a Six-degree of Freedom Autonomous Underwater Robot 'CHALAWAN'

  • Chatchanayuenyong, T.;Parnichkun, M.
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 2004년도 ICCAS
    • /
    • pp.1110-1115
    • /
    • 2004
  • Water covers two-thirds of the earth and has a great influence on the future existence of all human being. Thailand has extensive coastline and near shore water that contain vast biological and mineralogical resources. The rivers and canals can be found around the country especially in the Bangkok, which once called the Venice of the East. Autonomous underwater robot (AUR) will be soon a tool to help us better understand water resources and other environmental issues. This paper presents the design and basic control of a six-degree of freedom AUR "Chalawan", which was constructed to be used as a testbed for shallow. It is a simple low cost open-frame design, which can be modified easily to supports various research areas in the underwater environment. It was tested with a conventional proportional-integral-derivative (PID) controller. After fine-tuning of the controller gains, the results showed the controller's good performances. In the future, the dynamic model of the robot will be analyzed and identified. The advanced control algorithm will be implemented based on the obtained model.

  • PDF

유한요소해석에서 r-h형 적응법에 관한 연구 (A Study on the r-h methods in Finite Element Analysis)

  • 김동일;유형선
    • 전산구조공학
    • /
    • 제6권3호
    • /
    • pp.125-137
    • /
    • 1993
  • 최근 유한요소해석에서 보다 정확한 해를 위한 적응해석법에 대해 많은 연구가 이루어지고 있다. 본 논문은 요소 면적당의 오차를 균일화하여 절점을 최적의 위치로 변화시키는 r법과 오차가 큰 요소를 같은 모양의 요소로 세분시키는 h법을 혼합한 rh형 적응해석법을 사용하였다. 그 결과 같은 자유도에서 h법과 rh법의 오차감소율과 수렴속도는 거의 같에 나타났지만, rh법은 h법만 사용했을 때보다 전체 자유도 증가를 최대한 억제한 상태에서 정확한 유한요소해를 얻을 수 있었다.

  • PDF

$H_{\infty}$ 2 자유도 제어기를 이용한 CNC 시스템의 가공 정밀도 향상에 관한 연구 (A study on the improvement of cutting precision of CNC system using $H_{\infty}$ 2-degree-of-freedom controller)

  • 최성규;최병욱;현용탁;강성귀;권욱현
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
    • /
    • pp.1040-1043
    • /
    • 1996
  • The accuracy of the servo control in CNC system has a great influence on the duality of machine product. Tracking performance of the servo control is deteriorated mainly by the time delay of the servo system and the inertia of the work table or bed. Contouring errors occur in every interpolation steps by the effect of the tracking performance. In this paper, $H_{\infty}$ two-degree-of-freedom(TDF) controller is designed for improvement to improve the tracking performance. The designed controller is applied 3-axis machining center model and the cutting accuracy is simulated in case of corner cutting, circular and involute interpolation. Simulation results show that $H_{\infty}$ TDF controller designed in this paper has a good effect to improve tracking performance in CNC system.

  • PDF