• 제목/요약/키워드: physical length

검색결과 2,021건 처리시간 0.032초

유압실린더의 학습에 의한 위치제어 (Piston control of hydraulic cylinder using an learing strategy)

  • 박성환;권기수;허준영;이진걸
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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    • pp.1122-1126
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    • 1991
  • As microcomputers have become widespread and the high speed solenoid valves have been developed, digitally controlled hydraulic systems are used in many applications. This study deals with position control of hydraulic cylinder operated by two port 3-way high speed solenoid valve using a self-learning strategy. This was done by developing a control algorithm for the microcomputer which always automatically adjust the length of control pulse to the optimum value in accordance with the error regardless of changes in the operating condition and physical differences between components. Tests carried out in the laboratory indicate that a positional accuracy could be improved.

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폴리프로필렌 섬유용 알킬치환 초소수성 염료의 친화력 분석과 예측을 위한 Molecular Descriptor의 활용 (Application of Molecular Descriptor for Prediction and Analysis of the Affinity between Alkyl Substituted Super Hydrophobic Dyes and Polypropylene Fibers)

  • 장경진;정종석;김태경
    • 한국염색가공학회:학술대회논문집
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    • 한국염색가공학회 2008년도 제39차 학술발표회
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    • pp.77-78
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    • 2008
  • Affinity between alkyl substituted super hydrophobic dyes and polypropylene fiber has been analyzed by using the molecular descriptor as a method to predict chemical and physical characteristics of compounds. Hydrophobicity of synthesized dyes calculated by LogP which is one of molecular descriptors was increased continuously as the length of alkyl substituents increased.

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SURFACE BRIGHTNESS AND MASS DISTRIBUTION OF THE LATE TYPE SPIRAL GALAXY NGC 2403

  • Lee, Yoo-Mi;Chun, Mun-Suk
    • 천문학회지
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    • 제22권1호
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    • pp.31-41
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    • 1989
  • Luminosity profile of the late type spiral galaxy NGC 2403 was obtained using the PDS scan of the plate. Some physical parameters (scale length, total magnitude, central brightness, disk to bulge ratio and concentric indices) were calculated from the brightness distribution. Total mass and the mass to luminosity ratio were estimated from the fitting of various mass models.

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상관분석(相關分析)에 의(依)한 타월직물(織物)의 품질평가(品質評價) (A Study on Correlational Analysis of Towel Fabric Quality)

  • 박병기;임진모
    • 품질경영학회지
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    • 제7권2호
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    • pp.11-16
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    • 1979
  • Recently towel cloth has a good prospect as sports wear and out fashion wear. So we will discuss correlational effects between towel cloth quality and it's physical properties. In order to investigate the effect of pile length on the stiffness and absorption of the towel cloth, some experiments have been carried out, and then analyzed by the correlation coefficient.

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Optimal Design of Arrayed Waveguide Grating

  • Jung, Jae-Hoon
    • Journal of the Optical Society of Korea
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    • 제8권3호
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    • pp.99-103
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    • 2004
  • This paper describes the optimal design of an AWG spectrum to meet various specifications and improve some physical parameters. The objective function is the norm of the difference between design parameters and target values. To obtain the design parameters, the Fourier model is employed and the design variables arc spacing of array waveguide, width of array waveguide, optical path difference, and focal length. The (1+1) Evolution Strategy is employed as the optimization tool. The optimization procedure is applied to a 16-channel AWG and the optimized design variables will considerably improve the system performance.

손가락 비율과 체력과의 관계 분석 (Relational Analysis between Digit Length Ratio and Physical Fitness)

  • 최경호;유강원;유강수
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2012년도 춘계 종합학술대회 논문집
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    • pp.409-410
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    • 2012
  • 낮은 악력과 높은 악력으로 2등분 했을 때, 손가락 비율(2D:4D)에 대해 낮은 악력을 가진 남자가 높은 악력을 가진 남자보다 더 높은 2D:4D 비율을 가지고 있다. 이와 같은 이론을 토대로, 국내 대학생 중 축구선수를 대상으로 손가락 비율(2D:4D)과 체력과의 상관관계를 분석해보고자 한다.

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물리치료사의 요통 유병률과 관련요인 (Prevalence Rate of Low_Back Pain and Its Related Factors in Physical Therapists)

  • 정수연;신형수;박재용
    • The Journal of Korean Physical Therapy
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    • 제17권2호
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    • pp.22-37
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    • 2005
  • This study was performed to investigate LBP(low-back pain) prevalence rate and its related factors inphysical therapists. A self-administered questionnaire survey was conducted to 522 physical therapists in Daegu and Gyeongsangbuk. The LBP prevalence rate for recent 6 months was $61.7\%$. According to age, the prevalence rate was highest in the group aged 24 or less for both male and female physical therapistis. For male physical therapists , it was higher in smokers and drivers, but for female ones, it was not in a significant relationship with smoking and driving. According to work experience, the prevalence rates of those who had been working for less than one year were the highest, and those who had been working at hospitals and clinics were $69.1\%$, significantly high. According to therapy techinque, the prevalence rate related ti PNF was $71.6\%$, the highest and to occupational therapy was $34.3\%$, the lowest. According to working environment for six months, in both male and female physical therapists. LBP prevalence rate was in a statistically significant relationship with work hours during the day, night and weekend duties, repetitive works, motions that bend or twist the waist, the number of patients per day, the number of time to help patients per day, the number of time to carry medical equipment per day and the length of time to work standing. The rate was also higher when physical therapists fekt nire stress from their work. According to the result of multiple logistic regression analysis, male was in a significant relationship with work experience and motions that bend or twist the waist and female was in a significant relationship with work hours during the night and weekend duties, the number of time to help patients per day, motions that bena or twist the waist, actions taken to protect the waist. As for the developmental pattem of LBP in the group of physical therapists with LBP for six moths, $15.7\%$ of them had LBP for first time, $42.3\%$ had recurred LBP, and $42.0\%$ had chronic LBP. As for the causes of LBP, $51.7\%$ said that it was because they worked in the same posture for a long time, and as for how to treat LBP, 48.8% said that they treated themselvs or got help from their co-wokers. The results presented above suggest that physical therapists are exposed to high risk of LBP caused form occupational activities. Therefire, it is necessary to improve working environment to reduce the occurrence of LBP and to develop education programs for preventing the occurrence and recurrence of LBP.

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뇌졸중 환자의 보행시간에 대한 현 신호체계 분석 (Analysis of Current Traffic Signals for Pedestrians according to the Walking Times of Stroke Patients)

  • 이동진;나은예;박선미;박세진;박엘림;박완서;배우리;백화신;서경태;서동현;안승우
    • 대한임상전기생리학회지
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    • 제10권2호
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    • pp.7-14
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    • 2012
  • Purpose : This study investigated the validity of crosswalk signal time length with regards to elderly stroke patients. Methods : We recruited 60 elderly adults sixty years of age or older for our study. The participants were divided into three groups.Group A consisted of 20 healthy participants with no walking aids. Group B consisted of 20 stroke patients with no walking aids. Group C consisted of 20 stroke patients using a cane as a walking aid. We measured the walking times of participants for 7 m, 14 m and 21 m lengths. Results : Using an independent t test, there was a statistically significant difference in the walking times between Group A and Group B for all lengths. There was a statistically significant difference in the walking times between Group A and Group C for all lengths. There was no statistically significant difference in the walking times between Group B and Group C. There was a statistically significant difference between the three group when using ANOVA. Conclusion : From the results of this study, we infer that the signal times at crosswalks are inappropriate for elderly stroke participants who use a cane as a walking aid. Therefore further research should be conducted to determine the appropriate amount of additional time needed for the elderly to safely cross the street.

중년여성의 12주간 아헹가 요가 수련이 하체 불균형에 미치는 영향 (Effects of Iyengar Yoga Practice for 12 weeks on Lower Body Imbalance in Middle-aged Women)

  • 박윤하;김동희
    • 한국산학기술학회논문지
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    • 제18권1호
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    • pp.431-440
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    • 2017
  • 본 연구는 아헹가 요가 프로그램이 중년여성의 하체불균형에 미치는 영향을 분석하는데 그 목적이 있다. 연구의 대상자는 35-60세 사이의 중년여성으로서 요가 수련의 경험이 없으며 다른 운동 훈련에 참가 하지 않고, X-RAY검사와 간스테드 테크닉(Gonsted Technique) 분석을 통하여 골반불균형이면서 하지 길이의 차이가 있는 중년여성 24명을 선정하여 12주 동안, 주3회, 1일 90분 동안 수련하였다. 통계방법은 대응 t-검정을 실시하여 수련 전과 후를 비교하였고, 유의 수준은 0.05로 설정하였다. 이 연구의 결과는 첫째, 아헹가 요가는 골반 불균형을 교정하는데 통계적으로 유의한 결과를 나타냈다. 즉 골반 불균형 개선에서 좌 우 엉덩뼈 높이(p < 0.001), 좌 우 엉덩뼈 넓이 (p < 0.001), 좌 우 엉덩뼈 길이 ((p < 0.001), 좌 우 엉치뼈넓이 (p < 0.001)에서 수련 전보다 수련 후 그 차이가 감소하는 유의한 변화를 보여주었다. 둘째, 하지 길이의 변화에서는 아헹가 요가 수련 전 보다 수련 후에 좌 우 하지 길이 차이 (p < 0.001)가 현저하게 감소하였으며 통계적으로 유의한 효과를 나타내었다. 이상의 연구 결과에서 아헹가 요가 수련이 중년여성의 신체불균형을 교정하는데 매우 효과가 크다는 것을 알 수 있었다.

인덱스 보간법에 기반한 효율적인 서브시퀀스 매칭 기법 (An Efficient Subsequence Matching Method Based on Index Interpolation)

  • 노웅기;김상욱
    • 정보처리학회논문지D
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    • 제12D권3호
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    • pp.345-354
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    • 2005
  • 서브시퀀스 매칭은 데이터 마이닝 분야에서 중요한 연산 중의 하나이다. 기존의 서브시퀀스 매칭 알고리즘들은 하나의 인덱스만을 사용하여 검색을 수행하며, 인덱스를 생성하기 위하여 데이터 시퀀스로부터 추출한 윈도우의 크기와 질의 시퀀스의 길이 간의 차이가 커질수록 검색 성능이 급격히 저하된다. 본 논문에서는 이러한 문제점을 해결하기 위하여 인덱스 보간법에 기반한 새로운 서브시퀀스 매칭 기법을 제안한다. 인덱스 보간법이란 하나 이상의 인덱스를 구축하고 주어진 질의 시퀀스의 길이에 따라 적절한 인덱스를 선택하여 검색을 수행하는 기법이다. 본 논문에서는 먼저 사전 실험을 통하여 서브시퀀스 매칭을 수행하는 데에 있어 질의 시퀀스 길이와 윈도우 크기 간의 차이로 인한 성능의 변화를 관찰하고, 이 관찰을 통하여 물리적 데이터베이스 설계 관점에서 질의 시퀀스의 길이 분포에 따른 검색 비용 공식을 산출한다. 다음에, 윈도우 크기 효과에 의한 성능 저하를 개선하기 위해 인덱스 보간법에 기반한 새로운 검색 기법을 제안한다. 또한, 검색 비용 공식에 기반하여 제안된 검색 기법의 성능을 최적화할 수 있도록 다수의 인덱스를 구성하는 알고리즘을 제시한다. 마지막으로, 실제 데이터와 합성 데이터를 이용한 여러 가지 실험을 통하여 제안된 기법의 우수성을 검증한다.